US3831550A - Sonic wave generation - Google Patents

Abstract

In a first embodiment, a source of fluid under pressure is supplied to a conduit that is terminated by a transverse resonant cavity preferably having a square cross section. The cross section of the conduit and the cavity are dimensionally related. In a second embodiment, a shock wave generator is coupled to a transverse resonant cavity. The component wavelengths of the shock waves and the cross-section of the cavity are dimensionally related. A third embodiment combines the first and second embodiments. The primary resonant cavity itself may be supplemented by auxiliary resonant cavities that communicate with a partially enclosed area into which the primary resonant cavity opens. One or more of the auxiliary cavities may be fed in parallel with the primary cavity by auxiliary conduits. Further, an auxiliary cavity may be arranged in series with the primary cavity to form a fluidic reflecting surface at the back of the primary cavity. Fluid may be supplied to a transverse resonant cavity by two or more feed conduits. The cavity may form a network of closed interconnected geometric channels such as circles, squares, and triangles, that are either arranged in a single plane or in stacked planes.

Description

United 1 States Patent 1191 1111 3,831,550 Hughes Aug. 27, 1974 SONIC WAVE GENERATION 3,581,992 6/1971 Hughes 239/102 3,600,612 8 l97l Be it ll [75] lnvemorl Natm'e'HPgheS1 Ronmg H1115 3,613,452 10/1971 26211: Estates, Calif. [73] Assignee: Energy Sciences Incorporated, El Primary E aminep-Louis J. Capozi Segundo, Calif. Attorney, Agent, or Firm-Christie, Parker & Hale [22] Filed: Oct. 14, 1971 211 App]. No.2 189,206 [57] ABSTRACT Related Application Data In a first embodiment, a source of fluid under pressure [63] C t f S N 85 911 2 is supplied to a conduit that is terminated by a transommua lon'm'par 9 verse resonant cavity preferably having a square cross 1970, abandoned, which is a continuation-impart of Sen 827,451 April 23, 1969, section. 'I 'he cross section of the condult and the cav- 3,554,443, and a continuation-in-part of Ser. No. Y are dimensionally relateda second embed! 32,771, O 21, 1970, abandoned, and a ment, a shock wave generator is coupled to a transcontinuation-in-partof Ser. No. 158,915, July 1, verse resonant cavity. The component wavelengths of 1971, Pat. No. 3,730,160. the shock waves and the cross-section of the cavity are dimensionally related. A third embodiment combines [52] US. Cl. 116/137 A, 239/102 th fir t and second embodiments. The primary reso- [51] Int. Cl. B06b 3/00 nant cavity itself may be supplemented by auxiliary Field of Search-m 357 resonant cavities that communicate with a partially 1 16/65, 67, 70, 11 3 137 191 enclosed area into which the primary resonant cavity 235/201; 239/4, opens. One or more of the auxiliary cavities may be 15 fed in parallel with the primary cavity by auxiliary conduits. Further, an auxiliary cavity may be arranged [56] References Cited in series with the primary cavity to form a fluidic re- UNITED STATES PATENTS fleeting surface at the back of the primary cavity. 2 019 596 11/1935 Broden 116/137 R Fluid may be Supplied to a transverse resonant cavity 2:364:987 12 1944 T66 261/78 y two or more feed Conduits The Cavity y form 3 2,755,767 7/1956 Lavavasseur 116/137 A network f los d inter nnected geometric channels 3,230,923 1/ 1966 Hughes 116/137 A such as circles, squares, and triangles, that are either 3,3 8,5 7 I 8 O ap arranged in a single plane or in stacked planes. 3,432,804 3/1969 Beeken 3,554,443 1/1971 Hughes 116/137 A x 56 Clains, 15 Drawing Figures 115+ V 53 43 ig .I

Z A? 4 3:1: i 5/ T I if 54 4 600/265 07 500965 FLU/D 04/052 Hum UMDEQ PATENTED AUBZ 74 SIIUQUB 50026; 0/: FLU/D UNDER PATENTEDwszmm aim 30s a CROSS-REFERENCE TO RELATED APPLICATIONS This application claims under 35 USC 120 the benefit of the filing dates of the following applications: Specifically, the instant application is a continuation-inpart of application Ser. No. 85,911 filed Nov. 2, 1970 now abandoned, which is a continuation-in-part of application Ser. No. 827,451 filed Apr. 23, 1969 now US. Pat. No. 3,554,443. Also the instant application is a continuation-in-part of application Ser. No. 82,771 filed Oct. 21, 1970, now abandoned and a continuation-in-part of application Ser. No. 158,915 filed July 1, 1971 now US. Pat. No. 3,730,160.

BACKGROUND OF THE INVENTION This invention relates to the generation of coherent pressure wave energy having high energizing capability and, more particularly, to highly efficient and long range wave generators employing resonant action.

Whistletype sonic wave generators, such as the Hartmann generator, have been known for a number of years. This type of sonic wave generator typically employs a nozzle and a cylindrical resonant cavity aligned with the nozzle on a common longitudinal axis in spaced proximity to the nozzle outlet. At one end, the cylindrical resonant cavity is open to communicate with the nozzle outlet and at the other end the cavity is closed. The nozzle is dimensioned to convert a subsonic flow of gas applied to the nozzle at a particular pressure into sonic flow, thereby producing shock wave pressure pulses. The shock wave pressure pulses emanating from the nozzle outlet are coupled to the resonant cavity, where these pulses are transformed into sonic wave energy by resonant action. The resonant condition is dependent upon the maintenance ofa critical distance from the nozzle outlet plane to the closed end of the cavity in terms of the wavelength of the shock wave pulses. Reference is made to my US. Pat. No. 3,230,923, which issued Jan. 25, 1966, for a typical prior art whistle-type sonic wave generator.

Compared with other types of sonic wave generators, such as electromechanical devices, a whistle-type sonic wave generator has a number of advantages including the simplicity of design and the characteristics of the sonic waves it emits. Unfortunately, the presently known configurations of whistle-type sonic wave generators are too inefficient to make their use practical for many industrial applications. For one thing, the fluid must be supplied to the nozzle under a very high pressure in order to produce a usable sonic wave energy level. Further, if the pressure conditions change, the dimensions of the nozzle are not appropriate for peak efficiency of shock wave generation and the wavelength of the shock wave pulses shifts so the resonant cavity becomes detuned, because the critical distance changes. In addition, the proximity required between nozzle and cavity results in a bulky piece of equipment that may prove difficult to place near the action zone to be energized. As a result of these considerations, the full potential of whistle-type sonic wave generators has not been full exploited to date.

Among the various industrial applications of a whistle-type sonic wave generator is the atomization of a fluid into a finely suspended state. For example, my copending application Ser. No. 158,915, filed July 1, 1971, and entitled ENERGIZATION OF THE COM BUSTIBLE MIXTURE IN AN INTERNAL COMBUS- TION ENGINE, discloses a number of the devices disclosed and claimed herein in connection with an internal combustion engine. The combustible mixture is energized prior to combustion in a manner that achieves a substantial reduction of engine pollutants, improved performance, and reduced fuel consumption.

SUMMARY OF THE INVENTION The invention involves a resonant cavity in a whistle type sonic wave generator that is totally new in its configuration and effect. The resonant cavity is excited by pressure pulses having a wavelength or component wavelengths that are dimensionally related to the cross section of the cavity. The resonant cavity extends along a longitudinal axis that is generally transverse to the direction of propagation of the pressure pulses at the point where they are coupled to the cavity, and has one or more exits for the emission of sonic wave energy. Preferably, the cavity has a square cross section with a side dimension that is a multiple of the wavelength of the pulsations. The sonic wave energy generated in the resonant cavity has amazing characteristics, vis-a-vis, sonic wave generators in the prior art. The propagating range and energizing capability of the sonic waves far exceed expectations based on experience with whistletype devices. The energizing capability is so extreme that the molecules of the fluid in which the sonic waves are formed may be ionized. For example, the nitrogen molecules of air may become ionized when subjected to this energization. Thus, the invention can be used to transmit sonic wave energy relatively long distances and to energize to a high level a fluid medium into which the sonic wave energy is released.

In a first embodiment, a fluid source isconnected to the resonant cavity by a conduit that extends transverse to the cavity. A linear cross-sectional dimension of the conduit and a linear cross-sectional dimension of the cavity are related. As the fluid traverses the conduit, even at subsonic velocity, there develop pressure pulses that are converted to the sonic wave energy in the cavity by resonant action.

In a second embodiment, a shock wave generator is coupled to a transverse resonant cavity. The shock wave generator could comprise a supersonic converging-diverging nozzle or a conduit supplied by a fluid under sufficient pressure to produce sonic flow. An important advantage of the invention is the fact that the shock wave pressure pulses can be transmitted long distances without substantial attenuation when a shock wave generating cell of the type disclosed in my US. Pat. No. 3,554,443 is coupled to the resonant cavity by a conduit having a linear cross-sectional dimension that is related to the wavelength of the shock wave pressure pulses. This permits the shock wave generator and the supply of fluid to be remotely placed from the region where the sonic wave energy is to be utilized to a more convenient location; in other words, it permits physical separation of pressure pulse generation and resonant action.

A third embodiment combines the first and second embodiments. A conduit connects a fluid source to a transverse resonant cavity, and a shock wave generator is also coupled to the cavity. The wavelength of the shock wave pulses, the linear cross-sectional dimension intensity and large wavelengths related to that of the shock waves. The shock wave pulses serve to trigger oscillation of the pressure pulses from the conduit to energize highly the entire fluid stream.

The primary resonant cavity can be supplemented by auxiliary resonant cavities spaced at equal intervals around an enclosure into which the primary resonant cavity opens to enhance the energizing capability of the sonic wave energy. The auxiliary cavities, which communicate with the enclosure, have a hexahedral, preferably cubical, shape with linear side dimensions that are related to the wavelength of the pressure pulses. Pressure pulses can also be coupled directly to one or more of the auxiliary cavities so these auxiliary cavities are in effect connected in parallel with the primary cavity. Further, an auxiliary cavity can be connected in series with the primary cavity to further enhance the energizing capability of the sonic wave energy generated. This, in effect, provides a fluidic reflecting surface at the back of the primary cavity when the series connection to the auxiliary cavity is a multiple ofthe pressure pulse wavelength.

A particularly effective sonic wave generator is formed when fluid is supplied to the resonant cavity by two or more feed conduits, between which an exit from the cavity is formed. The distance from each conduit to the exit is preferably a multiple of the linear crosssectional dimension of the cavity. This principle can be employed to form a resonant cavity that is a network of closed, interconnected, geometric channels, such as circles, squares, and triangles, arranged either in a single plane or in stacked planes. In applying this principle to a network of closed channels, each channel may be viewed as a separate resonant cavity, and the interconnections between channels may be viewed as the feed conduits and the exits. It has been found that the advantageous characteristics, i.e., propagating range and energizing capability, are enhanced as the network is expanded in complexity.

It has been found that a very effective cross-sectional side dimension for a resonant cavity having a square cross section is a dimension in the range of 0.170 to 0.195 inches, 21 multiple and/or submultiple thereof. The resulting sonic wave energy, which has a wavelength or component wavelengths corresponding to this side dimension, exhibits exceptionally long propagating range and high energizing capability in a gaseous medium.

DESCRIPTION OF THE DRAWINGS The features of specific embodiments of the best mode contemplated of carrying out the invention are illustrated in the drawings, in which:

FIG. 1 is a schematic block diagram of one embodiment of the invention;

FIG. 2 is a schematic block. diagram of another embodiment of the invention;

FIG. 3 is a schematic block diagram of a further embodiment of the invention, which combines the embodiments of FIGS. 1 and 2;

FIGS. 4A and 4B are front and top sectional views, respectively, of the embodiment of FIG. 1 arranged with a plate, a cavity, and a conduit;

FIG. 5 is a perspective sectional view of the embodiment of FIG. 3 taken through the same plane of a plate as FIG. 4B and arranged with a number of auxiliary resonant cavities in addition to a primary cavity;

FIG. 7 is a perspective sectional view of the embodiment of FIG. 2 taken through the same plane of a plate as FIG. 4B and arranged with a number of auxiliary resonant cavities in addition to a primary cavity and a number of auxiliary conduits arranged in parallel with a primary conduit;

FIG. 8 is a perspective sectional view of the embodiment of FIG. 1 taken through the same plane of a plate as FIG. 4B and arranged with a resonant cavity having an exit between two feed conduits;

FIGS. 9A and 9B are front and side sectional views, respectively, of the embodiment of FIG. 1 in which a resonant cavity is formed by two closed interconnected geometric channels in the same plane;

FIG. 10 is a side sectional view of a modified version of the arrangement of FIGS. 9A and 9B;

FIGS. 11A and 11B are a disassembled front elevation view and an assembled side elevation view, respectively, of another arrangement of the embodiment of FIG. 3 in which the resonant cavity is formed by closed interconnected geometric channels in stacked planes; and

FIG. 12 is a perspective sectional view of another arrangement of the embodiment of FIG. 2, taken through the same plane of the plate as FIG. 4B, and arranged with a resonant cavity formed by a closed geometric network.

DETAILED DESCRIPTION OF THE SPECIFIC EMBODIMENTS As used in this specification, the term pressure pulses means periodic positive pressure pulses that are predominately unipolar, i.e., the pressure at a given point in space pulsates between ambient pressure and a pressure higher than ambient pressure, so compression of the fluid molecules repeatedly occurs, although between the compressive pulses slight negative pulses may occur. Coherent pressure pulse energy consists of pressure pulses having the same wavelength or a number of component wavelengths that are multiples or submultiples of each other, i.e., that are multiply related. Shock waves are pressure pulses produced as a result of supersonic fluid flow. The term sonic waves means periodic bipolar pressure waves, i.e., the pressure at a given point in space sinusoidally oscillates between a pressure higher than ambient and a pressure lower than ambient, so compression and rariflcation of the fluid molecules alternately occur. Coherent sonic wave energy consists of sonic waves having the same wavelength or a number of component wavelengths that are multiply related. The term pressure waves" is generic to pressure pulses and sonic waves. The term coherency as used herein does not exclude the presence of some pressure wave energy at component wavelengths that are not multiply related to the remaining component wavelengths or to the presence of some random pressure wave energy, analogous to background noise; rather the term coherent" is used to designate that a substantial amount of pressure wave energy at multiply related wavelengths is present.

The invention is concerned with generating pressure pulses and resonating the generated pressure pulses to produce sonic waves that exhibit a long propagating range and a high energizing capability. Pressure pulses are coupled to a resonant cavity that extends along a longitudinal axis generally transverse to the direction of propagation of the pressure pulses at the point where they are coupled to the cavity. The wavelength or component wavelengths of the pressure pulses and the cross section of the resonant cavity are matched in that they are dimensionally related. The relationship among the significant dimensions of the resonant cavity and the wavelength or component wavelengths of the pressure pulses are extensively illustrated in the embodiments and arrangements disclosed below.

It has been found that sonic waves produced in accordance with the principles of this invention have a surprisingly long propagating range, i.e., they travel far without significant attenuation, and exhibit an extraordinarily high energizing capability. To date, the energizing capability of the various embodiments and ar rangements disclosed herein has been measured in terms of the resulting improvement in a combustion process, such as the reduction in emissions (hydrocarbons, carbon monoxide, and the oxides of nitrogen) and the increase in the efficiency of an internal combustion engine. However, the energizing capability of the invention can be utilized to great advantage in many other fields, including gas burners and heaters, surface cleaning, and chemical mixing of fluids or powders.

It is felt that the extraordinary properties of the sonic waves produced according to the invention are in large measure attributable to the highly ordered spatial nature of the sonic waves and pressure pulses, i.e., to their coherency. The intense energization that results appears to have a tendency to ionize a gaseous medium and to produce electromagnetic-like waves. Electromagnetic phenomena may be associated with coherent pressure wave energy in the following way: electromagnetic waves generated while the fluid is being processed in accordance with the invention align the fluid molecules spatially to produce a resulting disturbance in the form of pressure waves; as the electromagnetic waves propagate they continue to align and reinforce the resulting disturbance, i.e., the pressure waves; thus, the pressure waves are intensified by the electromagnetic waves and are renewed as they propagate. Support for this theory is found in the fact that the ratio of the speed of light to the speed of sound in airat standard conditions is equal to 0.087 X Two times 0.087 inches, actually a range of 0.l70 to 0.195 inches, has been found to be the basic dimension for most effectively practicing the invention. The actual dimension within the range of 0. l 70 to 0. 195 inches that is preferable depends upon the pressure drop, the higher the pressure drop the higher the basic dimension within the range.

The reinforcement of the pressure waves may also be by electromagnetically related waves at the speed of sound or at a somewhat greater speed than that of sound. The text, Electrodynamics of Particles and Plasmas, P. C. Clemmow and J. P. Dougherty, Addison-Wesley Publishing Co., 1969, which is incorporated herein by reference, describes electromagnetically related waves that are closely related to the speed of sound, and it points out how energy may be coupled air is channeled through the cell disclosed in my U.S.

Pat. No. 3,554,443, it becomes substantially more highly ionized. The amplification of the ionization has been measured and confirmed by the increased effectiveness of the ionized air to clean charged particles from insulative surfaces.

The ionization is felt to be attributable to two characteristics of the invention: the interaction of the multiply related frequency components of pressure waves such as those produced, for example, in the shock wave generating cell of my US. Pat. No. 3,554,443, and the effectiveness of the resonant action such as that taking place, for example, in the network of channels having a square cross section of FIG. 8 herein. The ionized gases thought to be produced by the invention would have many uses. Among these are surface cleaning and combustion. ln internal combustion, for example, the nitrogen of the fuel-air mixture may be ionized to the point that it chemically inhibits the formation of oxides of nitrogen during combustion. This inhibition is explainable in one of two ways:

l. The nitrogen is rendered chemically inert by applying sufficient ionizing energy to the nitrogen atoms to remove the five electrons from their outer shell, leaving only the two electrons of their inner shell. Such atoms, being devoid of electrons in their outer shell, do not tend to combine with other atoms, and, hence, do not form oxides of nitrogen.

2. The nitrogen is ionized, and the nitrogen atoms ac quire an electrical charge that repells the ionized atoms of oxygen and/or fuel. This causes the oxygen to combine with the fuel rather than with the nitrogen.

It has been found that the reduction in the oxides of nitrogen produced during internal combustion is generally proportional tothe amount of pressure wave energy introduced by the devices of the invention. This would indicate that the amount of pressure wave energy determines the extent of nitrogen ionization, which, in turn, determines the extent of inhibition of formation of oxides of nitrogen.

it is believed that nitrogen ionization brought about by the devices of the invention is greatly multiplied and intensified after the onset of combustion in the cylinder of an internal combustion engine. This intensification, which would account for the marked drop in the oxides of nitrogen, is believed to be one example of an important characteristic of the invention, namely, that raising the internal energy of a fluid either before or after the fluid is processed by a device of the invention greatly intensifies, i.e., amplifies, the energization of such fluid. The internal energy of a fluid can be raised thermally. by heating or electrically by ionizing. Other ex amples would be to heat the fluid prior to passing it through a device of the invention or to subject the fluid to an ionizing electrostatic field after passing it through a device of the invention.

It is further believed that the extent of multiplication and intensification of the nitrogen ionization that takes place after the onset of combustion in the cylinder of an internal combustion engine is directly related to the flame temperature in the cylinder in other words,

the higher the flame temperature, the higher the internal energy, and the higher the internal energy, the more amplification of the ionization. Experimental verification of this is found in the fact that the closer the operation of an internal combustion engine energized by the devices of the invention is to stoichiometric combustion, as measured by the carbon dioxide production, the greater is the reduction in the oxides of nitrogen. In contrast, the oxides of nitrogen produced in an internal combustion engine not energized by the devices of the invention are a maximum near the stoichiometric point, due to the maximum flame temperature.

Therefore, when an internal combustion engine is energized by the devices of the invention, it is preferable to adjust the fuel-air mixture for stoichiometric combustion. This minimizes the production of the oxides of nitrogen.

Although the pressure pulses resonated in accordance with the invention can be generated by any known type of sonic or supersonic flow nozzle, it is preferable to employ the shock wave generating cell disclosed in my U.S. Pat. No. 3,554,443, which issued on Jan. 12, 1971. The disclosures of my U.S. Pat. No. 3,554,443 and my U.S. Pat. No. 3,531,048, which issued Sept. 29, 1970, are incorporated herein by reference. In this shock wave generating cell, a convergingdiverging supersonic flow nozzle is formed in a cylindrical passage by fluid boundary layers that adjust the effective nozzle dimensions to compensate for pressure changes. The boundary layers are developed by a number of holes leading into the cylindrical passage. As described in my U.S. Pat. No. 3,554,443, the hole diameters and the dimensions of the cell are selected so the component wavelengths generated in the cell are multiples and submultiples of each other. As a result, the cell radiates coherent pressure pulse energy. For the dimensions stated in my U.S. Pat. No. 3,554,443, the component wavelengths are multiples or submultiples of a basic wavelength in a range of 0.170 to 0.195 inches, depending on the inlet in a range of 1 to 20 psig. For the purpose of discussion, a nominal value of 0.180 inches will be presumed for the basic wavelength of the cell in the exemplary dimensions given in the following embodiments and arrangements.

In FIG. 1, a source 10 of fluid under pressure, which could be air at a gauge pressure in the range of 0.1 to 14 psi, is connected to one end of a feed conduit 11. The other end of conduit 11 is connected to a resonant cavity 12 that extends along an axis transverse to the axis of conduit 11 at the point of connection and preferably has a rectangular or square cross section. Cavity 12 has an exit communicating with the atmosphere. Pursuant to the present invention, it has been discovered that, even though the fluid flowing in laminar fashion through conduit ll due to the pressure drop between source 10 and the exit of cavity 12 is traveling at subsonic speed, there are generated in conduit 11 pressure pulses related in wavelength to the linear cross-sectional dimensions of conduit 11 and the velocity of the fluid passing therethrough. The linear crosssectional dimensions of conduit 11 are selected'so the wavelength of its pressure pulses are dimensionally related to a linear crosssectional dimension of cavity 12. As a result, these pressure pulses resonate in cavity 12,

are converted by resonant action to sonic wave energy,

of usable intensity, and pass into the atmosphere through the exit of cavity 12. However, since the wavelength of the pressure pulses is also in part determined by the velocity of the fluid, the pressure pulses move in and out of resonance with cavity 12 as the pressure of source 10 varies. Accordingly, the intensity of the sonic wave energy emitted by cavity 12 fluctuates as the pressure of source 10 varies. For some pressure ranges it is preferable for conduit 11 to have a linear crosssectional dimension equal or multiply related to a linear cross-sectional dimension of cavity 12.

In summary, for controlled conditions of fluid pressure, the embodiment of FIG. 1 is an effective sonic wave generator that produces sonic wave energy without requiring the introduction of supersonic or sonic fluid flow. The energizing capability of this'sonic wave generator is limited by the dependence of the wavelength of the resulting sonic wave energy upon the lin ear cross-sectional dimensions of conduit 11; in order to reduce the wavelength of the sonic wave energy for the purpose of increasing its energizing capability, the linear cross-sectional dimensions of conduit 11 must be reduced, thereby restricting the flow rate of the fluid being processed.

It is a well known phenomenon that when the ratio of inlet pressure to outlet pressure across an orifice exceeds a critical pressure ratio, 1.9 in the case of air, fluid will flow through the orifice at sonic speed, thereby producing shock wave pressure pulses having a wavelength related to the linear cross-sectional dimensions of the orifice. Thus, source 10 and conduit 11 of FIG. 1 comprise a shock wave generator if the air pressure of source 10 is raised above 1.9 atmospheres.

In FIG. 2, a shock wave generator 13 is connected by a coupling 14 to a transverse, preferably rectangular resonant cavity 15, which could be identical to cavity 12 of FIG. 1. Shock wave generator 13 could comprise source 10 and conduit 11 of FIG. 1 if the air of source 10 is under more than 1.9 atmospheres, or could comprise the shock wave generating cell described in my U.S. Pat. No. 3,554,443. Shock wave generator 13 produces periodic shock wave pressure pulses having a wavelength or component wavelengths related to a linear cross-sectional dimension of cavity 15. Coupling 14 is preferably a conduit having a cross-sectional dimensional relationship to cavity 15. It has been discovered that the use of such a conduit provides very efficient coupling from shock wave generator 13 to resonant cavity 15 without substantial attenuation, even when the shock wave generator and resonant cavity are physically separated by a large distance, e.g., as large as 20 feet or more. However, coupling 14 could also take other forms, such as free space propagation, albeit at the cost of greater attentuation to the shock wave pressure pulses produced by generator 13. In either case, the shock wave pressure pulses coupled to cavity 15 are transformed by resonant action into sonic wave energy possessing much higher energizing capability than the subsonically produced pressure pulses that excite cavity 12.

In FIG. 3, the embodiments of FIGS. 1 and 2 are combined to provide a sonic wave generator capable of producing even more highly energized coherent sonic wave energy. A source 16 of fluid under pressure, which corresponds to source 10 of FIG. 1, is connected to one end of a feed conduit 17, which corresponds to conduit 11 of FIG. 1. The other end of conduit 17 is connected to a transverse rectangular resonant cavity 18, which corresponds to resonant cavity 12'of FIG. 1

rather large value is selected in order to provide a large rate of fluid flow. As indicated above, this results in pressure pulses having a rather large wavelength. On the other hand, shock wave generator 19 is designed to produce pressure pulses with a rather small wavelength. The large and small wavelengths are both dimensionally related. When the large wavelength energy produced by conduit 17 and small wavelength energy produced by shock wave generator 19 combine in cavity 18, in addition to the resonant process, it is believed an energy mixing process takes place which is analogous to the heterodyne mixing process of electromagnetic radio waves. It is believed this mixing action increases the intensity of the coherent sonic wave energy produced, vis-a-vis the embodiment of FIG. 2, and decreases the wavelength of the predominent energy component wavelengths of the coherent sonic waves produced, vis-a-vis the embodiment of FIG. 1. At any rate, a fluid flowing at a high flow rate is energized more by this embodiment than by either of the embodiments of FIGS. 1 and 2, i.e., this embodiment processes the fluid more completely.

In FIGS. 4A and 48, a feed conduit 31 corresponding to conduit 11 of FIG. I, or coupling 14 of FIG. 2, and a resonant cavity 32 corresponding to cavity 12 of FIG. I, or cavity 15 in FIG. 2, are formed in a metallic plate 30. Conduit 31 has a circular cross section, as represented in FIG. 4A, and is of arbitrary length, as represented in FIG. 4B. A source of fluid under pressure or a shock wave generator (not shown) would be connected to the end of conduit 31, not represented in FIG. 48. For the purpose of discussion, it is assumed the shock wave generating cell of my US. Pat. No. 3,554,443 is used. The other end of conduit 31 communicates with resonant cavity 32, which preferably has a square cross section with a width X and a height Z (e.g., X, Z =0. 180 inches). The cross-sectional diameter D of conduit 31 is dimensionally related to the width X and the height Z (e.g., D =0.l80 inches). The ends of resonant cavity 32, which are open, comprise exits that communicate with holes 33 and 34 formed in plate 30. An intersection is formed where conduit 31 is connected to cavity 32. As shown, the longitudinal axis of cavity 32 is transverse to the longitudinal axis of conduit 31 at the intersection, so pressure pulses are coupled to cavity 32 in a direction transverse to its longitudinal axis. It is believed sonic wave energy is pro duced in resonant cavity 32 by resonant action in two mutually perpendicular dimensions, i.e., between the two pairs of parallel sides of cavity 32, and continues as the energy propagates along the longitudinal axis of cavity 32 to its open ends where the sonic wave energy is emitted in the direction of the plane of plate 30 into the space enclosed by holes 33 and 34 to form therein standing sonic waves. The sonic wave energy then propagates outwardly in a direction transverse to the plane of plate 30. The cross-sectional dimensions X, Z, and D are significant. The length of cavity 32, Le, the distance between holes 33 and 34, and the length of conduit 31 are not significant.

In FIG. 5, there is shown a modified version of plate 30, designated 30. A feed conduit 35 having a square cross section is formed in plate 30'. At one end, conduit 35 communicates with a transverse resonant cavity 36 having a square cross section. The ends of cavity 36 are open to communicate with holes 37 and 38 formed in plate 30'. The cross-sectional side dimension of conduit 35 are equal to the cross-sectional side dimension of resonant cavity 36. It is to be noted that resonant cavity 36 is shorter in length in the modification of FIG. 5 than in FIGS. 4A and 48 because openings 37 and 38 are closer together.

In FIG. 6, conduit 17, shock wave generator 19, coupling 20, and resonant cavity 18 of FIG. 3 are shown in detail. Conduit 17 comprises an external pipe 40, a coupling 41, and an elongated passage 42 all having circular inside cross-sections with equal diameters. Pipe 40 is connected by coupling 41 to elongated passage 42, which extends through a metallic plate 43. Plate 43 has holes 55 and 56 through it. Shock wave generator 19 comprises a shock wave generating unit 39 having an inlet to which a source 44 of fluid under pressure is applied. For the purpose of discussion, it is assumed that source 44 and source 16 are both air at a pressure of more than one atmosphere, and the space enclosed by holes 55 and 56 is at atmospheric pressure. Conversely, sources 16 and 44 could be air at atmospheric pressure, if a subatmospheric pressure were developed downstream, as would be the case in the intake system of an internal combustion engine. Preferably, unit 39 comprises a pair of shock wave generating cells arranged in tandem with each other as disclosed in my copending application Ser. No. 13,977, filed Feb. 25, 1970, now abandoned. For the purpose of discussion, it is assumed that the individual cells of unit 39 each have the dimensions and hole diameters specified in my US. Pat. No. 3,554,443. In such case, the subsonic air stream drawn into unit 39 is converted therein to a supersonic air stream that produces shock wave pressure pulses having a basic wavelength of 0.180 inches. A tube 45 connects the outlet of unit 39 to passage 42 at a point intermediate its ends.Thus, coupling 20 comprises tube 45 and a portion of passage 42. Tube 45 has a circular cross section equal in diameter to passage 42 (e.g., 0.180 inches).

There are formed in plate 43 a primary resonant cavity 46 and auxiliary resonant cavities 47, 48, 49, 50, 51, 52, and 53. Primary cavity 46 is coupled to auxiliary cavity 53 by a slot 54. One end of primary cavity 46 and auxiliary cavity 53, and auxiliary cavities 47, 48, and 49 are distributed at 90 intervals about the periphery of hole 55. Similarly, the other end of primary cavity 46 and auxiliary cavity 53, and auxiliary cavities 50, 51, and 52 are distributed at 90 intervals about the periphery of hole 56. Primary cavity 46, auxiliary cavity 53, and slot 54 all have an identical height Z (e.g., Z, 0.180 inches). Primary cavity 46 has a depth X (e.g., X 0.180 inches) and a non-significant length that extends completely across the space between holes 55 and 56. Slot 54 has a width Y and a depth X (Y X 0.090 inches). Auxiliary cavity .53 has a depth X (e.g., X 0.090 inches) and a non-significant length that extends completely across the space between holes 55 and 56. Auxiliary cavities 47, 48, 49, 50, 51, and 52 all preferably have identical dimensions, namely, a height 2,, a width Y and a depth X (e.g., Z.,, Y.,, X, 0.180 inches). The dimensions X Z X Y X X Y and Z and the diameter of passage 42 are all significant. For ease of fabrication, the back wall of cavities 47 through 52 (i.e., the wall opposite the open side of the cavities) could be rounded somewhat. Thus, these cavities may be formed by machining. Instead of being cubical, these auxiliary cavities could be noncubical hexahedral. In summary, all the dimensions of the resonant cavities and conduits leading thereto are matched, so to speak, to the wavelength of the pressure pulses. As described in my US. Pat. No. 3,531,048, the cells comprising unit 39 are self-compensating for pressure changes, continuing to produce shock wave pressure pulses of approximately the same wavelength as the pressure drop across the cells varies. Thus, the dimensions of the resonant cavities tend to remain matched to the wavelength of the pressure pulses despite fluctuations in the pressure of source 44.

In operation, resonant action in primary cavity 46 is enhanced by slot 54 and auxiliary cavity 53 because the metallic reflective surface of plate 43 is replaced by a fluidic reflective surface, namely, the fluid at the interface of slot 54 and primary cavity 46. The establishment of this fluidic reflective surface requires that the sum of X X,, be dimensionally related to the wavelength of the pressure pulses. In addition to its role in forming the fluidic reflective surface at the interface of primary cavity 46 and slot 54, auxiliary cavity 53 also functions to resonant pressure pulse energy coupled to it through slot 54. In this sense, auxiliary cavity 53 is connected in series with primary cavity 46. Some of the energy emitted from the ends of primary cavity 46 and auxiliary cavity 53 is intercepted by auxiliary cavities 47, 48, and 49, and auxiliary cavities 50, 51, and 52. Due to the dimensions of these cavities, it is believed resonant action of the intercepted energy takes place in three dimensions, namely, height, width, and depth. As a result, the energizing capability of the sonic wave energy emanating from holes 55 and 56 is even further enhanced and a more uniform standing wave field is formed across holes 55 and 56.

In FIG. 7, one arrangement of shock wave generator 13, coupling 14, and resonant cavity of the embodiment of FIG. 2 is shown in detail. Shock wave generator 13 comprises shock wave generating units 60 and 61, each of which could be identical to unit 39 in FIG. 6. A source 62 of fluid under pressure is joined to the inlets of units 60 and 61 by a Y connection 63 and the outlets of units 60 and 61 are joined by a Y connection 64 and a coupling 65 to an inlet conduit 66 formed in a metallic plate 67. Plate 67 has holes 68 and 69 through it. A primary resonant cavity 70 extends between holes 68 and 69, auxiliary resonant cavities 71, 72, and 73 are spaced at 90 intervals around hole 68, auxiliary resonant cavities 74, 75, and 76 are spaced at 90 intervals around hole 69, an auxiliary cavity 77 extends between holes 68 and 69, and a slot 78 connects cavities 70 and 77. Cavities 70, 71, 72, 73, 74, 75, 76, and 77, and slot 78 correspond to cavities 46, 47, 48, 49, 50, 51, 52, and 53, and slot 54, respectively, in FIG. 6, and are all dimensionally related to the basic wavelength of the shock wave pressure pulses. A primary conduit 80 connects inlet conduit 66 to primary cavity 70, and auxiliary conduits 81 and 82 connect inlet conduit 66 to cavities 72 and 75, respectively. Conduits 66, 80, 81, and 82 all have square cross sections with a linear side dimension (e.g., 0.180 inches) related to the linear cross-sectional dimensions of connection 64 (e.g., 0.180 inches), which has a circular or square cross section. Both linear dimensions are related to the basic wavelength of the shock wave pressure pulses (e.g., 0.180 inches). Coupling 14 of FIG. 2 is represented in FIG. 7 by connection 64 and conduits 66, 80,

81, and 82. The uniformity of the standing wave field produced by the plate configuration of FIG. 7 across holes 68 and 69 is even further enhanced, vis-a-vis the plate configuration of FIG. 6, by virtue of auxiliary conduits 81 and 82, which couple shock wave pressure pulses directly to auxiliary cavities 72 and 75. In effect, cavities and 72 are arranged in parallel to emit sonic wave energy into hole 68 at diametrically opposite points on its periphery and cavities 70 and are arranged in parallel to emit sonic wave energy into hole 69 at diametrically opposite points on its periphery. If primary cavity 70 were required to feed sonic wave energy into only one hole, it could be closed on one end, in which case it would essentially be the same as auxiliary cavities 72 and 75.

To energize a fluid with the arrangements in FIGS. 4 through 7, the fluid isdirected through the holes in the plate in a direction perpendicular to the plane of the plate. The fluid becomes energized as it passes through the standing wave field formed across the holes.

In FIG. 8 is shown an alternative arrangement of resonant cavity 12 of FIG. 2. The resonant cavity is formed in a plate 87 having holes 88 and 89 through it. A primary resonant cavity 90 is formed by a network of channels all preferably having square cross sections with a height Z, and a width Y, (e.g., Z,, Y, 0.180 inches). Primary cavity 90 includes a longitudinal channel 91 and a cross channel 92, which are perpendicular to each other and connected to each other at one end of channel 91. At its ends, channel 92 opens into holes 88 and 89 through exit channels 99 and 100, respectively. At its end opposite channel 92, channel 91 opens into both of holes 88 and 89 through an exit channel 101 with a depth X, (e.g., 0.180 inches). Auxiliary cavities 93 and 94 are distributed at 90 intervals from each other and from channels 99 and 101 about the periphery of hole 88 and auxiliary cavities 95 and 96 are distributed at 90 intervals from each other and from channels and 101 about-the periphery of hole 89. Cavities 93 through 96 are all preferably effectively hexahedral with a width Y height Z and depth X (e.g., Y Z X 0.180 inches), although their back surfaces are actually rounded to facilitate the machin ing operation required to form them. The radius of the rounded back surfaces of cavities 93 through 96 is preferably dimensionally related to the side dimensions of cavities 93 through 96 (e.g., 0.090 inches). Feed conduits 97 and 98 couple one or more shock wave generators (not shown in FIG. 8) to cross channel 92. By way of example, a single shock wave generating unit, similar to unit 60 or 61, could be connected to feed conduits 97 and 98 by a Y connection; or separate shock wave generating units could be connected directly to the respective feed conduits 97 and 98. Feed conduits 97 and 98 both preferably have round cross sections with a diameter D equal to the side dimensions X,, Y and Z of auxiliary cavities 93 through 96 and the side dimensions X,, Y,, and Z, of primary cavity 90 (e.g., D 0. l 80' inches). The wavelength or wavelengths produced by the shock wave generator is assumed to be 0.180 inches, multiples and submultiples thereof. The distances U and U along cross channel 92 between feed conduit 97 and longitudinal channel 91 and between feed conduit 97 and exit channel 99, respectively, and the distances V and V along cross channel 92 between feed conduit 98 and longitudinal channel 91 and between feed conduit 98 and exit channel 100, respectively, are all preferably multiples of the width Y and height Z of the channels (e.g., U, U, V, V =0.540 inches). The cross-sectional dimensions Y,, Z,, X Y Z X and D and the longitudinal dimensions U, U, V, V are significant. Intersections occur where feed conduits 97 and 98 meet cross channel 92, where longitudinal channel 91 meets exit channel 101, and where cross channel 92 meets exit channels 99 and 100. It has been found that spacing feed conduits 97 and 98 relative to channels 91, 99, and 101 in the described manner has a metering effect. In other words, the resonant cavity tends to reduce the variations in flow rate as a function of the pressure drop, particularly when the pressure drop variations are produced by changes in the downstream pressure, i.e., the pressure within holes 88 and 89, as in the intake system of an automobile engme.

FIGS. 9A and 9B show another alternative arrangement of resonant cavity 12 of FIG. 2 that exerts an even stronger metering effect than the arrangement of FIG. 8. A network 105 of channels is formed by grooves on one side of a metallic plate 106 and the adjacent side of a metallic plate 107, which is clamped to plate 106 by fasteners 108, 109, 110, and 111. Network 105, which is constructed in clamped plates 106 and 107 only for ease of .proto-type fabrication, could be formed in any other type of convenient structure. Network 105 comprises a circular channel 112 that circumscribes an equilateral triangular channel 113, channels 114, 115, and'116 that connect circular channel 112 with the corners of triangular channel 113, and channels 117, 118, and 119 that connect the midpoints of the respective sides of triangular channel 113 with a transverse central passage 120. Passage 120 is defined by the inside surface of tubes passing through plates I06 and 107, respectively. A supersonic nozzle 112, which is preferably the cell disclosed in my U.S. Pat. No. 3,554,443, is press fitted into a counterbore of passage 120 in plate 106, so passage 120 communicates with the inlet of nozzle 122. It is assumed nozzle 122 is the cell disclosed in my U.S. Pat. No. 3,554,443 and has the dimensions disclosed therein. Air under pressure is supplied to central passage 120 to establish air flow in the direction of arrows 123v and 124. A bleed conduit 125 connects circular channel 112 to the exterior of plate 106 where air under pressure is supplied to bleed conduit 125 to establish air flow in the direction of an arrow 126. The channels of network 105 all preferably have a square cross section with a width Y and a height Z (e.g., Y, Z 0.]80 inches). The width Y and the height Z and the component wavelengths of the pressure pulse energy from nozzle 122 are preferably multiply related. The distances R, R, S, S, T, and T between the junctions of circular channel 112 with connecting channels 114, 115, and 116 and the junctions of triangular channel 113 with connecting channels 117, 118, and 119 are all preferably multiples of the width Y and height Z of the channels (e.g., R, R, S, S, T, T L080 inches). As a result of the dimensional interrelationships, the energy of the fluid stream flowing through central passage 120 is converted into sonic wave energy having high energizing capability.

The diameter of bleed conduit 125 is also preferably dimensionally related to the Y and Z dimensions of the channels (e.g., 0.090 inches). A small stream of air flowing through bleed conduit 125 serves to enhance the energizing capability of the sonic wave energy produced by the described arrangement. Even though nozzle 122 is located downstream of network 105, it is believed that pressure pulses are coupled from nozzle 122 to network against the general flow of fluid, so the operation described in connection with FIG. 2 basically applies. The dimensions X, Y, Z, R, R, S, S, T, T,

In FIG. 10 there is shown a modification of the arrangement of FIGS. 9A and 9B based on the embodi ment of FIG. 1. Conduit 125 preferably is expanded to have a diameter equal to the Y and Z dimension (e.g., 0.180 inches), the portion of central passage in plate 107 is eliminated, and no supersonic nozzle is employed. The only passage for air flow in this arrangement is from conduit through the entire network of channels. It should be noted that network 105 can be considered to be an extension of the principle of the network comprising conduits 97 and 98 and channels 91, 99, 101, and 92, which correspond, for example, respectively to channels 115, 114, 117, 118, 119 and the portion of channel 113 between channels '117 and 118 and channels 118 and 119. Further, pressure pulses generated in bleed conduit 125 are coupled to circular channel 112 in a directiontransverse to its length at the point where bleed conduit 125 meets circular channel 112. In addition to providing a very=long resonant cavity, i.e., essentially the sum of the perimeters of circular channel 112 and triangular channel 113, network 105 also provides many intersections, namely, intersections where channels 114, 115, and 116 connect channel 112 to channel 113, and where channels 117, 118, and 119 join channel 113.

A transverse resonant cavity comprising a three dimensional network of channels, i.e.., a network that extends into two or more stacked planes, can be formed in a compact package. FIGS. 11A and 11B disclose resonant cavity 15 of FIG. 1 in such a package. In FIG. 11A, plates 132, 133, 134, 135, and 136 are shown in an unassembled condition. In FIG. 11B, plates 132 through 136 are shown in an assembled condition, one variation comprising plates133, 135, and 132, another variation comprising plates 133, 136, and 134. A shock wave generating cell 137 as disclosed in U.S. Pat. No. 3,554,443, is attached to plate 133, and a fitting 138 is attached to plate 132 or 134. A square channel 139 and a transverse central passage 140 are formed in plate 132. Channels 141, 142, 143, and 1144 connect square channel 139 to central passage 140. A circular channel and a transverse central passage 146 are formed in plate 133. A bleed conduit 147 couples circular channel 145 to the perimeter of plate 133. Plate 135 has connecting conduits 148, 149, 150, and 151, and a central passage 152. The outer diameter of circular channel 145 equals the outer side dimension of square channel 139. When plates 132, 135, and 133 are stacked oneon top of the other in the order recited so the surfaces of plates 132 and 133 shown in FIG. 11A face each other, square channel 139, connecting conduits 148 through 151, and circular channel 145 are aligned to form a single interconnected network, and central passages 140, 152, and 146 are aligned to form a straight unobstructed passage between nozzle 137 and fitting 138.

An equilateral triangular channel 153 and a transverse central passage 154 are formed in plate 134. Channels 155, 156, and 157 connect triangular channel 153 to central passage 154. Plate 136 has connecting conduits 158, 159, and 160, and a central passage 161. The outer radius of circular channel 145 equals the distance from the midpoint of one side of the outer perimeter of triangular channel 153 to the centerpoint of central passage 154, i.e., triangular channel 153 circumscribes circular channel 145. When plate 133, 136, and 134 are stacked one on top of the other in the order recited so the surfaces of plates 133 and 134 shown in FIG. 11A face each other, circular channel 145, connecting conduits 158 through 160, and triangular channel 153 are all aligned to form a single interconnected network, and central passages 146, 161, and 154 are all aligned to form a straight unobstructed passage between nozzle 137 and fitting 138. Channels 139, 141 through 144, 145, 153, and 154 through 157 all preferably have square cross sections with a width Y and a height Z (e.g., Y, Z =0. l 80 inches). Connecting conduits 148 through 151 and 158 through 160 all preferably have circular cross sections with a diameter D, equal to the width Y and height Z of the channels (e.g., D =0.l80 inches). Bleed conduit 147 preferably has a circular cross section D with a diameter equal to one-half of the width Y and the height Z of the channels (e.g., D 0.090 inches). The distances L and L between intersections of square channel 139, the diameter M of circular channel 145, and the distances N and N between intersections of triangular channel 153 are all preferably multiples of the width Y and the height Z ofthe channels (e.g., L, L =0.540 inches, M 1.08 inches, and N, N =0.900 inches). As illustrated by the exemplary dimensions, the multiple is most advantageously at least three. The dimensions Y, Z, D D L, L, M, N, and N are all significant. Central passages 140, 146, 152, 154, and 151, whose dimensions are not significant, all preferably have circular cross sections with a diameter that is large enough to permit the desired fluid flow rate.

In general, it has been found that the propagating range of the sonic wave energy and its energizing capability, as measured by the improvement in an internal combustion process, is direclty related to the number of intersections and the length of the network of channels. These factors apparently enhance the resonant action in the cavity. Thus, a network of channels arranged in stacked planes can produce very intense sonic waves because of the additional intersections formed by the connections between the channels in the different planes, and because of the capability to increase the length of the network by stacking more planes of channels on top of each other. It is believed that the more intersections and the greater the length of the network of channels that the fluid molecules must traverse, the more aligned these molecules become, i.e., the more coherent is the sonic wave energy.

It has been found that to achieve a given energizing capability, the number of intersections and the length of the network can be reduced by preconditioning the fluid with a supersonic nozzle. In FIG. 12 is disclosed a compact sonic wave generator based on this principle. A network 170 is formed in a metallic plate 171, which is shown in cross section in FIG. 12. Network 170 comprises a circular channel 172 and straight channels 173 and 174 extending from opposite sides of channel 172 to the exterior of plate 171. Channels 172, 173, and 174 all preferably have square cross sections with a width Y and a height Z (e.g., Y, Z 0.180 inches). The outer diameter J of circular channel 172 is preferably a multiple of the width Y and the height Z of the channels (e.g., J 0.900 inches). The lengths K and K of channels 173 and 174, respectively, are preferably amultiple of the width Y and the height Z of the channels (e.g., K, K 0.360 inches). A supersonic nozzle 175, which is preferably the cell disclosed in my US. Pat. No. 3,554,443, is attached to plate 171 so the nozzle outlet communicates with channel 173. A fluid under pressure is applied to the inlet of supersonic nozzle 175 to cause fluid flow through nozzle 175 and network to the exterior of plate 171 at straight channel 174. It is assumed that nozzle is designed to produce shock waves having wavelength components that are multiples or submultiples of 0.180 inches. Thus, nozzle 175 and network 170 are dimensionally matched. It is believed that nozzle 175 functions to align the fluid molecules to some extent before they enter network 170, so close alignment results even though network 170 is not very long.

It is emphasized that FIGS. 48, 5, 6, 7, 8, and 12 are sectional views. As illustrated in FIG. 4A for cavity 32, all the conduits, channels, and cavities shown in these sectional views are in fact closed on the side that lies in the sectional plane. They could be closed by the structure of the plate itself as in FIG. 4A, by another plate as in FIG. 9B, or by a thin gasket or the like.

As illustrated by the preceding description of the various embodiments and arrangements of the invention, there is a dimensional relationship among the significant dimensions of the resonant cavity, the crosssectional dimensions of the conduit, and the wavelength or wavelength components of the pressure pulses. Broadly, the rule to follow is that the significant dimensions of the resonant cavity and the wavelength or wavelength components of the pressure pulses to be resonated are multiples of a common divisor. For example, if the resonant cavity is a channel having a square cross section with a side dimension of 0.270 inches and the pressure pulses have a wavelength of 0. l 80 inches, the common divisor is 0.090 inches, the cross-sectional side dimension is a multiple of three, and the pressure pulse wavelength is a multiple of two. More specifically, the significant cross-sectional dimensions of the cavity and the wavelength or componentwavelengths of the pressure pulses are preferably multiply related. The multiple is as close to one as practical. If it is practical to make the multiple one, the cross-sectional dimensions of the cavity and the pressure pulse wavelength are equal. The significant longitudinal dimensions of the cavity between intersections are in most cases preferably a multiple of at least three of the cross-sectionaldimensions of the cavity. In practice, resonance is not completely destroyed until the significant dimensions of the resonant cavity deviate from the wavelength of the pressure pulses by onequarter wavelength. As a design guide, when the actual dimensional relationships for pressure pulse wavelength and the significant dimensions of the cavity are met to within :t 10 percent of the prescribed nominal values, the described results are in fact achieved. Beyond a i 10 percent deviation, the results drop off but are still usable.

The described embodiments of the invention are only considered to be preferred and illustrative of the inventive concept; the scope of the invention is not to be restricted to such embodiments. Various and numerous other arrangements may be devised by one skilled in the art without departing from the spirit and scope of this invention. For example,.any of the resonant cavity arrangements disclosed in FIGS. 4 through 12 could be used in any of the embodiments of FIGS. 1 through 3. A metallic plate is simply illustrated as a convenient structure for the formation of the cavities and conduits. A suitable metal for the plate is a free machining aluminum such as that bearing the grade designation 60-61. Other structures and materials such as plastic could be employed, depending upon the particular application at hand. Moreover, a downstream vacuum source is equivalent to the upstream source of fluid under pressure disclosed herein. Further, any of the conduits or cavities could be provided with other cross-sectional shapes or dimensions as long as the significant dimensions are matched to the wavelength of the pressure pulses so that resonant action takes place. Thus, the resonant cavities could have circular cross sections, although rectangular is preferable. In extending the principles represented in FIGS. 9 through 12, transverse resonant cavities in numerous other network arrangements can be constructed. For example, a network could comprise a circular channel that circumscribes a square channel, both being either in the same plane as depicted in FIG. 26 of application Ser. No. 158,915, filed July 1, 1971, or in stacked planes as depicted in FIG. 11A. If a stacked network of channels is used there are no known limitations on the number or variety of stacked channels. If the network includes a polygonal channel, e.g., a square or triangle, it is preferable to locate the entrance and/or exit conduits of the channel distances from the polygonal corners that are respectively multiples of a linear cross-sectional dimension of the channels comprising the network. The invention has applicability in fluids generally, liquids as well as gases.

What is claimed is:

l. A sonic wave generator comprising:

means for forming an elongated conduit, the conduit having an inlet end, an outlet end, and a longitudinal axis;

means for forming an elongated resonant cavity connected to the outlet end of the conduit, the cavity having a rectangular cross section and a longitudinal axis that is generally transverse to the axis of the conduit at the point where the cavity is connected to the outlet end of the conduit, a linear cross-sectional dimension of the conduit and a linear cross-sectional side dimension of the cavity being multiples of a common divisor;

means for forming an exit from the cavity for the emission of sonic wave energy;

a source of fluid coupled to the inlet end of the conduit; and

means for producing a pressure drop between the source and the exit from the cavity to induce fluid flow from the source through the conduit and cavity so as to generate pressure wave energy at the exit from the cavity, the source providing to the inlet end of the conduit a stream of supersonic fluid that produces shock wave pressure pulses having a wavelength that is a multiple of the common divisor.

2. The sonic wave generator of claim 1, in which the means source of fluid comprises a cylindrical passage through which the fluid flows and means for forming a converging-diverging fluid boundary layer in the passage, the dimensions of the boundary layer compensating for changes in the pressure drop of the pressure drop producing means such that the wavelength of the shock waves coupled to the cavity remains approximately constant.

3. The sonic wave generator of claim 2, in which the cylindrical passage comprises a nozzle body open at its downstream end, bounded along its length by a sidewall, and bounded at its upstream end by an end wall having a large center hole; and the means for forming a boundary layer comprises a plurality of smaller equally spaced peripheral holes disposed about the center hole in the end wall in oppositely arranged pairs, a plurality of oppositely disposed pairs of throat plane stabilizing holes lying in a common plane in the sidewall near the downstream end of the nozzle body, and a cylindrical cell cover enclosing the nozzle body to form an annular region surrounding the sidewall of the nozzle body, the cell cover completely enclosing the nozzle body except for an opening at its upstream end that communicates with the holes of the nozzle body and the open downstream end of the nozzle body.

4. The sonic wave generator of claim 3, in which the dimensions of the holes and the cell cover are selected so all the component wavelengths of the pressure pulses produced in the nozzle body are multiply related.

5. The sonic wave generator of claim 4, in which the resonant cavity has a square cross section, the crosssectional side dimensions of the cavity and the linear cross-sectional dimension of the conduit being dimensionally related to the component: wavelengths of the pressure pulses produced in the nozzle body.

6. The sonic wave generator of claim 5, in which the center hole has a diameter of 0.177 inches, the peripheral holes have a diameter of 0.031 inches, and the throat plane stabilzing holes have a diameter of 0.093 inches, the cross-sectional side dimensions of the cavity and the linear cross-sectional dimension of the conduit are in the range of 0.170 to 0.195 inches.

7. The sonic wave generator of claim 1, in which the resonant cavity has a square cross section.

8. The sonic wave generator of claim 1, in which the conduit and the cavity have square cross sections, the cross-sectional side dimension of which are equal.

9. The sonic wave generator of claim 1, in which the conduit has a circular cross section and the cavity has a square cross section, the cross-sectional diameter of the conduit and the cross-sectional side dimension of the cavity being equal.

- 10. The sonic wave generator of claim 1, in which the cavity is a primary cavity having a rectangular cross section formed in a body member; and the body member has a wall defining an enlarged at least partially enclosed space that communicates with the exit from the primary cavity and at least one hexahedral auxiliary resonant cavity formed in the wall, the auxiliary resonant cavity having hexahedral side dimensions that are related to the cross-sectional side dimensions of the cavity.

11. The sonic wave generator of claim 10, in which the'cross-sectional side dimensions of the primary cavity and the side dimensions of the auxiliary cavity are equal.

12. The sonic wave generator of claim 1, in which the conduit is a primary conduit and the cavity is a primary cavity having a rectangular cross section formed in a body member; and the body member has a wall defining an enlarged at least partially enclosed space that communicates with the exit from the primary cavity, at least one hexahedral auxiliary resonant cavity formed in the wall in communication with the enclosed space, and an auxiliary conduit formed in the body member. the auxiliary conduit having an inlet end coupled to the source of fluid and an outlet end connected to the auxiliary cavity, the auxiliary cavity having hexahedral side dimensions that are related to the cross-sectional side dimensions of the primary cavity.

13. The sonic wave generator of claim 12, in which the hexahedral side dimensions of the auxiliary cavity are related to the linear cross-sectional dimensions of the auxiliary conduit.

14. The sonic wave generator of claim 1, in which the conduit is a primary conduit and the cavity is a primary cavity having a rectangular cross section formed in a body member; the body member has an auxiliary resonant cavity with a rectangular cross section formed transverse to the primary conduit such that the primary cavity lies between the primary conduit and the auxiliary cavity and an auxiliary conduit formed between the primary cavity and the auxiliary cavity, the crosssectional side dimensions of the auxiliary cavity being related to the cross-sectional side dimensions of the primary cavity.

15. The sonic wave generator of claim 14, in which the linear cross-sectional dimensions of the auxiliary conduit and the distance from the interface between the primary cavity and the auxiliary conduit to the interface between the auxiliary conduit and the auxiliary cavity are related to the cross-sectional side dimensions of the primary cavity.

16. The sonic wave generator of claim 1, in which the resonant cavity comprises a cross channel; the exit from the cavity comprises a first channel, a second channel, and a third channel extending transversely from the cross channel at spaced intervals; and the conduit comprises first and second subconduits extending transversely into the cross channel between the first and second exit channels and the second and third exit channels, respectively, the distances along the cross channel between the first exit channel and the first subconduit, between the first subconduit and the second exit channel, between the second exit channel and the second subconduit, and between the second subconduit and the third exit channel being related to the cross-sectional dimensions of the cross channel and'the first, second, and third exit channels.

17. The sonic wave generator of claim 16, in which the resonant cavity is formed in a body member and first and second adjacent holes are formed in the body member such that the first and second exit channels communicate with the first hole and the second and third exit channels communicate with the second hole, the channels of the resonant cavity have a square crosssection, the cross-sectional side dimension of the cavity is equal to the linear cross-sectional dimension of the subconduits, and the distances along the cross channel are each a multiple of the cross-sectional side dimension of the resonant cavity.

18. The sonic wave generator of claim 17, additionally comprising means for forming first and second approximately hexahedral auxiliary resonant cavities in the body member in communication with the first hole, the first and second hexahedral cavities and the first and second exit channels being distributed around the first hole at approximately intervals, and means for forming third and fourth hexahedral auxiliary resonant cavities in the body member in communication with the second hole, the third and fourth hexahedral cavities and the second and third exit channels being distributed around the second hole at approximately 90 intervals.

19. The sonic wave generator of claim 1, in which the resonant cavity comprises a channel that forms a closed geometric network.

20. The sonic wave generator of claim 1, in which the resonant cavity comprises a network of closed geometric channels interconnected to each other.

21. The sonic wave generator of claim 20, in which the closed geometric channels are stacked in different planes.

22. The sonic wave generator of claim 20, in which one of the closed geometric channels is triangular and another of the closed geometric channels is circular, the circular channel circumscribing the triangular channel and interconnecting therewith at the corners of the triangular channel, and the exit comprises an outlet passage disposed within the triangular channel and first, second, and third exit channels extending transversely from the triangular channel midway between the respective corners thereof into the outlet passage.

23. The sonic wave generator of claim 22, in which the channels of the resonant cavity all have a square cross section and the distances from the respective corners of the triangular channel to the exit channels are multiples of the cross-sectional side dimension of the resonant cavity.

24. The sonic wave generator of claim 1, in which the resonant cavity comprises a circular channel, the feed conduit and the exit being disposed on diametrically opposite sides of the circular channel.

25. The sonic wave generator of claim 23, in which the circular channel has a square cross section; the feed conduit has a square cross section; the exit comprises a channel extending transversely from the circular channel and having a square cross section; the crosssectional side dimension of the feed conduit, the circular channel, and the exit channel are equal; and the length of the feed conduit and the exit channel are multiples of the cross-sectional side dimension of the circular channel.

26. The sonic wave generator of claim 25, additionally comprising:

a shock wave generating cell coupling the source of fluid to the inlet end of the conduit, the cell comprising a cylindrical nozzle body open at its end adjacent to the inlet end of the conduit, bounded along its length by a sidewall, and bounded at its other end by an end wall having a large center hole;

a plurality of smaller equally spaced peripheral holes disposed about the center hole in the end wall in oppositely arranged pairs;

a plurality of pairs of oppositely disposed throat plane stabilizing holes lying in a common plane in the sidewall near the inlet end of the conduit; and

a cylindrical cell cover'enclosing the nozzle body to form an annularregion surrounding the cylindrical sidewall of the nozzle body, the cell cover completely enclosing the nozzle body except for its open end and an opening at its upstream end that communicates with the holes of the nozzle body, the diameter of the center hole, the peripheral holes, and the throat plane stabilizing holes and the cross-sectional side dimension of the channels being multiply related.

27. A sonic wave generator comprising:

a body member in which a resonant cavity is formed,

the cavity having uniform rectangular crosssectional dimensions transverse to an axis along which the cavity extends and an exit for the emission of sonic wave energy; and

means for coupling to the resonant cavity periodic pressure pulses having at least one component wavelength that is dimensionally related to a linear cross-sectional side dimension of the cavity to cause resonance of such pressure pulses in the cavity and emit sonic wave energy from the exit of the cavity, the component wavelength and the side dimension of the cavity being multiples of a common divisor.

28. The sonic wave generator of claim 27, in which the cavity has a square cross-section, the crosssectional side dimension of the cavity and the component wavelength of the periodic pressure pulses being multiply related.

29. The sonic wave generator of claim 27, in which the linear cross-sectional side dimension of the cavity and the component wavelength of the pressure pulses are multiply related.

30. The sonic wave generator of claim 27, in which the coupling means comprises an elongated conduit connected to the cavity, the conduit being disposed along a longitudinal axis perpendicular to the axis of the resonant cavity where connected thereto, the conduit and the cavity having a linear cross-sectional dimension related to each other, and a source of fluid under pressure applied to the conduit.

31. The sonic wave generator of claim 27, in which the coupling means comprises a source of fluid, a cylindrical nozzle body having a downstream end in communication with the resonant cavity and an upstream end in communication with the source, there being a pressure drop between the source and the exit of the cavity, the nozzle body being open at its downstream end, bounded along its length by a sidewall, and bounded at its upstream end by an end wall having a large center hole, a plurality of smaller equally spaced peripheral holes disposed about the center hole in the end wall in oppositely arranged pairs, a plurality of oppositely disposed pairs of throat plane stabilizing holes lying in a common plane in the sidewall near the downstream end of the nozzle body, and a cylindrical cell cover enclosing the nozzle body to form an annular region surrounding the cylindrical sidewall of the noule body, the cell cover completely enclosing the nozzle body except for the open downstream end of the nozzle body and an opening at its upstream end that communicates with the holes of the nozzle body, the holes of the nozzle body all having dimensionally related diameters.

32. A sonic wave generator comprising:

a conduit having an inlet and an outlet, the conduit being disposed along a longitudinal axis;

an elongated resonant cavity disposed along a longitudinal axis, a linear cross-sectional dimension of the conduit and the cavity being multiples of a common divisor;

a junction where the outlet of the conduit communicates with the cavity, the axes of the conduit and cavity being transverse to each other at the junction;

means for propagating through the conduit to the resonant cavity pressure pulses having at least one component wavelength dimensionally related to the linear cross-sectional dimension of the conduit to produce sonic wave energy in the cavity, the one component wavelength and the linear crosssectional dimension of the conduit being multiples of a common divisor; and

means for coupling the sonic wave energy out of the cavity.

33. The sonic wave generator of claim 32, in which the component wavelength of the pressure pulses and the linear cross-sectional dimension of the conduit are multiply related.

34. The sonic wave generator of claim 33, in which the linear cross-sectional dimension of the conduit and the cavity are multiply related.

35. The sonic wave generator of claim 34, in which the resonant cavity has a square cross section, the cross-sectional side dimension of the cavity and the linear cross-sectional dimension of the conduit being multiply related.

36. The sonic wave generator of claim 35, in which the multiple is one.

37. A sonic wave generator comprising:

a plate having a hole through it;

a resonant cavity formed in the plate, the cavity being disposed on a longitudinal axis and having one open end that communicates with the hole; and

an elongated conduit formed in the plate along a longitudinal axis, the conduit having an inlet end and an outlet end communicating with the cavity at a point such that the axes of the cavity and the conduit are perpendicular to each other, a linear cross sectional dimension of the conduit and the cavity being related.

38. The sonic wave generator of' claim 37, in which the cavity is a primary cavity and the plate has a plurality of auxiliary cavities disposed about the periphery of the hole in communication with the space enclosed by the hole, a linear dimension of the auxiliary cavities being related to the linear cross-sectional dimension of the primary cavity.

39. The sonic wave generator of claim 37, additionally comprising another hole through the plate, the cavity having another open end that communicates with the other hole.

40. A sonic wave generator comprising:

a body member;

first and second adjacent holes formed in the body member;

a resonant cavity having a square cross section formed'in the body member, the cavity comprising a cross channel, a first exit channel connecting one end of the cross channel to the first hole, a second exit channel connecting the other end of the cross channel to the second hole, a longitudinal channel extendingtransversely from the cross channel intermediate the ends of the cross channel, and a third exit channel extending between the first and second holes to connect them to the longitudinal channel;

a first conduit extending transversely into the cross channel between the first exit channel and the longitudinal channel; and

a second conduit extending transversely into the cross channel between the longitudinal channel and the second exit channel, the distances along the cross channel between the first exit channel and the first conduit, between the first conduit and the longitudinal channel, between the longitudinal channel and the second conduit, and between the second conduit and the second exit channel being dimensionally related to the cross-sectional side dimension of the resonant cavity.

41. The sonic wave generator of claim 40, in which the distances along the cross channel are multiples of the cross-sectional side dimension of the resonant cavity.

42. The sonic wave generator of claim 40, in which the resonant cavity is a primary cavity and hexahedral auxiliary cavities are formed around the first and second holes, the auxiliary cavities having side dimensions that are multiples or submultiples of the cross-sectional side dimension of the primary resonant cavity.

43. A sonic wave generator comprising:

a body member;

an equilateral triangular channel formed in the body member;

a circular channel formed in the body member to circumscribe the triangular channel and to communicate with the triangular channel at its corners;

a central passage extending through the body member near the center of the triangular channel;

first, second, and third connecting channels extending between the center of the respective sides of the triangular channel and the central passage; and

a conduit extending from the exterior of the body member to the circular channel, the channels all having rectangular cross-sections, the crosssectional side dimensions of the channels, a linear cross-sectional dimension of the conduit, and the distance from the corners of the triangular channels to each connecting channel being multiply related.

44. A sonic wave generator comprising:

a body member;

a circular channel formed in the body member;

a first connecting channel extending from the exterior of the body memberradially to the circular channel;

a second connecting channel extending from the exterior of the body member radially to the circular channel at a point diametrically opposite from the first connecting channel, the channels all having square cross sections;

a cylindrical nozzle body having an upstream end exposed to the exterior of the body member and a downstream end communicating with the first connecting channel, the nozzle body being open at its downstream end, bounded along its length by a sidewall, and bounded at its upstream end by an end wall having a large center hole; a plurality of smaller equally spaced peripheral holes disposed about the center hole in the end wall arranged in oppositely disposed pairs; plurality of oppositely disposed pairs of throat plane stabilizing holes lying in a common plane in the sidewall near the downstream end of the nozzle body; and

a cylindrical cell cover enclosing the nozzle body to form an annular region surrounding the cylindrical sidewall of the nozzle body, the cell cover completely enclosing the nozzle body except for the open downstream end of the nozzle body and an opening at its upstream end that communicates with the holes of the nozzle body, the crosssectional side dimension of the channels and the diameters of the holes in the nozzle body being multiply related.

45. A sonic wave generator comprising:

a body member;

a hole formed in the body member;

A means for coupling sonic wave energy having a given wavelength into the hole; and

one or more hexahedral resonant cavities formed in the body member in communication with the hole, the side dimensions of the resonant cavity and the given wavelength being multiples of a common divisor.

46. A sonic wave generator comprising:

a body constructed of one or more component pieces;

a closed channel having a rectangular cross section formed in the body, the cross-sectional side dimensions of the channel being multiply related; and

means for applying and removing fluid from the channel.

47. The sonic wave generator of claim 46, additionally comprising another closed channel having a rectangular cross section formed in the body and means for interconnecting the two channels to form a single continuous network.

48. The sonic wave generator of claim 47, in which the two channels have different geometric shapes and one channel circumscribes the other.

49. The sonic wave generator of claim 47, in which the two channels lie in different planes.

50. A method for generating sonic wave energy, the method comprising the steps of:

producing pressure pulses having a given wavelength;

and

simultaneously resonating the pressure pulses in a first dimension between a first pair of parallel reflective surfaces and in a second dimension perpendicular to the first dimension between a second pair of parallel reflective surfaces to convert the pressure pulses into sonic wave energy, the first dimension, the second dimension, and the given wavelength being multiples of a common divisor.

51. The method of claim 50, in which the first and second dimensions and the given wavelength are multiply related.

52. A method of transmitting sonic wave energy from a first point to a second point, the method comprising the steps of:

generating at the first point pressure waves having a wavelength in a range substantially between 0.172 and 0.195 inches, multiples and/or submultiples thereof; and

channeling the pressure waves from the first point to the second point through a gaseous medium.

53. A method of extensively energizing a gaseous medium, the method comprising the steps of:

generating pressure wave energy having a plurality of multiply related wavelength components; and

releasing the pressure wave energy into the gaseous medium to propagate therethrough.

54. The method of claim 53, in which the wavelength components are in a range of 0.172 to 0.195 inches, multiples and/or submultiples thereof.

55. The method of claim 52, in which the pressure waves are channeled from the first point to the second point by a conduit, a linear cross-sectional dimension of the conduit and the wavelength of the pressure waves being multiples of a common divisor.

56. A sonic wave generator comprising:

a fluid source;

a fluid receiver at a lower pressure than the fluid source;

an elongated resonant channel having a rectangular cross section and a length many times larger than the linear cross-sectional side dimensions of the channel,

an exit leading from the channel to the fiuid receiver;

an elongated conduit having one end connected to the source and the other end connected to the channel at a point spaced along the length of the channel from the exit so all the fluid from the source passing through the conduit passes through the channel;

a linear cross-sectional side dimension of the channel and the linear cross-sectional side dimensions of the conduit being multiples of a common divisor.

Claims (56)

1. A sonic wave generator comprising: means for forming an elongated conduit, the conduit having an inlet end, an outlet end, and a longitudinal axis; means for forming an elongated resonant cavity connected to the outlet end of the conduit, the cavity having a rectangular cross section and a longitudinal axis that is generally transverse to the axis of the conduit at the point where the cavity is connected to the outlet end of the conduit, a linear cross-sectional dimension of the conduit and a linear crosssectional side dimension of the cavity being multiples of a common divisor; means for forming an exit from the cavity for the emission of sonic wave energy; a source of fluid coupled to the inlet end of the conduit; and means for producing a pressure drop between the source and the exit from the cavity to induce fluid flow from the source through the conduit and cavity so as to generate pressure wave energy at the exit from the cavity, the source providing to the inlet end of the conduit a stream of supersonic fluid that produces shock wave pressure pulses having a wavelength that is a multiple of the common divisor.

2. The sonic wave generator of claim 1, in which the means source of fluid comprises a cylindrical passage through which the fluid flows and means for forming a converging-diverging fluid boundary layer in the passage, the dimensions of the boundary layer compensating for changes in the pressure drop of the pressure drop producing means such that the wavelength of the shock waves coupled to the cavity remains approximately constant.

3. The sonic wave generator of claim 2, in which the cylindrical passage comprises a nozzle body open at its downstream end, bounded along its length by a sidewall, and bounded at its upstream end by an end wall having a large center hole; and the means for forming a boundary layer comprises a plurality of smaller equally spaced peripheral holes disposed about the center hole in the end wall in oppositely arranged pairs, a plurality of oppositely disposed pairs of throat plane stabilizing holes lying in a common plane in the sidewall near the downstream end of the nozzle body, and a cylindrical cell cover enclosing the nozzle body to form an annular region surrounding the sidewall of the nozzle body, the celL cover completely enclosing the nozzle body except for an opening at its upstream end that communicates with the holes of the nozzle body and the open downstream end of the nozzle body.

4. The sonic wave generator of claim 3, in which the dimensions of the holes and the cell cover are selected so all the component wavelengths of the pressure pulses produced in the nozzle body are multiply related.

5. The sonic wave generator of claim 4, in which the resonant cavity has a square cross section, the cross-sectional side dimensions of the cavity and the linear cross-sectional dimension of the conduit being dimensionally related to the component wavelengths of the pressure pulses produced in the nozzle body.

6. The sonic wave generator of claim 5, in which the center hole has a diameter of 0.177 inches, the peripheral holes have a diameter of 0.031 inches, and the throat plane stabilzing holes have a diameter of 0.093 inches, the cross-sectional side dimensions of the cavity and the linear cross-sectional dimension of the conduit are in the range of 0.170 to 0.195 inches.

7. The sonic wave generator of claim 1, in which the resonant cavity has a square cross section.

8. The sonic wave generator of claim 1, in which the conduit and the cavity have square cross sections, the cross-sectional side dimension of which are equal.

9. The sonic wave generator of claim 1, in which the conduit has a circular cross section and the cavity has a square cross section, the cross-sectional diameter of the conduit and the cross-sectional side dimension of the cavity being equal.

10. The sonic wave generator of claim 1, in which the cavity is a primary cavity having a rectangular cross section formed in a body member; and the body member has a wall defining an enlarged at least partially enclosed space that communicates with the exit from the primary cavity and at least one hexahedral auxiliary resonant cavity formed in the wall, the auxiliary resonant cavity having hexahedral side dimensions that are related to the cross-sectional side dimensions of the cavity.

11. The sonic wave generator of claim 10, in which the cross-sectional side dimensions of the primary cavity and the side dimensions of the auxiliary cavity are equal.

12. The sonic wave generator of claim 1, in which the conduit is a primary conduit and the cavity is a primary cavity having a rectangular cross section formed in a body member; and the body member has a wall defining an enlarged at least partially enclosed space that communicates with the exit from the primary cavity, at least one hexahedral auxiliary resonant cavity formed in the wall in communication with the enclosed space, and an auxiliary conduit formed in the body member, the auxiliary conduit having an inlet end coupled to the source of fluid and an outlet end connected to the auxiliary cavity, the auxiliary cavity having hexahedral side dimensions that are related to the cross-sectional side dimensions of the primary cavity.

13. The sonic wave generator of claim 12, in which the hexahedral side dimensions of the auxiliary cavity are related to the linear cross-sectional dimensions of the auxiliary conduit.

14. The sonic wave generator of claim 1, in which the conduit is a primary conduit and the cavity is a primary cavity having a rectangular cross section formed in a body member; the body member has an auxiliary resonant cavity with a rectangular cross section formed transverse to the primary conduit such that the primary cavity lies between the primary conduit and the auxiliary cavity and an auxiliary conduit formed between the primary cavity and the auxiliary cavity, the cross-sectional side dimensions of the auxiliary cavity being related to the cross-sectional side dimensions of the primary cavity.

15. The sonic wave generator of claim 14, in which the linear cross-sectional dimensions of the auxiliary conduit and the distance from the interface between the primary cavity and the auxiliary conduit to the interface between the auxiliary conduit and the auxiliary cavity are related to the cross-sectional side dimensions of the primary cavity.

16. The sonic wave generator of claim 1, in which the resonant cavity comprises a cross channel; the exit from the cavity comprises a first channel, a second channel, and a third channel extending transversely from the cross channel at spaced intervals; and the conduit comprises first and second subconduits extending transversely into the cross channel between the first and second exit channels and the second and third exit channels, respectively, the distances along the cross channel between the first exit channel and the first subconduit, between the first subconduit and the second exit channel, between the second exit channel and the second subconduit, and between the second subconduit and the third exit channel being related to the cross-sectional dimensions of the cross channel and the first, second, and third exit channels.

17. The sonic wave generator of claim 16, in which the resonant cavity is formed in a body member and first and second adjacent holes are formed in the body member such that the first and second exit channels communicate with the first hole and the second and third exit channels communicate with the second hole, the channels of the resonant cavity have a square cross-section, the cross-sectional side dimension of the cavity is equal to the linear cross-sectional dimension of the subconduits, and the distances along the cross channel are each a multiple of the cross-sectional side dimension of the resonant cavity.

18. The sonic wave generator of claim 17, additionally comprising means for forming first and second approximately hexahedral auxiliary resonant cavities in the body member in communication with the first hole, the first and second hexahedral cavities and the first and second exit channels being distributed around the first hole at approximately 90* intervals, and means for forming third and fourth hexahedral auxiliary resonant cavities in the body member in communication with the second hole, the third and fourth hexahedral cavities and the second and third exit channels being distributed around the second hole at approximately 90* intervals.

19. The sonic wave generator of claim 1, in which the resonant cavity comprises a channel that forms a closed geometric network.

20. The sonic wave generator of claim 1, in which the resonant cavity comprises a network of closed geometric channels interconnected to each other.

21. The sonic wave generator of claim 20, in which the closed geometric channels are stacked in different planes.

22. The sonic wave generator of claim 20, in which one of the closed geometric channels is triangular and another of the closed geometric channels is circular, the circular channel circumscribing the triangular channel and interconnecting therewith at the corners of the triangular channel, and the exit comprises an outlet passage disposed within the triangular channel and first, second, and third exit channels extending transversely from the triangular channel midway between the respective corners thereof into the outlet passage.

23. The sonic wave generator of claim 22, in which the channels of the resonant cavity all have a square cross section and the distances from the respective corners of the triangular channel to the exit channels are multiples of the cross-sectional side dimension of the resonant cavity.

24. The sonic wave generator of claim 1, in which the resonant cavity comprises a circular channel, the feed conduit and the exit being disposed on diametrically opposite sides of the circular channel.

25. The sonic wave generator of claim 23, in which the circular channel has a square cross section; the feed conduit has a square cross section; the exit comprises a channel extending transversely from the circular channel and having a square cross section; the cross-sectional side dimension of the feEd conduit, the circular channel, and the exit channel are equal; and the length of the feed conduit and the exit channel are multiples of the cross-sectional side dimension of the circular channel.

26. The sonic wave generator of claim 25, additionally comprising: a shock wave generating cell coupling the source of fluid to the inlet end of the conduit, the cell comprising a cylindrical nozzle body open at its end adjacent to the inlet end of the conduit, bounded along its length by a sidewall, and bounded at its other end by an end wall having a large center hole; a plurality of smaller equally spaced peripheral holes disposed about the center hole in the end wall in oppositely arranged pairs; a plurality of pairs of oppositely disposed throat plane stabilizing holes lying in a common plane in the sidewall near the inlet end of the conduit; and a cylindrical cell cover enclosing the nozzle body to form an annular region surrounding the cylindrical sidewall of the nozzle body, the cell cover completely enclosing the nozzle body except for its open end and an opening at its upstream end that communicates with the holes of the nozzle body, the diameter of the center hole, the peripheral holes, and the throat plane stabilizing holes and the cross-sectional side dimension of the channels being multiply related.

27. A sonic wave generator comprising: a body member in which a resonant cavity is formed, the cavity having uniform rectangular cross-sectional dimensions transverse to an axis along which the cavity extends and an exit for the emission of sonic wave energy; and means for coupling to the resonant cavity periodic pressure pulses having at least one component wavelength that is dimensionally related to a linear cross-sectional side dimension of the cavity to cause resonance of such pressure pulses in the cavity and emit sonic wave energy from the exit of the cavity, the component wavelength and the side dimension of the cavity being multiples of a common divisor.

28. The sonic wave generator of claim 27, in which the cavity has a square cross-section, the cross-sectional side dimension of the cavity and the component wavelength of the periodic pressure pulses being multiply related.

29. The sonic wave generator of claim 27, in which the linear cross-sectional side dimension of the cavity and the component wavelength of the pressure pulses are multiply related.

30. The sonic wave generator of claim 27, in which the coupling means comprises an elongated conduit connected to the cavity, the conduit being disposed along a longitudinal axis perpendicular to the axis of the resonant cavity where connected thereto, the conduit and the cavity having a linear cross-sectional dimension related to each other, and a source of fluid under pressure applied to the conduit.

31. The sonic wave generator of claim 27, in which the coupling means comprises a source of fluid, a cylindrical nozzle body having a downstream end in communication with the resonant cavity and an upstream end in communication with the source, there being a pressure drop between the source and the exit of the cavity, the nozzle body being open at its downstream end, bounded along its length by a sidewall, and bounded at its upstream end by an end wall having a large center hole, a plurality of smaller equally spaced peripheral holes disposed about the center hole in the end wall in oppositely arranged pairs, a plurality of oppositely disposed pairs of throat plane stabilizing holes lying in a common plane in the sidewall near the downstream end of the nozzle body, and a cylindrical cell cover enclosing the nozzle body to form an annular region surrounding the cylindrical sidewall of the nozzle body, the cell cover completely enclosing the nozzle body except for the open downstream end of the nozzle body and an opening at its upstream end that communicates with the holes of the nozzle body, the holes of the nozzle body all having dimensionally related diameters.

32. A sonic wave generator comprising: a conduit having an inlet and an outlet, the conduit being disposed along a longitudinal axis; an elongated resonant cavity disposed along a longitudinal axis, a linear cross-sectional dimension of the conduit and the cavity being multiples of a common divisor; a junction where the outlet of the conduit communicates with the cavity, the axes of the conduit and cavity being transverse to each other at the junction; means for propagating through the conduit to the resonant cavity pressure pulses having at least one component wavelength dimensionally related to the linear cross-sectional dimension of the conduit to produce sonic wave energy in the cavity, the one component wavelength and the linear cross-sectional dimension of the conduit being multiples of a common divisor; and means for coupling the sonic wave energy out of the cavity.

33. The sonic wave generator of claim 32, in which the component wavelength of the pressure pulses and the linear cross-sectional dimension of the conduit are multiply related.

34. The sonic wave generator of claim 33, in which the linear cross-sectional dimension of the conduit and the cavity are multiply related.

35. The sonic wave generator of claim 34, in which the resonant cavity has a square cross section, the cross-sectional side dimension of the cavity and the linear cross-sectional dimension of the conduit being multiply related.

36. The sonic wave generator of claim 35, in which the multiple is one.

37. A sonic wave generator comprising: a plate having a hole through it; a resonant cavity formed in the plate, the cavity being disposed on a longitudinal axis and having one open end that communicates with the hole; and an elongated conduit formed in the plate along a longitudinal axis, the conduit having an inlet end and an outlet end communicating with the cavity at a point such that the axes of the cavity and the conduit are perpendicular to each other, a linear cross-sectional dimension of the conduit and the cavity being related.

38. The sonic wave generator of claim 37, in which the cavity is a primary cavity and the plate has a plurality of auxiliary cavities disposed about the periphery of the hole in communication with the space enclosed by the hole, a linear dimension of the auxiliary cavities being related to the linear cross-sectional dimension of the primary cavity.

39. The sonic wave generator of claim 37, additionally comprising another hole through the plate, the cavity having another open end that communicates with the other hole.

40. A sonic wave generator comprising: a body member; first and second adjacent holes formed in the body member; a resonant cavity having a square cross section formed in the body member, the cavity comprising a cross channel, a first exit channel connecting one end of the cross channel to the first hole, a second exit channel connecting the other end of the cross channel to the second hole, a longitudinal channel extending transversely from the cross channel intermediate the ends of the cross channel, and a third exit channel extending between the first and second holes to connect them to the longitudinal channel; a first conduit extending transversely into the cross channel between the first exit channel and the longitudinal channel; and a second conduit extending transversely into the cross channel between the longitudinal channel and the second exit channel, the distances along the cross channel between the first exit channel and the first conduit, between the first conduit and the longitudinal channel, between the longitudinal channel and the second conduit, and between the second conduit and the second exit channel being dimensionally related to the cross-sectional side dimension of the resonant cavity.

41. The sonic wave generator of claim 40, in which the distances along the cross channel are multiples of the cross-sectional side dimension of the rEsonant cavity.

42. The sonic wave generator of claim 40, in which the resonant cavity is a primary cavity and hexahedral auxiliary cavities are formed around the first and second holes, the auxiliary cavities having side dimensions that are multiples or submultiples of the cross-sectional side dimension of the primary resonant cavity.

43. A sonic wave generator comprising: a body member; an equilateral triangular channel formed in the body member; a circular channel formed in the body member to circumscribe the triangular channel and to communicate with the triangular channel at its corners; a central passage extending through the body member near the center of the triangular channel; first, second, and third connecting channels extending between the center of the respective sides of the triangular channel and the central passage; and a conduit extending from the exterior of the body member to the circular channel, the channels all having rectangular cross-sections, the cross-sectional side dimensions of the channels, a linear cross-sectional dimension of the conduit, and the distance from the corners of the triangular channels to each connecting channel being multiply related.

44. A sonic wave generator comprising: a body member; a circular channel formed in the body member; a first connecting channel extending from the exterior of the body member radially to the circular channel; a second connecting channel extending from the exterior of the body member radially to the circular channel at a point diametrically opposite from the first connecting channel, the channels all having square cross sections; a cylindrical nozzle body having an upstream end exposed to the exterior of the body member and a downstream end communicating with the first connecting channel, the nozzle body being open at its downstream end, bounded along its length by a sidewall, and bounded at its upstream end by an end wall having a large center hole; a plurality of smaller equally spaced peripheral holes disposed about the center hole in the end wall arranged in oppositely disposed pairs; a plurality of oppositely disposed pairs of throat plane stabilizing holes lying in a common plane in the sidewall near the downstream end of the nozzle body; and a cylindrical cell cover enclosing the nozzle body to form an annular region surrounding the cylindrical sidewall of the nozzle body, the cell cover completely enclosing the nozzle body except for the open downstream end of the nozzle body and an opening at its upstream end that communicates with the holes of the nozzle body, the cross-sectional side dimension of the channels and the diameters of the holes in the nozzle body being multiply related.

45. A sonic wave generator comprising: a body member; a hole formed in the body member; means for coupling sonic wave energy having a given wavelength into the hole; and one or more hexahedral resonant cavities formed in the body member in communication with the hole, the side dimensions of the resonant cavity and the given wavelength being multiples of a common divisor.

46. A sonic wave generator comprising: a body constructed of one or more component pieces; a closed channel having a rectangular cross section formed in the body, the cross-sectional side dimensions of the channel being multiply related; and means for applying and removing fluid from the channel.

47. The sonic wave generator of claim 46, additionally comprising another closed channel having a rectangular cross section formed in the body and means for interconnecting the two channels to form a single continuous network.

48. The sonic wave generator of claim 47, in which the two channels have different geometric shapes and one channel circumscribes the other.

49. The sonic wave generator of claim 47, in which the two channels lie in different planes.

50. A method for generating sonic wave energy, the method comprIsing the steps of: producing pressure pulses having a given wavelength; and simultaneously resonating the pressure pulses in a first dimension between a first pair of parallel reflective surfaces and in a second dimension perpendicular to the first dimension between a second pair of parallel reflective surfaces to convert the pressure pulses into sonic wave energy, the first dimension, the second dimension, and the given wavelength being multiples of a common divisor.

51. The method of claim 50, in which the first and second dimensions and the given wavelength are multiply related.

52. A method of transmitting sonic wave energy from a first point to a second point, the method comprising the steps of: generating at the first point pressure waves having a wavelength in a range substantially between 0.172 and 0.195 inches, multiples and/or submultiples thereof; and channeling the pressure waves from the first point to the second point through a gaseous medium.

53. A method of extensively energizing a gaseous medium, the method comprising the steps of: generating pressure wave energy having a plurality of multiply related wavelength components; and releasing the pressure wave energy into the gaseous medium to propagate therethrough.

54. The method of claim 53, in which the wavelength components are in a range of 0.172 to 0.195 inches, multiples and/or submultiples thereof.

55. The method of claim 52, in which the pressure waves are channeled from the first point to the second point by a conduit, a linear cross-sectional dimension of the conduit and the wavelength of the pressure waves being multiples of a common divisor.

56. A sonic wave generator comprising: a fluid source; a fluid receiver at a lower pressure than the fluid source; an elongated resonant channel having a rectangular cross section and a length many times larger than the linear cross-sectional side dimensions of the channel, an exit leading from the channel to the fluid receiver; an elongated conduit having one end connected to the source and the other end connected to the channel at a point spaced along the length of the channel from the exit so all the fluid from the source passing through the conduit passes through the channel; a linear cross-sectional side dimension of the channel and the linear cross-sectional side dimensions of the conduit being multiples of a common divisor.

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