US2718116A - Jet engine with coaxial fuel and air intake chambers - Google Patents

Description

C. J. MOSES Sept, 20, 1955 JET ENGINE WITH COAXIAL FUEL AND AIR INTAKE CHAMBERS 2 Sheets-Sheet l Filed April 20 1951 I INVENTOR C/M/PLESQ/ /Vosfs |1||||1I\\\ ..1111 I mwmw BY MCM/5mm nm ATTORNEYS C. J. MOSES sept. 2o, 1955 JET ENGINE WITH COAXIAL FUEL AND AIR INTAKE CHAMBERS Filed April 2O 1951 2 Sheets-Sheet 2 www;

INVENTOR CHA/nfs /Vosfs @Mia/am ATTORNEYS inited States Patent O JET ENGINE WITH COAXIAL FUEL'AND AIR INTAKE CHAMBERS Charles J. Moses, oak Hill, W.'va.

Application April 2o, 1951, serial No. 222,055

2 claims. (Cl. en -$9.71)

is simple in construction, which is compact in size, and f which is economical in consumption of fuel.

A further object of the invention is to provide an improved turbojet engine which involves relatively inexpensive parts, which is sturdy in construction, which includes means for heating the air drawn into the engine for combustion, whereby maximum efficiency is obtained in the combustion of the fuel employed, and whereby the weight of the engine may be reduced to a minimum.

Further objects and advantages of the invention will become apparent from the following description and claims, and from the accompanying drawings, wherein:

Figure l is a side elevational view of an engine constructed in accordance with the present invention, a portion of the engine wall being shown broken away.

Figure 2 is a longitudinal cross sectional view taken through the jet engine of Figure l.

Figure 3 is a transverse cross sectional view taken on the line 3-3 of Figure 2.

Figure 4 is a transverse cross sectional View taken on the line 4-4 of Figure 2.

Figure 5 is a transverse crosssectional view taken on the line 5 5 of Figure 2. A

Figure 5 is a transverse cross sectional view taken on the line 6 6 of Figure 2,.`

Figure 7 is an elevational view of the shaft of the engine of Figures 1 to 6.

Referring to the drawings, -the engine is designated generally at 11. Said engine comprises a main, elongated tubular housing 12 to the forward end of which is secured an annular body 13, and secured to said annular body at its forward side is the annular open nose casing 14. The body 13 is formed with a rearwardly directed reduced inner portion 15, and secured to said portion 15 are the alternating ring elements 16 and 17 defining a rearwardly extending inner casing disposed coaxially inside the main housing 12. The rear end of said inner casing comprises an annular ring member 18 which tapers rearwardly, as shown at 19. The members 13, 16,- 17 and 18 are secured together by longitudinally extending bolts 20 threadedly engaging in the end ring member 18 in the manner shown in Figure 2. The aforesaid casing defines an annular space 21 with respect to the main housing 12.

The rear end portion of housing 12 ares rearwardly in thickness, as shown at 22, and secured to said rear end portion are the successive turbine stator rings 23 and the open ended housing tail piece 24, a spacer ring 25 being interposed between the first turbine stator ring 23 and the rear end of the main housing 12, as shown in Figure 2. The members 23, 24 and 25 are secured to the rear end of main housing 12 by longitudinal bolts 26,

as shown.

ice

Designated at 27 is the engine shaft which is journaled at its end portions in the forward nose piece 14 and the rear tail piece 24, said shaft being rotatably supported in an axial position inside the engine. The shaft 27 is' pro'- vided with ya reduced forward portion 28 on which are secured the successive air compressor rotor members 29, each rotor member comprising a sleeve portion formed with a plurality of radially extending inclined vanes 30 which are disposed in the space defined between successive rings 16, as shown in Figure 2. Each ring 16 is formed with a plurality of inwardly projectingq radial vane elements 31. As shown in Figure 2, the lir'st *air compressor rotor 29 is disposed forwardly of the first ring member 16 and the last air compressor rotor 29 is disposed rearwardly of the last ring 16. Mounted orl the forward end of the reduced portion 28 is a conical collar 32. The air compressor rotor elements 29 are secured to the shaft 28 by a plurality of longitudinal bolts 33 extending longitudinally through collar 32 and the successive air compressor rotor elements 29, as shown, the bolts 33 being threadedly engaged in the intermediate portion of the shaft 27.

The shaft 27 flares rearwardly in thickness at 34 and is provided with the reduced rear portion 35. Mounted on rear portion 35 of the shaft are the successive turbine rotor elements 36 which are received within the respective turbine stator elements 23 and .which are secured to the shaft by a plurality of longitudinal bolts 37 extending through the respective turbine rotor elements 36 and threadedly engaging the thickened intermediate portion 34 of shaft 27 Disposed in the nose member 14 is the annular fuel supply conduit 38 which is connected to the source of fuel by means not shown, and connected to said supply conduit are a plurality of injection nozzles 39 secured iri and extending through the annular body 13, said nozzles being arranged to exhaust into the annular space 21.

In operation of the engine, fuel is injected into the space 21 through the nozzles 39 and moves rearwardly through said space into the combustion space 40 defined between the end piece 19 of the forward inner casing and the thickened portion 34 of shaft 27. Air enters the engine through the opening 41 of the nose member 14 and is propelled through the aforesaid forward casing by the air compressor rotor elements 29. The air enters the space 40 and mixes with the fuel. A suitable ignition element, not shown, is provided in the space 40' which ignites the explosive mixture. The gaseous products of combustion thus produced move through the turbine rotor members 36 and provide propelling force causing said rotor elements 36 to revolve at a high rate of speed. The exhaust gases pass through the successive turbine stages and leave the engine at the outlet opening 42 at the rear end of tail piece 24. The shaft 27 is driven by the propulsion torque produced by the gaseous products of combustion as they move through the successive turbine stages, whereby the rotating air compressor vanes 30 force air into the inner casing at the forward portion of the engine and drives said air under considerable pressure into the combustion space 40 for mixture with the fuel and for subsequent ignition. The inwardly projecting vane elements 31 produce turbulence and sufliciently retard the intake of air through the forward inner casing to allow said air to be preheated to a substantially elevated temperature as it progresses through the inner casing into the combustion space 40. By thus preheating the air maximum efficiency of combustion is provided, whereby the fuel is utilized to best advantage and the fuel requirements of the engine are minirrlized.

It will be noted that the flaring portion 34 of shaft 27 and the gradually thickened portion 22 of the housing 12 define an annular, gradually constricted passage through which the gaseous products of combustion ow on their way toward the iirst turbine stage of the engine. By thus gradually decreasing the cross sectional area of the passage for the gaseous products of combustion, the velocity of movement of said gaseous products is increased and said gaseous products of combustion engage the blades of the rst rotor 36 with a high degree of kinetic energy and transfer a large amount of said energy to the rotor blades. It will be understood that the gas ows rearwardly through the successive turbine stages and delivers successive amounts of kinetic energy to the rotor blades of the successive stages until a considerable amount of the useful energy of the gaseous products of combustion has been delivered to the rotor blades of the turbine stages.

It will be further noted that the tapered coniiguration or the end piece 18 of the inner casing at the forward portion of the rotor provides an exhaust section for the fuel which flares rearwardly in area, thereby producing a throttling action which assists the vaporization of the fuel as it enters the mixing and combustion space 40. The air delivered into the space 40 from the air compressor casing also passes through an exhaust passage of rearwardly flaring configuration, shown at 43, whereby throttling of the air also occurs which facilitates its mixing with the vaporized fuel in the space 4t) and which provides a more uniform intermixing of the fuel and air, thereby causing smoother combustion in space 40 when the fuel and air mixture is ignited.

While a speciiic embodiment of an improved engine for use in aircraft has been disclosed in the foregoing description, it will be understood that various modifications within the spirit of the invention may occur to those Skilled in the art. Therefore, it is intended that no limitations be placed on the invention except as defined by the scope of the appended claims.

What is claimed is:

1. A jet engine of the character described comprising an elongated, open ended tubular housing, a shaft journaled axially in said housing, an annular wall secured in the forward portion of said housing, a cylindrical, rearwardly extending casing carried by said wall around the forward portion of said shaft and defining an annular fuel intake space between said casing and the internal Wall surface of the housing, said annularwall closing said fuel intake space at its forward end, a plurality of air intake vanes on said shaft within said casing, a plurality of mating vanes on the casing, a plurality l I of annular turbme stators secured 1n the rear portion of said housing around said shaft, respective turbine rotors mounted on the rear portion of said shaft in the turbine stators, the rear end of the casing being spaced from said turbine rotors to define an annular combustion space in the intermediate portion of said housing, and fuel injection means carried by said annular wall and directed into said fuel intake space, said fuel injection means comprising a plurality of conduits passing through said annular wall and terminating rearwardly of said Wall, in respective fuel injection nozzles spaced forwardly of said combustion space.

2. A jet engine of the character described comprising an elongated open ended tubular housing, a shaft journaled axially in said housing, an annular wall secured in the forward portion of said housing, a cylindrical, rearwardly extending casing carried by said wall around the lforward portion of said shaft and deiining an annular fuel intake space between said casing and the internal wall surface of the housing, said annular wall closing said fuel intake space at the forward end, a plurality of air intake vanes on said shaft within said casing, a plurality of mating vanes on said casing, a plurality of annular turbine stators secured in the rear portion of said housing around said shaft, respective turbine rotors mounted on the rear portion of said shaft in the turbine stators, the rear end of the casing being spaced from said turbine rotors to define an annular combustion space in the intermediate portion of said housing, and fuel injection means carried by said annular wall and directed into said fuel intake space', said fuel injection means comprising a plurality of conduits passing through said annular wall and terminating, rearwardly of said wall, in respective fuel injection nozzles spaced forwardly of said combustion space, the wall of the housing in said combustion space being of gradually increasing thickness rearwardly and the shaft being of increasing diameter rearwardly in said combustion space, whereby said cornbustion space gradually diminishes rearwardly in cross sectional area toward said turbine rotors.

References Cited in the iile of this patent UNITED STATES PATENTS 798,855 Wentworth Sept. 5, 1905 2,438,247 Knudsen Mar. 23, 1948 2,509,890 Stalker May 30, 1950 2,570,847 Ovens Oct. 9, 1951 2,576,762 Lawter Nov. 27, 1951 FOREIGN PATENTS 585,398 Great Britain Feb. 6, 1947

Images