Disclosure of Invention
The invention provides a wide-frequency-band vibration-damping noise-reducing metamaterial multi-span beam structure, aiming at solving the problems that the band gap frequency range cannot be widened and the structural vibration amplitude cannot be attenuated in multiple frequency ranges by the multi-span beam structure in the prior art.
A wide-frequency-band vibration-damping noise-reducing metamaterial multi-span beam structure comprises a bottom plate, fixed supporting components, a long beam, M flexible supporting components and M +2 vibrators, wherein M is a positive integer; the bottom plate is a cuboid, the fixed supporting assembly is arranged at one end of the upper surface of the bottom plate, the M flexible supporting assemblies are equidistantly arranged on the upper surface of the bottom plate along the length direction of the bottom plate, the fixed supporting assembly and each flexible supporting assembly are fixedly connected with the bottom plate, the M +2 vibrators are equidistantly arranged on the lower surface of the long beam along the length direction of the long beam, each vibrator is fixedly connected with the lower surface of the long beam, the long beam is arranged on the fixed supporting assembly and the M flexible supporting assemblies, the long beam is fixedly bonded with the fixed supporting assembly and each flexible supporting assembly, and each supporting assembly is arranged between two adjacent vibrators;
furthermore, the fixed supporting assembly comprises a supporting cylinder A, a smooth circular ring A and two circular hole supporting steel plates, the two circular hole supporting steel plates are arranged oppositely, a through hole is formed in the upper portion of the side wall of each circular hole supporting steel plate, two ends of the supporting cylinder A are arranged in the through holes respectively, each end of the supporting cylinder A is in interference fit with one through hole, the smooth circular ring A is sleeved in the middle of the outer circular surface of the supporting cylinder A and is rotatably connected with the supporting cylinder A, the bottom surface of each circular hole supporting steel plate is fixedly connected to the upper surface of the bottom plate, and the axis of the supporting cylinder A is parallel to the wide edge of the upper surface of the bottom plate;
furthermore, the flexible supporting assembly comprises a supporting cylinder B, a smooth circular ring B and two long hole supporting steel plates, wherein the two long hole supporting steel plates are arranged oppositely, a horizontal strip-shaped hole is formed in the upper portion of the side wall of each long hole supporting steel plate, two ends of each supporting cylinder B are arranged in the horizontal strip-shaped holes respectively, each end of each supporting cylinder B is connected with one horizontal strip-shaped hole in a sliding mode, the smooth circular ring B is sleeved in the middle of the outer circular surface of each supporting cylinder B and is connected with the supporting cylinder B in a rotating mode, the bottom surface of each long hole supporting steel plate is fixedly connected to the upper surface of the bottom plate, and the axis of each long hole supporting steel plate is parallel to the wide edge of the upper surface of the;
furthermore, the length of a horizontal strip-shaped hole in the upper part of the side wall of the long hole supporting steel plate is L, and the value range of L is 8-12 mm;
further, the vibrator comprises a cylindrical rubber and a cylindrical steel block, one end of the cylindrical rubber is fixedly connected with one end of the cylindrical steel block, and the other end of the cylindrical rubber is fixedly connected with the lower surface of the long beam;
further, the diameter of the end face of the cylindrical rubber is smaller than that of the end face of the cylindrical steel block;
furthermore, the number M of the flexible supporting components ranges from 2 to 4;
further, the distance between the fixed support assembly and the adjacent flexible support assembly is L1, and the value range of L1 is 18-24 cm;
further, the distance between two adjacent flexible supporting components is L2, and the value range of L2 is 18-24 cm;
further, the distance between two adjacent vibrators is L3, and the value range of L3 is 18-24 cm.
Compared with the prior art, the invention has the following beneficial effects:
1. compared with the beam structure provided by the prior art, the invention ensures that the long beam can generate micro deformation at the supporting point of the round hole supporting steel sheet and can slide at the supporting point of the long hole supporting steel sheet, thereby realizing the periodic simple supporting boundary condition of the metamaterial multi-span beam.
2. Compared with the beam structure provided by the prior art, the invention has the advantages that the vibrator is added on the long beam, so that the vibration of the long beam can be attenuated in a certain frequency range.
3. Compared with the beam structure provided by the prior art, the beam structure provided by the invention has the advantages that the long beam is applied with periodic boundary conditions, and the vibration of the long beam can be attenuated at medium-high frequency.
4. Compared with the beam structure provided by the prior art, the invention can couple the local resonance band gap and the Bragg band gap, broaden the band gap frequency range and improve the vibration and noise reduction effect.
5. The invention has simple structure, convenient manufacture and low cost, and saves the expenses for scientific research.
Detailed Description
The first embodiment is as follows: the embodiment is described with reference to fig. 1, the broadband vibration-damping noise-reducing metamaterial multi-span beam structure includes a base plate 1, a fixed support assembly, a long beam 7, M flexible support assemblies and M +2 vibrators, where M is a positive integer; bottom plate 1 is the cuboid, fixed supporting component sets up the one end at 1 upper surface of bottom plate, M flexible supporting component sets up on the upper surface of bottom plate 1 along 1 length direction equidistance of bottom plate, and fixed supporting component and every flexible supporting component all with 1 fixed connection of bottom plate, M +2 oscillators set up on long roof beam 7's lower surface along long roof beam 7's length direction equidistance, and every oscillator is connected with long roof beam 7's lower fixed surface, long roof beam 7 sets up on fixed supporting component and M flexible supporting component, and long roof beam 7 bonds fixedly with fixed supporting component and every flexible supporting component, every supporting component sets up between two adjacent oscillators.
This embodiment every supporting component setting supporting component in between two adjacent oscillators include fixed supporting component and flexible supporting component, fixed supporting component and flexible supporting component's common point is when being used for supporting, fixed supporting component and flexible supporting component all with bottom plate 1 rigid connection, the difference lies in fixed supporting component when long roof beam 7 atress, support cylinder A9 only can interference fit with round hole supporting steel plate 2, can't produce the displacement, and flexible supporting component is when long roof beam 7 atress, support cylinder B4 and 3 sliding connection of slot hole supporting steel plate, can produce slight deformation and micro displacement, and then play the effect of buffering.
The second embodiment is as follows: the present embodiment will be described with reference to fig. 1 and 2, and the present embodiment is further limited to the fixing support assembly in the specific embodiment, in the present embodiment, the fixed supporting component comprises a supporting cylinder A9, a smooth circular ring A10 and two round hole supporting steel plates 2, the two round hole supporting steel plates 2 are oppositely arranged, the upper part of the side wall of each round hole supporting steel plate 2 is provided with a through hole, two ends of the supporting cylinder A9 are respectively arranged in one through hole, each end of the supporting cylinder A is in interference fit with one through hole, the smooth circular ring A10 is sleeved at the middle part of the outer circular surface of the supporting cylinder A9, and smooth ring A10 and support cylinder A9 rotate to be connected, and the lower surface of long roof beam 7 bonds on smooth ring A10, and the bottom surface rigid coupling of each round hole support steel sheet 2 is on the upper surface of bottom plate 1, and the axis of support cylinder A9 sets up with the broadside on bottom plate 1 upper surface parallel. Other components and connection modes are the same as those of the first embodiment.
In this embodiment, one end of the long beam 7 is bonded and fixed by the smooth ring a10, and the smooth ring a10 is rotationally connected with the support cylinder a9, so that when a certain point in the long beam 7 is stressed, the long beam 7 generates a small amount of deformation to decompose the force, and the smooth ring a10 is also affected by the component force and rotates a small amount along the component force direction, so that the stressed point of the long beam 7 is buffered, and the band gap frequency range is widened.
The third concrete implementation mode: the present embodiment is described with reference to fig. 1 and 2, and is further limited to the flexible support assembly of the second embodiment, in which, the flexible supporting component comprises a supporting cylinder B4, a smooth circular ring B8 and two long hole supporting steel plates 3, the two long hole supporting steel plates 3 are oppositely arranged, the upper part of the side wall of each long hole supporting steel plate 3 is provided with a horizontal strip-shaped hole, two ends of the supporting cylinder B4 are respectively arranged in the horizontal strip-shaped holes, each end of the supporting cylinder B4 is connected with a horizontal bar-shaped hole in a sliding way, the smooth circular ring B8 is sleeved at the middle part of the outer circular surface of the supporting cylinder B4, and the smooth circular ring B8 is rotatably connected with the supporting cylinder B4, the lower surface of the long beam 7 is bonded on the smooth circular ring B8, the bottom surface of each long hole supporting steel plate 3 is fixedly connected on the upper surface of the bottom plate 1, and the axis of each long hole supporting steel plate 3 is parallel to the wide edge of the upper surface of the bottom plate 1. Other components and connection modes are the same as those of the first embodiment.
In this embodiment, one end of the long beam 7 is bonded and fixed by the smooth ring B8, the smooth ring B8 is rotationally connected with the support cylinder B4, and both ends of the support cylinder B4 can move laterally in the horizontal strip-shaped hole, so that when a certain point in the long beam 7 is stressed, the long beam 7 can generate a slight amount of deformation to decompose the force, the smooth ring B8 can also be influenced by the component force and rotate slightly in the component force direction, so that the stressed point of the long beam 7 is buffered, and the support cylinder B4 can slide laterally in the horizontal strip-shaped hole under the action of the component force, thereby realizing the periodic simple supporting boundary condition of the metamaterial multi-span beam, the embodiment is combined with the second embodiment to form a complete support structure in the structural beam, one end of the long beam 7 must be supported by a fixed support component, rather than a flexible support component, and mainly plays a positioning role, if all the supporting components adopt flexible supports, the long beam 7 can horizontally slide when stressed, the stability is seriously influenced, and the effects of damping, widening band gap frequency range and attenuating the vibration amplitude of the structure in a plurality of frequency ranges cannot be achieved.
The fourth concrete implementation mode: the present embodiment is described with reference to fig. 1, and the present embodiment further defines the long hole supporting steel plate 3 described in the first embodiment, in the present embodiment, the length of the horizontal strip-shaped hole at the upper portion of the side wall of the long hole supporting steel plate 3 is L, and the range of the value of L is 8 to 12 mm. Other components and connection modes are the same as those of the third embodiment.
So set up, consider the structural performance of long roof beam 7, the motion range that is difficult for making support cylinder B4 is too big, needs in time spacing when long roof beam 7 reaches stress limit, avoids making long roof beam 7 fracture, and the length in horizontal bar hole is also difficult for the undersize, and the undersize can't realize the effect of the structure vibration amplitude of decay in a plurality of frequency ranges, plays the damping and the meaning that slides and set up.
The fifth concrete implementation mode: the present embodiment is described with reference to fig. 1, and the present embodiment is further limited to the vibrator described in the second embodiment, and in the present embodiment, the vibrator includes a cylindrical rubber 5 and a cylindrical steel block 6, one end of the cylindrical rubber 5 is fixedly connected to one end of the cylindrical steel block 6, and the other end of the cylindrical rubber 5 is fixedly connected to the lower surface of the long beam 7. Other components and connection modes are the same as those of the first embodiment.
So set up, the additional oscillator can be at the vibration of certain frequency range decay long roof beam on long roof beam 7, and the oscillator comprises cylinder type rubber 5 and cylinder type steel bloom 6, and the amplitude of long roof beam 7 when the atress is mainly absorbed to cylinder type rubber 5, reaches the effect of buffering, and cylinder type steel bloom 6 is used for the counter weight.
The sixth specific implementation mode: the present embodiment is described with reference to fig. 1, and the present embodiment further defines the cylindrical rubber 5 according to the second embodiment, and in the present embodiment, the diameter of the end surface of the cylindrical rubber 5 is smaller than the diameter of the end surface of the cylindrical steel block 6. Other components and connection modes are the same as those of the first embodiment.
The seventh embodiment: the present embodiment is described with reference to fig. 1, and the present embodiment further defines the number of the flexible supporting members described in the second embodiment, and in the present embodiment, the number M of the flexible supporting members ranges from 2 to 4. Other components and connection modes are the same as those of the first embodiment.
The specific implementation mode is eight: the present embodiment is described with reference to fig. 1, and the present embodiment further defines the distance between the fixed support assembly described in the second embodiment and the adjacent flexible support assembly, in the present embodiment, the distance between the fixed support assembly and the adjacent flexible support assembly is L1, and the value range of L1 is 18-24 cm. Other components and connection modes are the same as those of the first embodiment.
So set up, fixed supporting component is difficult too big apart from between rather than the adjacent flexible supporting component, influences long roof beam 7 decomposition and transmission of atress when too big, and the damping effect is poor, also is difficult for the undersize, and the undersize can lead to long roof beam 7 local atress too big, leads to the fracture easily.
The specific implementation method nine: the present embodiment is described with reference to fig. 1, and the present embodiment further defines the distance between two adjacent flexible supporting assemblies described in the second embodiment, in the present embodiment, the distance between two adjacent flexible supporting assemblies is L2, and the value range of L2 is 18-24 cm. Other components and connection modes are the same as those of the first embodiment.
So set up, should not too big apart from between two adjacent flexible supporting component, influence long roof beam 7 decomposition and transmission of atress when too big, the damping effect is poor, also is difficult for the undersize, and the undersize can lead to long roof beam 7 local atress too big, leads to the fracture easily.
The detailed implementation mode is ten: the present embodiment is described with reference to fig. 1, and the present embodiment further defines the pitch between two adjacent oscillators described in the second embodiment, and in the present embodiment, the pitch between two adjacent oscillators is L3, and the value range of L3 is 18 to 24 cm. Other components and connection modes are the same as those of the first embodiment.
Comparing the wide-frequency-band vibration-damping noise-reducing metamaterial multi-span beam structure designed according to the above specific embodiment with the existing beam structure, and explaining the curves of vibration frequency and displacement of the long beam under the stress condition with reference to fig. 5 and 6, fig. 5 is the curve of vibration frequency and displacement of the structure in the patent, the abscissa is frequency (unit Hz), and the ordinate is displacement (m) of beam vibration, and it can be clearly seen from the graph that the three frequency ranges of 26-101Hz, 160-236Hz, 306-489Hz are called band gaps, 160-236Hz is a relatively sharp local resonance band gap, and the other two band gaps are called Bragg band gaps, and the vibration displacement of the beam is very small in the three frequency ranges, so that the vibration-damping effect can be achieved in the three frequency ranges. The three band gaps appear in relation to the design of the structure, fig. 6 is a curve of vibration frequency and displacement of a common beam, and no band gap exists in comparison with fig. 5 after any design, so that the new structure designed in the patent can play a role in vibration reduction and noise reduction in multiple frequency ranges.