CN119649783A - A gradient design engineering shock tube vibration and noise reduction device - Google Patents
A gradient design engineering shock tube vibration and noise reduction device Download PDFInfo
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- CN119649783A CN119649783A CN202411652543.1A CN202411652543A CN119649783A CN 119649783 A CN119649783 A CN 119649783A CN 202411652543 A CN202411652543 A CN 202411652543A CN 119649783 A CN119649783 A CN 119649783A
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Abstract
本发明涉及工程抗爆行业中激波管试验装置的减振降噪技术领域，具体是一种梯度设计式工程用激波管减振降噪装置。包括激波管、喷注消声模块、减振降噪模块；所述激波管与所述喷注消声模块相连；所述减振降噪模块与所述喷注消声模块相连；所述激波管与所述喷注消声模块与所述减振降噪模块为同轴布置。本发明提供的梯度设计式工程用激波管减振降噪装置，利用梯度设计优化气流和声波传播路径，从而有效降低激波管在工作过程中产生的噪声和振动，同时保持激波管的气动性能和运行效率。由周期性排列功能单元构成的减振降噪模块形成声学黑洞结构，相较于传统方法有更好的声学和弹性波操控物理特性，可以有效降低激波的传播速度,减小边界末端的反射。
The present invention relates to the technical field of vibration reduction and noise reduction of shock tube test equipment in the engineering explosion-proof industry, and specifically to a gradient-designed vibration reduction and noise reduction device for shock tubes used in engineering. It includes a shock tube, an injection silencer module, and a vibration reduction and noise reduction module; the shock tube is connected to the injection silencer module; the vibration reduction and noise reduction module is connected to the injection silencer module; the shock tube and the injection silencer module are coaxially arranged with the vibration reduction and noise reduction module. The gradient-designed vibration reduction and noise reduction device for shock tubes used in engineering provided by the present invention optimizes the airflow and sound wave propagation path by gradient design, thereby effectively reducing the noise and vibration generated by the shock tube during operation, while maintaining the aerodynamic performance and operating efficiency of the shock tube. The vibration reduction and noise reduction module composed of periodically arranged functional units forms an acoustic black hole structure, which has better acoustic and elastic wave manipulation physical properties than traditional methods, and can effectively reduce the propagation speed of the shock wave and reduce the reflection at the boundary end.
Description
Technical Field
The invention relates to the technical field of vibration and noise reduction of shock tube test devices in engineering antiknock industry, in particular to a shock tube vibration and noise reduction device for gradient design engineering.
Background
In modern engineering application, the shock tube is used as a high-efficiency aerodynamic device, and is widely applied to the fields of aerospace, national defense, automobiles and the like and used for simulating phenomena such as high-speed airflow, explosion fluctuation and the like. However, since shock tubes generate intense sound waves and shock waves during operation, these sound waves and shock waves not only interfere with the proper operation of the device, but may also produce significant noise pollution to the surrounding environment. Therefore, how to effectively reduce vibration and noise is an important issue in the research of shock tube technology. In the prior art, although several methods for vibration damping and noise reduction have been proposed, such as adding a sound absorbing material in the shock tube, adopting a complex sound insulation structure, etc., these methods generally have problems of low efficiency, large volume, high cost, or negative influence on the performance of the shock tube. For example, conventional sound absorbing materials often cannot operate stably for a long period of time in high temperature, high pressure environments, resulting in deterioration of vibration damping effects. In addition, the complex sound insulation structure not only increases the volume and weight of the device, but also can influence the pneumatic performance of the shock tube, and reduces the service efficiency of the shock tube. In recent years, researchers have attempted to improve vibration and noise reduction performance by improving the flow structure and materials inside the shock tube. For example, there has been some progress in controlling the propagation paths of sound waves and laser waves by introducing techniques such as porous media, flow control devices, and the like. However, these techniques are complex to implement, are difficult to operate, and have limitations in terms of adaptability and effectiveness to noise fluctuations of different frequencies and intensities.
How to effectively reduce noise and improve vibration characteristics while maintaining performance and operational simplicity of shock tubes is a problem to be solved in the current technical field.
Disclosure of Invention
The shock tube vibration and noise reduction device for the gradient design type engineering is capable of reducing vibration and noise of the shock tube for the engineering under the explosion of compressed air, can be used for controlling vibration and noise of a large-scale indoor shock tube test, is high in operability, simple in test parameter regulation and control method of vibration and noise frequency, amplitude, action direction and the like caused by different high-speed shock waves in the test, has a wide application range, is formed by connecting a shock tube for the traditional engineering, an injection silencing device and a simple vibration and noise reduction device, is low in manufacturing cost, has good economic benefit, and is detachable in all parts, and test pieces are easy and convenient to install and replace.
The invention adopts the following technical scheme:
the shock tube vibration and noise reduction device for gradient design type engineering comprises a shock tube, an injection noise elimination module and a vibration and noise reduction module, wherein the shock tube is connected with the injection noise elimination module, the vibration and noise reduction module is connected with the injection noise elimination module, and the shock tube, the injection noise elimination module and the vibration and noise reduction module are coaxially arranged.
The shock tube vibration and noise reduction device for the gradient design type engineering comprises a tube body, wherein flanges are arranged at two ends of the tube body, a plurality of cylindrical perforated exhaust columns are arranged on the tube body, a plurality of supporting rib plates are arranged between the flanges at two ends of the tube body, and the supporting rib plates are parallel to each other.
The shock tube vibration and noise reduction device for the gradient design type engineering comprises a plurality of cylindrical perforated air exhaust columns, wherein the cylindrical perforated air exhaust columns are distributed along the circumferential surface of a tube body in a spacing mode, a plurality of continuously-through frustum-shaped holes are formed in the cylindrical perforated air exhaust columns, large diameter openings of the frustum-shaped holes face the outer side of the tube body in sequence, and a supporting rib plate is arranged between every two adjacent cylindrical perforated air exhaust columns.
The shock tube vibration and noise reduction device for gradient design type engineering comprises a tube, wherein an annular wave baffle device is arranged in the tube, the annular wave baffle device consists of a plurality of annular wave baffles, a noise reduction hole is formed in the center of each annular wave baffle, and the inner radius of each noise reduction hole in each annular wave baffle device is changed according to a power law function to realize acoustic impedance adjustment.
The shock tube vibration and noise reduction device for the gradient design type engineering further comprises a rigid support ring, wherein the rigid support ring is arranged between every two adjacent annular wave baffles in the annular wave baffle device, and the rigid support ring is mutually fixed with the annular wave baffles and the tube barrel in the annular wave baffle device by welding.
The shock tube vibration and noise reduction device for gradient design type engineering provided by the invention has the advantages that the inner diameters of the noise reduction holes of the plurality of annular wave baffle devices are gradually decreased from large to small along the axial direction of the tube barrel, and then gradually increased from small to large.
The invention relates to a shock tube vibration and noise reduction device for gradient design engineering, wherein the inner radius of a noise reduction hole follows the expression of power law function change as follows:
ri＝εxm+r0
where r 0 is a constant, ε is the first power law constant, m is the power law exponent, and x is the distance of the ring from the center point.
The large diameter of the frustum-shaped hole in the cylindrical perforated exhaust column is smaller than the inner diameter of the cylindrical perforated exhaust column.
The shock tube vibration and noise reduction device for gradient design type engineering is characterized in that the cylindrical perforated exhaust column is made of high-strength steel, and the major diameter of the frustum-shaped hole is 2/3 of that of the cylindrical perforated exhaust column.
The invention has the beneficial effects that:
1. The shock tube vibration and noise reduction device for gradient design engineering provided by the invention optimizes the airflow and acoustic wave propagation paths by utilizing gradient design, thereby effectively reducing noise and vibration generated by the shock tube in the working process, and simultaneously maintaining the pneumatic performance and the operation efficiency of the shock tube, and compared with the traditional method, the shock tube vibration and noise reduction device for gradient design engineering has better acoustic and elastic wave control physical characteristics, and can effectively reduce the propagation speed of laser waves and reduce the reflection at the tail end of a boundary.
2. The shock tube vibration and noise reduction device for gradient design engineering provided by the invention has the advantages that the injection silencing module is provided with the function of eliminating wave bands and reducing the peak pressure of shock waves, so that the shock waves are reduced to be within a safe range, and the airflow is inhibited from forming a bypass phenomenon at a pipe orifice.
3. According to the shock tube vibration and noise reduction device for gradient design type engineering, provided by the invention, the space between the annular wave baffle devices of the vibration and noise reduction module is linearly changed, the slow sound effect of the acoustic black hole is reserved, the gradient change of the inner radius of the annular wave baffle devices is equivalent to a detuned absorber, the generated broadband low-frequency acoustic band gap and elastic band gap can effectively reduce the noise of the shock tube and inhibit the vibration of a structure, meanwhile, the pneumatic performance and the operation efficiency of the shock tube are maintained, and the operability is strong.
4. The shock tube vibration and noise reduction device for gradient design engineering provided by the invention has the advantages that the method for regulating and controlling test parameters such as vibration and noise frequency, amplitude, action direction and the like caused by different high-speed shock waves in a test is simple, and the shock tube vibration and noise reduction device has a wide application range.
5. The shock tube vibration and noise reduction device for the gradient design type engineering provided by the invention is formed by connecting a shock tube, an injection noise elimination device and a simple vibration and noise reduction device for the traditional engineering, has low cost and good economic benefit, and is simple and convenient to install and replace test pieces, and all parts are detachable.
Drawings
The invention is further described below with reference to the accompanying drawings.
FIG. 1 is a front view of the device of the present invention;
FIG. 2 is a schematic cross-sectional view of the overall structure of the device of the present invention;
FIG. 3 is a schematic perspective view of the overall structure of the device of the present invention;
FIG. 4 is a schematic view of a cylindrical perforated exhaust column in an injection muffling module of the present invention;
FIG. 5 is a schematic view of an internal cross-section of the vibration and noise reduction module structure of the present invention;
Fig. 6 is a schematic view of the overall structure of the injection muffling module of the present invention.
In the figure, the shock tube comprises a 1-shock tube, a 2-flange I, a 3-left end flange, a 4-cylindrical perforated exhaust column, a 5-supporting rib plate, a 6-injection noise elimination module, a 7-right end flange, a 8-flange II, a 9-test piece to be tested, a 10-tube barrel, an 11-annular wave baffle device, a 12-rigid supporting ring and a 13-frustum-shaped hole.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
In order that the above-recited objects, features and advantages of the present invention will become more readily apparent, a more particular description of the invention will be rendered by reference to the appended drawings and appended detailed description.
Referring to fig. 1 to 6, the invention discloses a shock tube vibration and noise reduction device for gradient design type engineering, which comprises a shock tube 1, an injection noise elimination module 6 and a vibration and noise reduction module 10.
The shock tube comprises a tube body 1 and a flange I2 at one end, wherein the flange I2 is coaxially and fixedly connected to the outer side of the shock tube 1 through welding.
The injection silencing module comprises a plurality of cylindrical perforated exhaust columns 4 on the pipe wall of the injection silencing module, and the cylindrical perforated exhaust columns 4 are welded with the pipe body of the injection silencing module 6.
The two ends of the pipe body of the injection silencing module 6 are respectively preset with a left end flange 3 and a right end flange 7 with high-strength bolt holes, one end of the injection silencing module 6 is coaxially fixedly connected with the left end flange 3, the other end of the injection silencing module 6 is coaxially fixedly connected with the right end flange 7, and a plurality of supporting rib plates 5 are uniformly distributed between the left end flange 3 and the right end flange 7 along the injection silencing module 6 in a ring mode.
The support rib plates 5 and the cylindrical perforated exhaust columns are uniformly distributed along the pipe body of the injection silencing module 6 in a spacing mode, the support rib plates 5 are welded with the left end flange 3 and the right end flange 7, the support rib plates 5 are welded with the pipe body of the injection silencing module 6, the flange 2 is connected with the left end flange 3 of the pipe body of the injection silencing module 6 through high-strength bolts, and bolt cushion layers are arranged between the high-strength bolts.
The pipe body of the injection noise elimination module 6 is consistent with the pipe barrel 10 of the vibration reduction noise reduction module in radius, and the test piece 9 to be tested is clamped between the pipe body and the pipe barrel.
The vibration and noise reduction module comprises a plurality of annular wave baffle devices 11 with inner radius changing in a pipe body of the vibration and noise reduction module, the annular wave baffle devices 11 are connected with the pipe body of the vibration and noise reduction module in a welding mode, the inner radius of each annular wave baffle device 11 changes according to a power law function to achieve acoustic impedance adjustment, rigid support rings 12 are arranged between the annular wave baffle devices 11 at intervals, the rigid support rings 12 are welded with the pipe body of the vibration and noise reduction module, and one end of the vibration and noise reduction module is coaxially fixedly connected with a second flange 8.
The left end flange 3 of the injection silencing module 6 is connected with the flange one 2 of the shock tube 1 through a coaxial high-strength bolt, and the right end flange 7 of the injection silencing module 6 is connected with the flange two 8 of the vibration reduction and noise reduction module through a coaxial high-strength bolt.
The right end flange 7 is connected with a flange II 8 of the vibration and noise reduction module through a high-strength bolt, and a bolt cushion layer is arranged between the high-strength bolt and the high-strength bolt hole.
The pipe wall of the injection silencing module 6 is provided with 8 cylindrical perforated air discharging columns 4, the cylindrical perforated air discharging columns 4 are welded with the pipe body of the injection silencing module 6, a plurality of continuously-through frustum-shaped holes 13 are arranged in the cylindrical perforated air discharging columns 4, the large diameter openings of the frustum-shaped holes 13 face the outer side of the pipe body in sequence, and the frustum-shaped holes 13 are coaxial with the cylindrical perforated air discharging columns 4.
The test piece 9 to be tested is clamped between the right end flange 7 of the injection noise elimination module 6 and the second flange 8 of the left end of the vibration and noise reduction module, the right end flange 7, the second flange 8 of the left end of the vibration and noise reduction module and the test piece 9 to be tested are tightly connected through high-strength bolts, and rubber thin cushion layers are contained between the layers.
When the shock wave tube is used, the high-pressure shock wave generated by the shock wave tube 1 is used for shock testing the test piece 9 to be tested, the shock wave after breaking and decelerating the test piece 9 to be tested passes through the cylindrical perforated exhaust column 4 of the jet-grouting noise elimination module 6, the shock wave can be quickly weakened, when the decelerated shock wave passes through the vibration reduction and noise reduction module, the periodically arranged annular wave baffle devices 11 form an acoustic black hole structure and generate a slow sound effect, the inner radius gradient change of the annular wave baffle devices is subjected to detuning and vibration absorption to generate a broadband low-frequency acoustic band gap and an elastic band gap, the propagation speed of the shock wave is reduced, the reflection at the tail end of the boundary is reduced, the quick attenuation of the shock wave speed and the quick dispersion of energy can be realized, the reduction of large-range vibration and the increase of acoustic impedance are realized, and the vibration reduction and noise reduction performance improvement effects are further realized.
The distance between the annular wave baffle device 11 and the second flange 8 is determined by the safe distance of the splash fragments possibly generated after the stimulated wave impact of the test piece 9 to be tested. The method has the advantages that the fragment cloud outline of the main test piece material concrete and steel under the action of shock waves is obtained through shock tube test data, the whole flying form of the fragments can be intuitively described, and formula fitting is carried out. When the debris cloud has a certain initial speed, the influence of gravity on the profile shape is negligible, and the profile of the debris cloud is approximately centrosymmetric with respect to the axis. Through working condition statistics and least square fitting, the distance between the annular wave baffle device 11 and the flange II 8 can be confirmed to be more than 0.5 m. The length of the jet silencing module tube body 6 is approximately 0.5m to 1.0m of dominant wavelength of shock tubes, and the perforated exhaust column is arranged at a position corresponding to the midpoint of the axis of the jet silencing module tube body.
The inner radius of the annular wave blocking device 11 decreases according to the power law function, and the wave blocking devices are arranged equidistantly. This structure retains the slow sound effect of the acoustic black holes and the unevenly distributed rings act as tuned vibration absorbers, based on these characteristics, both the acoustic and elastic band gap for broadband low frequencies can be produced.
The inner radius of the annular wave blocking device changes along the power law function:
ri＝εxm+r0
where r 0 is a constant, ε is the first power law constant, m is the power law exponent, and x is the distance of the ring from the center point.
The slow sound effect of the acoustic black hole causes the wave velocity to gradually decrease along the tube body of the vibration and noise reduction module, so that the shock wave cannot reach the tail end of the structure and cannot be reflected. This effect corresponds to an extension of the shock wavelength. The propagation characteristics of shock waves in the vibration reduction and noise reduction module can be changed by adjusting the change gradient of the inner radius of the annular wave shield device, namely, the epsilon value and the m value.
Parametric analysis shows that as m increases, the acoustic bandgap shifts to the low frequency region because the acoustic black hole slow-sound effect increases. In addition, by adjusting the number n of rings, the separated narrow band gaps can be combined into a wider band gap, thereby improving the noise elimination and noise reduction effect. The propagation path and speed of the laser wave can be effectively adjusted by precisely controlling the change gradient of the inner radius of the annular wave shield device, and the acoustic band gap of the low-frequency broadband is realized, so that the purposes of noise elimination and noise reduction are achieved.
The annular wave blocking device 11 is arranged in the vibration reduction and noise reduction module, the inner radius of the annular wave blocking device is changed according to a power law function to realize acoustic impedance adjustment, an acoustic black hole is formed, the propagation speed of laser waves in the structure can be effectively reduced, reflection at the tail end of a boundary is reduced, and a region with high energy density is formed, so that the vibration reduction and noise reduction module has wide application prospects in the aspects of vibration reduction, noise reduction, fluctuation regulation, energy recovery and the like.
The distance between the rings changes linearly, the slow sound effect of the acoustic black holes is reserved, the unevenly distributed circular rings are used as detuning vibration absorbers, and meanwhile, a broadband low-frequency acoustic band gap and a flexible band gap are generated, so that airborne noise can be effectively reduced, and structural vibration can be restrained.
The vibration and noise reduction module formed by the periodically arranged functional units has better physical characteristics of acoustic and elastic wave control compared with the traditional method.
Band gap refers to the frequency band in which acoustic and elastic waves cannot be transmitted through a medium. By controlling the position and width of the band gap, the gradient design method shows outstanding advantages over the conventional methods in terms of low-frequency sound insulation and vibration.
The acoustic black hole structure can simultaneously generate acoustic and vibration band gaps for multifunctional design. In addition, the non-uniformly distributed circular rings in the acoustic black hole structure are equivalent to detuning absorbers, and the local resonance band gap is widened due to the detuning effect.
The 8 perforated exhaust columns 4 on the pipe wall of the injection silencing module 6 are arranged around the pipe wall, and the 8 supporting rib plates 5 are arranged around the pipe wall coaxially with the perforated exhaust columns 4, and the surrounding angle is offset by 11.25 degrees.
The perforated exhaust column 4 is made of high-strength steel, the bottom radius of the frustum-shaped hole is not easy to be larger than the radius of the 2/3 perforated exhaust column 4, and is not easy to be too small, and the perforated exhaust column has the advantages that the perforated exhaust column is simple and feasible in device, can realize rapid weakening of shock waves after the test piece 3 to be tested is broken through adjusting the hole radius, is suitable for high-pressure pipelines and variable load conditions, and is easy and convenient to replace.
The annular wave baffle device 11 with fixed period distance and gradient change of inner radius is arranged in the pipe barrel 10 of the vibration reduction and noise reduction module, and the propagation speed of laser waves is reduced by forming an acoustic black hole, so that the reflection of the tail end of the boundary is reduced, and the pneumatic noise is reduced, thereby realizing rapid vibration reduction and noise reduction. The size of the annular wave shield device 11 can be approximately confirmed according to the shock wavelength and the wave speed, the thickness of the tube 10 of the vibration and noise reduction module is not less than 2/3 times of the safety requirement, and the gradient of the change of the inner radius of the annular wave shield device 11 is preferably selected from 10% to 15%.
The foregoing has shown and described the basic principles, principal features and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and that the above embodiments and descriptions are merely illustrative of the principles of the present invention, and various changes and modifications may be made without departing from the spirit and scope of the invention, which is defined in the appended claims.
Claims (9)
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| CN202411652543.1A CN119649783A (en) | 2024-11-19 | 2024-11-19 | A gradient design engineering shock tube vibration and noise reduction device |
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| CN202411652543.1A CN119649783A (en) | 2024-11-19 | 2024-11-19 | A gradient design engineering shock tube vibration and noise reduction device |
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