A double-chamber Helmholtz resonator

Abstract

The present invention discloses a novel double-chamber Helmholtz resonator. The novel double-chamber Helmholtz resonator includes an intake pipe, the side wall of the intake pipe is communicated with a silencing pipe through two short pipes, the opening of the silencing pipe is at the break between the two short pipes, a base is arranged at the break, a slideway is opened on the base, a damping plate is inserted into the slideway, the damping plate divides the silencing pipe into a first resonance chamber and a second resonance chamber, a plurality of damping holes communicating the first resonance chamber and the second resonance chamber are opened on the damping plate, transverse holes are opened on both sides of the slideway, ejector pins are arranged in the transverse holes, a spherical convex surface is arranged at the front end of the ejector pin, a spherical concave surface matched with the spherical convex surface is opened on the damping plate, a shoulder platform is arranged at the tail end of the ejector pin, a hole step is arranged at the front end of the transverse hole, a plunger is arranged at the tail end of the transverse hole, a spring is arranged between the plunger and the shoulder platform, and the spring drives the spherical convex surface to extend out of the transverse hole. The present invention solves the problem that the frequency band broadened by the prior art still has certain limitations and cannot achieve the effect of precise noise reduction.

Description

Technical Field

[0001] The present invention relates to the technical field of ship combustion chambers, and particularly relates to a double-chamber Helmholtz resonator. Background Art

[0002] The Helmholtz resonator is widely used as a muffler to suppress the oscillation caused by combustion. The traditional Helmholtz resonator usually consists of a connecting neck and a resonance cavity. The fluid inside the resonance cavity can resonate at a certain frequency (also known as the resonance frequency). This process can convert sound energy into heat energy, which is ultimately dissipated by the working medium, thereby achieving the sound elimination effect.

[0003] In order to expand the effective frequency band, two or more Helmholtz resonators are usually combined for use. The existing "Helmholtz Resonator and Its Working Method" disclosed in the application number CN201910966633.0 eliminates the main noise by adjusting the aperture size of the aperture valve according to the pressure sensor, so as to achieve the best sound elimination effect. In this way, not only can the sound elimination frequency band be broadened, but also the resonance frequency can be adjusted within a certain range. However, the aperture valve has only one hole, and one extreme state of the hole is closed, and the other extreme state is fully open. The broadened frequency band still has certain limitations and cannot achieve the effect of precise noise reduction. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a double-chamber Helmholtz resonator that further broadens the frequency band range and achieves precise noise reduction.

[0005] To achieve the above purpose, the technical solution adopted by the double-chamber Helmholtz resonator of the present invention is as follows:

[0006] A double-chamber Helmholtz resonator includes an air inlet pipe. The side wall of the air inlet pipe is connected to a sound silencing pipe through two short pipes. The sound silencing pipe is provided with a break between the two short pipes. A base is arranged at the break. A slideway is arranged on the base. A damping plate is inserted into the slideway. The damping plate divides the sound silencing pipe into a first resonance cavity and a second resonance cavity. The damping plate is provided with a plurality of damping holes communicating the first resonance cavity and the second resonance cavity. Transverse holes are arranged on both sides of the slideway. A spring ejecting pin is arranged in the transverse holes. A spherical convex surface is arranged at the front end of the spring ejecting pin. A spherical concave surface matching the spherical convex surface is arranged on the damping plate. A shoulder platform is arranged at the tail end of the spring ejecting pin. A hole step for blocking the shoulder platform is arranged at the front end of the transverse hole. A plunger is arranged at the tail end of the transverse hole. A spring is arranged between the plunger and the shoulder platform. The spring drives the spherical convex surface to protrude out of the transverse hole.

[0007] Preferably, the base includes a first substrate and a second substrate installed at the fracture. The first substrate is detachably connected to the second substrate through a bolt assembly. A chute is formed on the surface of the first substrate that fits the second substrate. The inner wall of the chute and the end face of the second substrate form a slideway for inserting the damping plate.

[0008] Preferably, a first sealing ring is arranged between the first substrate and the damping plate, and a second sealing ring is arranged between the second substrate and the damping plate.

[0009] Preferably, the first substrate is installed at one end of the fracture through a first flange, and the second substrate is installed at the other end of the fracture through a second flange.

[0010] Preferably, a third sealing ring is arranged between the first substrate and the first flange, and a fourth sealing ring is arranged between the second substrate and the second flange.

[0011] Preferably, the cross-section of the damping hole can be a regular geometric figure or an irregular figure.

[0012] Preferably, a lifting hole is formed at one end of the damping plate that extends out of the slideway.

[0013] Compared with the prior art, the present invention has the following advantages:

[0014] By collecting the noise frequency through the sound pressure sensor, different damping plates are selected. The differences between the damping plates lie in the number of through holes, the shape of the through holes, and the size. In this way, the frequency band range can be further broadened to achieve precise noise reduction. When the damping plate is inserted into the slideway, the spherical convex surface sinks into the spherical concave surface, which can not only ensure that the damping plate is inserted in place but also prevent the damping plate from sliding freely on the slideway. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a cross-sectional view of the double-chamber Helmholtz resonator of the present invention;

[0016] Figure 2 is Figure 1 an enlarged view of part A of

[0017] Figure 3 is a schematic structural diagram of the double-chamber Helmholtz resonator of the present invention;

[0018] Figure 4 is an exploded view of the structure of the double-chamber Helmholtz resonator of the present invention;

[0019] Figure 5 is a schematic structural diagram of the damping plate;

[0020] Figure 6 is a cross-sectional view of the first substrate;

[0021] Figure 7 isFigure 6 Enlarged view at position B;

[0022] Figure 8 It is a schematic structural view of a spring-loaded pin;

[0023] Figure 9 It is a cross-sectional view of the second substrate.

[0024] Wherein, 1 is an air inlet pipe, 2 is a short pipe, 3 is a silencing pipe, 31 is a fracture, 32 is a first flange, 33 is a second flange, 34 is a first resonance cavity, 35 is a second resonance cavity, 4 is a base, 41 is a first substrate, 411 is a sliding groove, 412 is a transverse hole, 4121 is a hole step, 413 is a spring-loaded pin, 4131 is a spherical convex surface, 4132 is a shoulder, 414 is a plunger, 415 is a spring, 416 is a first annular groove, 417 is a third annular groove, 42 is a second substrate, 421 is a second annular groove, 422 is a fourth annular groove, 43 is a slideway, 5 is a damping plate, 51 is a spherical concave surface, 52 is a damping hole, 53 is a lifting hole, 6 is a first sealing ring, 7 is a second sealing ring, 8 is a third sealing ring, 9 is a fourth sealing ring. Specific embodiments

[0025] The present invention will be further clarified below in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. After reading the present invention, those skilled in the art's various equivalent forms of modification of the present invention all fall within the scope defined by the appended claims of this application.

[0026] Such as Figures 1-9As shown in the figure, a double-chamber Helmholtz resonator includes an intake pipe 1. The side wall of the intake pipe is connected to a silencing pipe 3 through two short pipes 2. A break 31 is opened in the middle of the silencing pipe. The break is located between the two short pipes. A first flange 32 is welded to the left end of the break, and a second flange 33 is welded to the right end of the break. A base 4 is installed between the first and second flanges. The base includes a first substrate 41 and a second substrate 42. The first substrate is detachably connected to the second substrate through a bolt assembly. A chute 411 is opened on the surface of the right side of the first substrate that fits with the second substrate. The inner wall of the chute and the left end face of the second substrate form a slideway 43 for inserting a damping plate 5. Transverse holes 412 are opened on both sides of the slideway. A spring-loaded pin 413 is placed in the transverse hole. A spherical convex surface 4131 is machined at the front end of the spring-loaded pin. A spherical concave surface 51 that cooperates with the spherical convex surface is opened on the damping plate. A shoulder 4132 is integrally formed at the tail end of the spring-loaded pin. A hole step 4121 that blocks the shoulder is machined at the front end of the transverse hole. A plunger 414 is threadedly connected to the tail end of the transverse hole. A spring 415 is placed between the plunger and the shoulder. The spring drives the spherical convex surface to extend out of the transverse hole and sink into the spherical concave surface of the damping plate. The damping plate divides the silencing pipe into a first resonance cavity 34 and a second resonance cavity 35. A number of damping holes 52 that connect the first resonance cavity and the second resonance cavity are opened on the damping plate. The cross-section of the damping hole can be a regular geometric figure or an irregular figure. A lifting hole 53 is opened at one end of the damping plate that extends out of the slideway, which is convenient for extracting and replacing the damping plate. A first sealing ring 6 is arranged between the first substrate and the damping plate. The first substrate is provided with a first annular groove 416 for accommodating the first sealing ring. A second sealing ring 7 is arranged between the second substrate and the damping plate. The second substrate is provided with a second annular groove 421 for accommodating the second sealing ring. The first substrate is detachably connected to the first flange through bolts. A third sealing ring 8 is arranged between the first substrate and the first flange. The first substrate is provided with a third annular groove 417 for accommodating the third sealing ring. The second substrate is detachably connected to the second flange through bolts. A fourth sealing ring 9 is arranged between the second substrate and the second flange. The second substrate is provided with a fourth annular groove 422 for accommodating the fourth sealing ring.

[0027] Specific working process and principle of the present invention: By collecting the noise frequency through a sound pressure sensor, different damping plates are selected. The differences in the damping plates lie in the number of through holes, the shape of the through holes, and the size. This can further broaden the frequency band range and achieve precise noise reduction. The damping plate is inserted into the slideway. The chamfered surface at the lower part of the damping plate drives the spring ejector pin to retract until the spherical convex surface sinks into the spherical concave surface, indicating that the damping plate is inserted in place. At the same time, the damping plate is placed to slide freely on the slideway. When the incident sound wave travels from left to right in the intake pipe, the sound wave enters the first resonance cavity from the left short pipe, causing the air in the left short pipe to move back and forth to compress the air in the first resonance cavity, forming an air spring. This process can convert sound energy into heat energy. When the incident sound wave passes through the damping hole, due to the friction with the edge, a vortex flow will be formed, converting the sound energy into kinetic energy and entering the second resonance cavity. Similarly, the air in the second resonance cavity moves back and forth, finally dissipating the sound energy. A small part of the sound wave that is not dissipated returns to the intake pipe through the right short pipe. The present invention selects a damping plate according to the frequency of the incident sound wave. The number of holes and the through-hole rate on the damping plate determine the natural frequency of the resonator structure. When the frequency of the incident sound wave is consistent with the natural frequency of the resonator structure, the resonance amplitude is the largest, the energy consumed is the most, and the best sound absorption effect is achieved.

Claims

1. A double-chamber Helmholtz resonator, comprising an intake pipe, the side wall of the intake pipe is communicated with a silencing pipe through two short pipes, the silencing pipe is provided with a break located between the two short pipes, and it is characterized in that: A base is provided at the fracture. A slideway is formed on the base. A damping plate is inserted into the slideway. The damping plate divides the silencing pipe into a first resonance cavity and a second resonance cavity. A number of damping holes communicating the first resonance cavity and the second resonance cavity are formed on the damping plate. Transverse holes are formed on both sides of the slideway. A spring ejector pin is arranged in the transverse holes. A spherical convex surface is arranged at the front end of the spring ejector pin. A spherical concave surface matching the spherical convex surface is formed on the damping plate. A shoulder is arranged at the tail end of the spring ejector pin. A hole step for blocking the shoulder is arranged at the front end of the transverse hole. A plunger is arranged at the tail end of the transverse hole. A spring is arranged between the plunger and the shoulder. The spring drives the spherical convex surface to extend out of the transverse hole. The base includes a first substrate and a second substrate installed at the fracture. The first substrate is detachably connected to the second substrate through a bolt assembly. A chute is formed on the surface of the first substrate that fits with the second substrate. The inner wall of the chute and the end face of the second substrate form the slideway for inserting the damping plate. A first sealing ring is arranged between the first substrate and the damping plate. A second sealing ring is arranged between the second substrate and the damping plate. The first substrate is installed at one end of the fracture through a first flange. The second substrate is installed at the other end of the fracture through a second flange. A third sealing ring is arranged between the first substrate and the first flange. A fourth sealing ring is arranged between the second substrate and the second flange.

2. The dual-chamber Helmholtz resonator according to claim 1, wherein: The cross-section of the damping hole can be a regular geometric figure or an irregular figure.

3. The double-chamber Helmholtz resonator according to claim 1, characterized in that: A lifting hole is formed at one end of the damping plate extending out of the slideway.

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