CN110017282B

CN110017282B - Airflow pulsation attenuation device and air compressor

Info

Publication number: CN110017282B
Application number: CN201910363144.6A
Authority: CN
Inventors: 陈文卿; 周明龙; 何志龙; 邢子文
Original assignee: XI'AN JIAOTONG UNIVERSITY SUZHOU ACADEMY
Current assignee: XI'AN JIAOTONG UNIVERSITY SUZHOU ACADEMY
Priority date: 2019-04-30
Filing date: 2019-04-30
Publication date: 2020-11-06
Anticipated expiration: 2039-04-30
Also published as: CN110017282A

Abstract

The utility model discloses an air current pulsation damping device and air compressor, it sets up inside air compressor, the inside enclosure space that is provided with of air compressor, including high-pressure exhaust tip, splint at least one apron, the high-pressure exhaust tip splint with form at least one air current pulsation damping chamber between at least one apron be equipped with at least one damping channel on the apron, damping channel will air current pulsation damping chamber with the enclosure space is linked together. The embodiment of the disclosure can attenuate the air pulsation in the closed volume of the compressor by utilizing the friction action of the damping channel and the buffering action of the air pulsation attenuation cavity.

Description

Airflow pulsation attenuation device and air compressor

Technical Field

The present disclosure relates to the field of air flow processing technology, and in particular, to an air flow pulsation damping device and an air compressor.

Background

The compressor is used as general equipment for improving gas pressure and conveying gas, and is widely applied to the industrial fields of petroleum, natural gas, chemical industry, metallurgy and the like. The screw compressor is a rotary displacement compressor, and the female rotor and the male rotor are driven by a motor to be meshed with each other to form the volume change of a working cavity, so that the periodic working processes of air suction, compression and exhaust of the screw compressor are realized.

The gas pulsation is generated along with the periodic fluctuation of the gas pressure and the gas flow in the suction and exhaust processes of the screw compressor. In the compression process, the pressure is gradually increased along with the reduction of the closed volume, and the airflow pulsation is gradually increased; when compression is completed, the enclosed volume is the smallest, the fluid pressure is the largest, and the airflow pulsation increases sharply, which is the main excitation source for inducing vibration noise.

Disclosure of Invention

In view of the above problems in the prior art, the present disclosure is directed to solve the problem of the pulsation of the air flow occurring in the compression process of the compressor, and provides an air flow pulsation damping device for the compression process of the compressor, which is capable of damping the pulsation of the air flow occurring in the compression process of the compressor from the structural design, and further reducing the pulsation of the air flow occurring in the exhaust process, thereby suppressing the vibration noise induced by the pulsation of the air flow of the compressor.

In order to achieve the above object, one aspect of the present disclosure provides an airflow pulsation damping device, which is disposed inside an air compressor, wherein a closed space is disposed inside the air compressor, and the air compressor includes a high-pressure exhaust end portion and at least one cover plate, at least one airflow pulsation damping cavity is formed between the high-pressure exhaust end portion, the cover plate and the at least one cover plate, and at least one damping channel is disposed on the cover plate and communicates the airflow pulsation damping cavity with the closed space.

In some embodiments, the clamp plate is integrated on the high pressure exhaust end.

In some embodiments, the high pressure exhaust end, the clamping plate and the cover plate are connected by screws.

In some embodiments, the shape of the cover plate is at least one of circular, kidney-shaped, rectangular, triangular, fan-shaped, and arc-shaped.

In some embodiments, an aperture is provided in the cover plate to form the damping channel.

In some embodiments, the cross-sectional shape of the damping channel is at least one of circular, rectangular, triangular, elliptical, and arcuate.

In some embodiments, the cross-sectional shape of the damping channel can be tapered along the length.

In order to achieve the above object, another aspect of the present disclosure provides an air compressor including the airflow pulsation damping device in any one of the above technical solutions.

In order to achieve the above object, a further aspect of the present disclosure provides a screw compressor including the airflow pulsation damping device in any one of the above technical solutions. .

In some embodiments, the screw compressor includes a housing having intermeshing female and male rotors disposed therein, the housing, the female and male rotors forming an enclosed space therebetween.

Compared with the prior art, the airflow pulsation attenuation device for the air compressor compression process provided by the disclosure fully considers the problem of the installation space of equipment based on the working principle of the air compressor and the airflow pulsation generation mechanism, and according to the basic principle of the Helmholtz resonant cavity, high-pressure gas in the closed space of the air compressor enters the airflow pulsation attenuation cavity through the damping channel on the cover plate, and airflow pulsation in the closed volume of the compressor is attenuated by utilizing the friction effect of the damping channel and the buffering effect of the airflow pulsation attenuation cavity.

In addition, the airflow pulsation damping device provided by the disclosure further optimizes the cavity volume of the airflow pulsation damping cavity and the opening runner of the damping channel on the cover plate, so that the resonance frequency of the airflow pulsation damping device is consistent with the frequency of the airflow pulsation excitation source of the air compressor in the compression process, the purpose of damping the airflow pulsation in the compression process is achieved, and further the airflow pulsation in the exhaust process is reduced.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

This document provides an overview of various implementations or examples of the technology described in this disclosure, and is not a comprehensive disclosure of the full scope or all features of the disclosed technology.

Drawings

In the drawings, which are not necessarily drawn to scale, like reference numerals may describe similar components in different views. Like reference numerals having letter suffixes or different letter suffixes may represent different instances of similar components. The drawings illustrate various embodiments generally by way of example and not by way of limitation, and together with the description and claims serve to explain the disclosed embodiments. The same reference numbers will be used throughout the drawings to refer to the same or like parts, where appropriate. Such embodiments are illustrative, and are not intended to be exhaustive or exclusive embodiments of the present apparatus or method.

FIG. 1 is a schematic view of an airflow pulsation damping apparatus according to the present disclosure;

FIG. 2 is a schematic view of an airflow pulsation damping apparatus according to the present disclosure;

FIG. 3 is a cross-sectional view of an airflow pulsation dampener in accordance with the present disclosure;

FIG. 4 is a schematic diagram of a Helmholtz resonant cavity according to the present disclosure;

fig. 5 is a schematic diagram illustrating noise reduction effect using two resonant cavities according to the present disclosure.

Reference numerals:

11-high pressure exhaust end; 12-a splint; 13-a cover plate; 14-a screw; 15-a second cover plate; 21-a housing; 22-female rotor; 23-male rotor; 31-an enclosed space; 32-an airflow pulsation attenuation chamber; 33-a damping channel; 34-a second pneumatic pulsation damping chamber; 35-second damping channel.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present disclosure more clear, the technical solutions of the embodiments of the present disclosure will be described below clearly and completely with reference to the accompanying drawings of the embodiments of the present disclosure. It is to be understood that the described embodiments are only a few embodiments of the present disclosure, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the described embodiments of the disclosure without any inventive step, are within the scope of protection of the disclosure.

Unless otherwise defined, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs. The use of "first," "second," and similar terms in this disclosure is not intended to indicate any order, quantity, or importance, but rather is used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.

To maintain the following description of the embodiments of the present disclosure clear and concise, a detailed description of known functions and known components have been omitted from the present disclosure.

The disclosed embodiments relate to a gas pulsation attenuation apparatus, which may be used in a compression process of various types of compressors, such as a positive displacement compressor, a screw compressor, a roots compressor, a rotor compressor, and the like. In the present embodiment, the airflow pulsation damping device according to the present disclosure is disposed inside the screw compressor to reduce the airflow pulsation inside the screw compressor during the compression process.

As shown in fig. 1 to 3, fig. 1 and 2 show a schematic structural view of a screw compressor 1 and an airflow pulsation damping device, and fig. 3 shows a sectional structural view of the screw compressor 1 and the airflow pulsation damping device. The screw compressor 1 comprises a housing 21, a female rotor 22 and a male rotor 23 which are engaged with each other are arranged inside the housing 21, and a closed space 31 is formed among the housing 21, the female rotor 22 and the male rotor 23 during the operation of the screw compressor 1.

The screw compressor 1 is a rotary displacement compressor, and the motor inside the casing 21 drives the female rotor 22 and the male rotor 23 to mesh with each other to form a volume change of the closed space 31, so as to realize the periodic working processes of air suction, compression and air discharge of the screw compressor. The gas pressure and flow rate fluctuate periodically with the suction, compression and discharge processes of the screw compressor, thereby generating gas flow pulsations, for example, the pressure in the closed space 31 gradually rises and the gas flow pulsations gradually increase as the volume of the closed space 31 decreases during the compression process, which is also the main excitation source for inducing vibration noise.

The airflow pulsation damping device according to the present embodiment is disposed inside the screw compressor 1, for example, may be disposed inside a casing 21 of the screw compressor, and includes a high-pressure exhaust end 11, a clamping plate 12, and at least one cover plate 13, wherein at least one airflow pulsation damping chamber 32 is formed between the high-pressure exhaust end 11, the clamping plate 12, and the at least one cover plate 13, and each airflow pulsation damping chamber 32 is communicated with the enclosed space 31. It should be noted that if a plurality of cover plates 13 are provided, each cover plate 13 may form one airflow pulsation damping chamber 32 with the high pressure exhaust end 11 and the clamping plate 12 by the structural design of the high pressure exhaust end 11 and the clamping plate 12, so that a plurality of airflow pulsation damping chambers 32 may be formed, for example, in fig. 3, not only the cover plate 13 is provided to form the airflow pulsation damping chamber 32, but also the second cover plate 15 is provided to form the second pneumatic pulsation damping chamber 34. As an embodiment, the high pressure exhaust end 11, the clamping plate 12 and at least one cover plate 13 may be separate components, and as another embodiment, the clamping plate 12 may be integrated on the high pressure exhaust end 11, so that each air pulsation damping chamber 32 communicated with the closed space 31 is formed by the high pressure exhaust end 11 and the cover plate 13.

In the process of forming the at least one airflow pulsation damping chamber 32 by the high pressure exhaust end portion 11, the clamping plate 12 and the at least one cover plate 13, the high pressure exhaust end portion 11, the clamping plate 12 and the at least one cover plate 13 are connected and sealed by the screws 14, or may be connected and sealed by other methods such as welding, so long as the airflow pulsation damping chamber 32 is sealed.

Specifically, the shape of the cover plate 13 may be selected according to actual situations, and may be, for example, a circle, a kidney, a rectangle, a triangle, a sector, an arc, etc., and the specific shape is not limited herein. The number of the cover plates 13 may be selected according to the actual situation, and may be, for example, one or more.

At least one damping channel 33 is provided on the cover plate 13, the damping channel 33 being configured to communicate the airflow pulsation damping chamber 32 with the enclosed space 31. Specifically, an open-hole passage is provided on the cover plate 13 to form a damping passage 33 for passing the air flow in the closed space 31 to the airflow pulsation damping chamber 32. The damping channel 33 may also be formed in any other way, and the disclosure is not limited thereto.

Further, the cross-sectional shape of the damping channel 33 may be selected according to practical situations, and is not limited to circular, rectangular, triangular, elliptical, arc, etc. The cross-sectional shape of the damping channel 33 can also be tapered with length. In addition, the number of damping channels 33 on the cover plate 13 can also be selected according to the actual situation, and one or more damping channels 33 can be provided on each cover plate 13. That is, the airflow pulsation damping chamber 32 and the closed space 31 may communicate with each other through a plurality of damping passages 33, and the shape of each damping passage 33 may be selected and adjusted, particularly in the case where the airflow rate is large. For example, in fig. 3, a second damping channel 35 may be provided on the second cover plate 15.

By the technical solution of the embodiment of the present disclosure, the attenuation of the gas flow pulsation in the enclosed space 31 is based on the helmholtz resonator principle. The helmholtz resonator is mainly composed of a resonance chamber and short tubes, and in the present embodiment, the gas flow pulsation reducing chamber 32 and the damping passage 33 constitute the helmholtz resonator, wherein the gas flow pulsation reducing chamber 32 and the damping passage 33 correspond to the resonance chamber and the short tubes in the helmholtz resonator, respectively.

When the resonance frequency of the helmholtz resonator is close to the excitation frequency of the gas flow pulsation generated in the screw compressor 1, the gas flow pulsation in the screw compressor 1 resonates in the helmholtz resonator, and the fluid medium in the damping channel 33 strongly vibrates, thereby consuming energy by overcoming frictional resistance, attenuating the gas flow pulsation, and reducing the gas flow pulsation downstream of the helmholtz resonator. Wherein the content of the first and second substances,

the gas flow pulsation excitation frequency f in the compression chamber of the screw compressor 1 is:

wherein f is the airflow pulsation excitation frequency of the screw compressor 1, and the unit is Hz; z is the number of teeth of the male rotor of the screw compressor; n is the operating speed of the compressor, rpm.

As shown in fig. 4, the resonance frequency of the helmholtz resonator is:

wherein f is₀Is the resonance frequency of the helmholtz resonator, in Hz; c. C₀Is the speed of sound, m/s; l is the length of the damping channel 33 in m; d is the diameter of the damping channel 33 in m; s is the cross-sectional area of the damping channel 33 in m 2; v is the volume of the airflow pulsation damping chamber 32, and has the unit m 3.

It can be seen from the formula (1) that when the number of teeth of the male rotor of the screw compressor 1 and the operating speed are determined, the gas pulsation excitation frequency of the screw compressor is determined accordingly, and therefore, according to the formula (2), by means of changing the length L of the damping channel 33, the cross-sectional area of the damping channel 33, and the volume V of the gas pulsation attenuation cavity 32, the resonance frequency of the helmholtz resonant cavity and the gas pulsation excitation frequency of the screw compressor tend to be consistent, so that resonance is generated in the resonant cavity, and the purpose of attenuating the gas pulsation is achieved.

For the variable frequency screw compressor, because the operation rotation speed of the variable frequency screw compressor is constantly changed, the airflow pulsation excitation frequency in the screw compressor 1 is changed, so that the noise reduction frequency range can be widened by arranging a plurality of airflow pulsation attenuation cavities 32 in parallel, as shown in fig. 2, that is, for example, when a single resonant cavity is adopted, one resonant frequency is used for attenuating the airflow pulsation; when dual resonant cavities are present, there are two resonant frequencies to attenuate the gas flow pulsations.

Therefore, in combination with the present embodiment, by changing and adjusting the cavity volume of the airflow pulsation attenuation cavity 32 formed by the high-pressure exhaust end 11, the clamping plate 12 and the at least one cover plate 13 and the cross-sectional area of the damping channel 33 on each cover plate 13, the resonant frequency of the airflow pulsation attenuation device 1 is consistent with the frequency of the airflow pulsation excitation source of the screw compressor 1 during the compression process of the screw compressor, so as to achieve the purpose of attenuating the airflow pulsation in the closed volume 31, and further reduce the airflow pulsation in the exhaust cavity.

In addition, in another embodiment, without changing the cavity volume of the airflow pulsation damping cavity 32 formed by the high-pressure exhaust end 11, the clamping plate 12 and the cover plate 13, the sectional shape or the sectional area of the opening of the damping channel 33 on each cover plate 13 can be changed only, so that the resonant frequency of the airflow pulsation damping device is consistent with the frequency of the airflow pulsation excitation source of the screw compressor 1 during the compression process of the screw compressor 1, and the purpose of damping the airflow pulsation in the closed volume 31 can be achieved as well, thus, the high-pressure exhaust end 11 can be generalized, and only the cover plate 13 with different damping channels 33 can be replaced.

The airflow pulsation damping device according to the embodiment of the present disclosure can perform airflow pulsation damping in the following manner:

during operation of the screw compressor, as the female rotor 22 and the male rotor 23 move relative to each other to perform suction and discharge operations, a closed space 31 is formed between the housing 21, the female rotor 22 and the male rotor 23 before suction and discharge are completed and started.

In the working process of gas compression of the screw compressor, the closed space 31 is gradually reduced, the gas pressure in the closed space 31 is gradually increased, and the amplitude of the gas flow pulsation is gradually increased, so that high-pressure gas in the closed space 31 enters the gas flow pulsation attenuation cavity 32 through the damping channel 33 on the cover plate 13, and thus, the gas flow pulsation in the closed space 31 can be attenuated by utilizing the gas buffer formed by the friction attenuation generated by the gas through the damping channel 33 and the gas flow pulsation attenuation cavity 32, and different attenuation effects can be obtained by adjusting the number of the gas flow pulsation attenuation cavities 32, the number of the damping channels 33 on the cover plate 13, the cross-sectional shape or the area and the like. For example, the gas flow pulsations may be further reduced by forming two gas flow pulsation resonance cavities 32, as shown in FIG. 5.

The above description is intended to be illustrative and not restrictive. For example, the above-described examples (or one or more versions thereof) may be used in combination with each other. For example, other embodiments may be used by those of ordinary skill in the art upon reading the above description. In addition, in the foregoing detailed description, various features may be grouped together to streamline the disclosure. This should not be interpreted as an intention that a disclosed feature not claimed is essential to any claim. Rather, the subject matter of the present disclosure may lie in less than all features of a particular disclosed embodiment. Thus, the following claims are hereby incorporated into the detailed description as examples or embodiments, with each claim standing on its own as a separate embodiment, and it is contemplated that these embodiments may be combined with each other in various combinations or permutations. The scope of the disclosure should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

The above embodiments are merely exemplary embodiments of the present disclosure, which is not intended to limit the present disclosure, and the scope of the present disclosure is defined by the claims. Various modifications and equivalents of the disclosure may occur to those skilled in the art within the spirit and scope of the disclosure, and such modifications and equivalents are considered to be within the scope of the disclosure.

Claims

1. The utility model provides an air pulsation damping device, its sets up inside air compressor, air compressor is inside to be provided with enclosure space (31) that is used for gas compression, its characterized in that, including high-pressure exhaust tip (11), splint (12) and at least one apron (13) set up the concave part on splint (12), high-pressure exhaust tip (11) splint (12) with form at least one air pulsation damping chamber (32) between at least one apron (13) be equipped with at least one damping channel (33) on apron (13), damping channel (33) will air pulsation damping chamber (32) with enclosure space (31) are linked together.

2. An airflow pulsation damping device according to claim 1, characterized in that said clamping plate (12) is integrated on said high pressure exhaust end portion (11).

3. The airflow pulsation damping device according to claim 1, wherein said high pressure exhaust end portion (11), said clamping plate (12) and said cover plate (13) are connected by means of screws (14).

4. The airflow pulsation reducing device according to claim 1, wherein the shape of said cover plate (13) is at least one of circular, kidney-shaped, rectangular, triangular, fan-shaped, and arc-shaped.

5. An airflow pulsation damping device according to claim 1, wherein an opening is provided in said cover plate (13) to form said damping channel (33).

6. The airflow pulsation damping device according to claim 1, wherein the cross-sectional shape of said damping channel (33) is at least one of circular, rectangular, triangular, oval, and arc.

7. An airflow pulsation damping device according to claim 1, wherein the cross-sectional shape of said damping channel (33) is gradually variable along the length direction.

8. An air compressor comprising the airflow pulsation damping device of any one of claims 1-7.

9. A screw compressor comprising the gas flow pulsation damping device according to any one of claims 1 to 7. .

10. -screw compressor according to claim 9, characterised in that it comprises a casing (21), inside which casing (21) there are female (22) and male (23) rotors meshing with each other, the casing (21), the female (22) and the male (23) rotors forming between them a closed space (31).