Detection device for diffuser and diffuser for compressor

Abstract

The invention relates to a diffuser of a compressor, in particular to a detection device for a diffuser and the diffuser for the compressor, and aims to solve the problem of low blade adjusting precision of an existing diffuser. In order to achieve the purpose, the detection device for the diffuser comprises a body, a first detection assembly and a second detection assembly, and the first detection assembly and the second detection assembly are arranged on the body. The first detection assembly can detect the bending deformation of the body in the first detection direction, and the second detection assembly can detect the bending deformation of the body in the second detection direction. The first detection direction and the second detection direction are perpendicular to each other, and the bending direction of the body can be obtained according to the bending deformation of the body in the first detection direction and the bending deformation of the body in the second detection direction. The air flow in the diffuser can make the body bend and deform, and the detection device can detect the bending direction of the body, so that the detection device can detect the direction of the air flow in the diffuser.

Description

Technical Field

[0001] The present invention relates to a diffuser of a compressor, and specifically provides a detection device for a diffuser and a diffuser for a compressor. Background Art

[0002] The principle of a centrifugal compressor is as follows: the blades inside the compressor rotate at a high speed, causing the gas inside the compressor to be subjected to centrifugal force and enter the diffuser; the diffuser decelerates the high-speed gas, and according to Bernoulli's principle, the deceleration process converts the kinetic energy of the gas into the pressure of the gas to increase the gas pressure; then, the gas enters the next stage of the compressor, and the processes of blade acceleration and diffuser deceleration and pressure increase are carried out again; finally, the pressurized air flow is discharged from the compressor.

[0003] The diffuser includes a vaneless diffuser and a vane diffuser. Vanes are arranged inside the vane diffuser to reduce the speed of the air flow through the vanes. The traditional diffuser vanes are fixedly arranged and can only decelerate and pressurize the high-speed gas with the best efficiency when the compressor is in the design condition. When deviating from the design condition, the efficiency will drop sharply, and the range of the design condition is relatively narrow. Therefore, the prior art proposes to set the diffuser vanes as a structure with adjustable angles, and adjust the vane angles according to the actual working conditions to keep the diffuser at a high efficiency.

[0004] The prior art usually adjusts the diffuser vanes according to external factors such as the gas flow output by the compressor and the main shaft speed of the compressor. However, there are a large number of other influencing factors between the vane angles and the above external factors, resulting in a very low accuracy of this adjustment and control method.

[0005] Therefore, there is an urgent need in the art for a detection device for a diffuser and a diffuser for a compressor to solve the above problems. Summary of the Invention

[0006] The present invention aims to solve the above technical problems, that is, to solve the problem of low adjustment accuracy of the existing diffuser vanes.

[0007] In a first aspect, the present invention provides a detection device for a diffuser, which includes a detection device body, a first detection component, and a second detection component. The body is arranged inside the diffuser, and both the first detection component and the second detection component are arranged on the body;

[0008] When the air flow inside the diffuser causes the body to bend and deform, the first detection component can detect the amount of bending deformation of the body in the first detection direction, and the second detection component can detect the amount of bending deformation of the body in the second detection direction;

[0009] The first detection direction and the second detection direction are arranged at an angle. Based on the bending deformation amount of the body in the first detection direction and the bending deformation amount in the second detection direction, the direction of the airflow in the diffuser can be obtained.

[0010] In a specific embodiment of the above detection device, the body includes:

[0011] A deformation part that can elastically bend and deform when affected by an external force;

[0012] A connecting part that can be connected to the diffuser.

[0013] In a specific embodiment of the above detection device, the first detection component includes a first strain gauge and a first detection circuit. The first strain gauge is arranged on the deformation part, and the first strain gauge is electrically connected to the first detection circuit. When the deformation part bends and deforms, the first detection circuit can detect the change in the resistance value of the first strain gauge to determine the bending deformation amount of the deformation part in the first detection direction; and / or

[0014] The second detection component includes a second strain gauge and a second detection circuit. The second strain gauge is arranged on the deformation part, and the second strain gauge is electrically connected to the second detection circuit. When the deformation part bends and deforms, the second detection circuit can detect the change in the resistance value of the second strain gauge to determine the bending deformation amount of the deformation part in the second detection direction.

[0015] In a specific embodiment of the above detection device, the first detection component includes two of the first strain gauges, and the two first strain gauges are respectively arranged on both sides of the deformation part. The direction of the line connecting the two first strain gauges is the first detection direction; and / or

[0016] The second detection component includes two of the second strain gauges, and the two second strain gauges are respectively arranged on both sides of the deformation part. The direction of the line connecting the two second strain gauges is the second detection direction.

[0017] In a specific embodiment of the above detection device, the two first strain gauges and the first detection circuit form a Wheatstone bridge circuit, and the two second strain gauges and the second detection circuit are Wheatstone bridge circuits. The excitation voltage of the first detection circuit is equal to the excitation voltage of the second detection circuit;

[0018] When the deformation part does not deform, the resistance values of the two first strain gauges are equal to the resistance values of the two second strain gauges;

[0019] The bending direction of the body can be obtained based on the detection voltage of the first detection circuit and the detection voltage of the second detection circuit.

[0020] In the specific embodiment of the above detection device, the first detection direction and the second detection direction are perpendicularly arranged, and the bending direction angle θ of the deformation part is:

[0021]

[0022] In the formula, r is the resistance value of the first strain gauge and the resistance value of the second strain gauge when the deformation part does not deform, U is the excitation voltage of the first detection circuit and the excitation voltage of the second detection circuit, u x is the detection voltage of the first detection circuit, u y is the detection voltage of the second detection circuit.

[0023] In the specific embodiment of the above detection device, the shape of the deformation part is cylindrical; and / or

[0024] The material of the deformation part is a linear material.

[0025] In the specific embodiment of the above detection device, a through hole is provided on the body;

[0026] The circuit connection line between the first strain gauge and the first detection circuit passes through the through hole; and / or

[0027] The circuit connection line between the second strain gauge and the second detection circuit passes through the through hole.

[0028] In a second aspect, the present invention provides a diffuser for a compressor, and the diffuser includes the above detection device.

[0029] In the specific embodiment of the above diffuser, blades are provided in the diffuser, the detection device can detect the air flow direction in the diffuser, and the angle of the blades can be adjusted according to the air flow direction.

[0030] In the case of adopting the above technical solutions, the first detection component of the present invention can detect the bending deformation amount of the body in the first detection direction, and the second detection component can detect the bending deformation amount of the body in the second detection direction. The first detection direction and the second detection direction are arranged at an angle. Based on the bending deformation amount of the body in the first detection direction and the bending deformation amount in the second detection direction, the bending direction of the body can be obtained. The detection device is arranged in the diffuser, and the air flow in the diffuser can drive the body to bend and deform. The detection device can detect the bending direction of the body, and this bending direction is the air flow direction. Therefore, the detection device can detect the air flow direction in the diffuser.

[0031] Furthermore, the first detection component includes two first strain gauges and a first detection circuit. The two first strain gauges are respectively arranged on both sides of the deformation part, and the two first strain gauges and the first detection circuit form a Wheatstone bridge circuit. When the body undergoes bending deformation, the resistance value of the first strain gauge changes, and the detection voltage of the first detection circuit also changes accordingly. According to the detection voltage, the bending deformation amount of the body in the first detection direction can be determined. Similarly, the second detection component can determine the bending deformation amount of the body in the second detection direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings, in which:

[0033] Figure 1 is a schematic external structure diagram of the detection device provided by the present invention;

[0034] Figure 2 is a schematic internal structure diagram of the detection device provided by the present invention;

[0035] Figure 3 is a schematic top view structure diagram of the detection device provided by the present invention;

[0036] Figure 4 is a schematic structure diagram of the first detection circuit provided by the present invention;

[0037] Figure 5 is a schematic structure diagram of the second detection circuit provided by the present invention;

[0038] Figure 6 is a schematic diagram of the azimuth relationship between strain gauge A, strain gauge a, strain gauge B, strain gauge b and the bending direction angle θ of the body. In the figure, the connection line A-a is the connection line between strain gauge A and strain gauge a, that is, the first detection direction; the connection line B-b is the connection line between strain gauge B and strain gauge b, that is, the second detection direction; the angle marked as θ is the bending direction angle of the body.

[0039] LIST OF REFERENCE NUMERALS:

[0040] 11. Deformation part; 12. Connection part; 131. Cross hole; 132. Central hole; 14. Convex ring; 15. Nut; 16. Circuit connection line. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0041] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principle of the present invention and are not intended to limit the protection scope of the present invention.

[0042] It should be noted that in the description of the present invention, the terms indicating directions or positional relationships such as "upper", "lower", "left", "right", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings. This is only for the convenience of description and does not indicate or imply that the device or component must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0043] In addition, it should be noted that in the description of the present invention, unless otherwise clearly defined and limited, the terms "installation", "setting", "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and can also be the communication inside two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0044] To solve the problem of low blade adjustment accuracy of the diffuser, the present embodiment discloses a centrifugal compressor. The centrifugal compressor includes a diffuser, in which blades and a detection device are provided. The blades can rotate, and the detection device can detect the airflow direction in the diffuser. According to the airflow direction in the diffuser, adjusting the angle of the blades can keep the diffuser at the best working efficiency.

[0045] Regarding the detection device, it should be noted that although the detection device in this embodiment is applied to the diffuser, this setting method is not a limitation to the present invention. Without departing from the principle of the present invention, those skilled in the art can also apply this detection device in other situations in other embodiments. This detection device can detect the airflow direction, and can also detect the flow direction of liquids or other fluids, which does not deviate from the basic principle of the present invention, and thus will fall within the protection scope of the present invention.

[0046] Regarding the diffuser, it should be noted that although the diffuser in this embodiment is applied to the centrifugal compressor, this setting method is not a limitation to the present invention. Without departing from the principle of the present invention, those skilled in the art can also apply this diffuser to other types of compressors in other embodiments, which does not deviate from the basic principle of the present invention, and thus will fall within the protection scope of the present invention.

[0047] The detection device is used to detect the airflow direction in the diffuser. The detection device includes a body, a first detection component and a second detection component.

[0048] Refer to Figure 1, the main body includes a deformable part 11 and a connecting part 12. The deformable part 11 is in the shape of a slender cylinder, and the deformable part 11 can elastically bend and deform under the influence of air flow. The deformable part 11 is made of a linear material, so that the force on the deformable part 11 and the deformation amount are in a linear relationship, in order to measure the air flow direction.

[0049] The connecting part 12 is in the shape of a cylinder. External threads are provided on the outer wall of the connecting part 12, and a convex ring 14 is provided at one end of the connecting part 12. The external threads of the connecting part 12 can connect to a nut 15, and the convex ring 14 and the nut 15 can clamp an external structure, so that the main body is connected to the diffuser. Further, the deformable part 11 and the connecting part 12 are integrally formed, and the cylindrical deformable part 11 and the cylindrical connecting part 12 are coaxially arranged.

[0050] Regarding the connecting part 12, it should be noted that although the shape of the connecting part 12 is given in this embodiment, these setting methods are not limitations to the present invention. Without departing from the principle of the present invention, those skilled in the art can also adopt other setting methods in other embodiments. For example: the connecting part 12 adopts a prism, a sphere, a cone or other shapes. These changes do not deviate from the basic principle of the present invention, so they will fall within the protection scope of the present invention.

[0051] Regarding the connecting part 12, it should be noted that although the structure in which the connecting part 12 is connected to the diffuser through the nut 15 and the convex ring 14 is given in this embodiment, these setting methods are not limitations to the present invention. Without departing from the principle of the present invention, those skilled in the art can also adopt other setting methods in other embodiments. For example: threaded holes are provided on the diffuser, and the connecting part 12 can be threadedly connected to the threaded holes; or threaded holes are provided on the connecting part 12, convex blocks are provided on the diffuser, external threads are provided on the convex blocks, and the convex blocks and the threaded holes can be threadedly connected to connect the connecting part 12 to the diffuser, etc. As long as the connecting part 12 can install the main body on the diffuser. These changes do not deviate from the basic principle of the present invention, so they will fall within the protection scope of the present invention.

[0052] Regarding the connecting part 12, it should be noted that although the connecting part 12 and the deformable part 11 are integrally formed in this embodiment, these setting methods are not limitations to the present invention. Without departing from the principle of the present invention, those skilled in the art can also adopt other setting methods in other embodiments. For example: the connecting part 12 and the deformable part 11 are divided into two parts and are detachably connected through structures such as threads and snap connections, as long as the connecting part 12 can install the main body on the diffuser. These changes do not deviate from the basic principle of the present invention, so they will fall within the protection scope of the present invention.

[0053] Refer to Figure 2 and Figure 3, a through hole is also provided on the body, and the through hole is used to arrange the circuit connection lines 16 of the first detection component and the circuit connection lines 16 of the second detection component. The through hole includes a cross hole 131 and a central hole 132. The cross hole 131 is arranged at the end of the deformation part 11, and four openings are formed on the outer wall of the deformation part 11 by the cross hole 131. The central hole 132 extends along the axis of the body, one end of the central hole 132 forms an opening on the end face of the connection part 12, and the other end of the central hole 132 communicates with the center of the cross hole 131.

[0054] It should be noted that regarding the through hole, although the through hole in this embodiment includes a cross hole 131 and a central hole 132, this setting method is not a limitation on the present invention. Without deviating from the principle of the present invention, those skilled in the art can also adopt other setting methods in other embodiments, as long as the shape of the through hole does not affect the detection of the air flow direction by the detection device, which does not deviate from the basic principle of the present invention, and thus will fall within the protection scope of the present invention.

[0055] The first detection component includes two first strain gauges and a first detection circuit. Refer to Figure 1 and Figure 3 , the two first strain gauges are respectively a strain gauge A and a strain gauge a, and the strain gauge A and the strain gauge a are respectively arranged on both sides of the outer wall of the cylindrical surface of the deformation part 11. In other words, the connection line between the strain gauge A and the strain gauge a passes through the axis of the cylindrical deformation part 11. The connection line direction between the strain gauge A and the strain gauge a is the first detection direction. When the deformation part 11 undergoes bending deformation, the strain gauge A and the strain gauge a will deform accordingly, causing the resistance values of the strain gauge A and the strain gauge a to change. According to the resistance change values of the above two, the bending deformation amount of the deformation part 11 in the first detection direction can be obtained. Refer to Figure 2 , the connection line of the strain gauge A enters the through hole through an opening of the cross hole 131 and extends out of the opening of the central hole 132 to connect the first detection circuit. The connection line of the strain gauge a enters the through hole through another opening of the cross hole 131 and extends out of the opening of the central hole 132 to connect the first detection circuit. Refer to Figure 4 , the first detection circuit includes two resistors, and the strain gauge A, the strain gauge a are connected with these two resistors to form a Wheatstone bridge circuit. When the resistance values of the strain gauge A and the strain gauge a change, the detection voltage of the first detection circuit changes accordingly.

[0056] The second detection component includes two second strain gauges and a second detection circuit. Refer to Figure 1 and Figure 3, the two second strain gauges are strain gauge B and strain gauge b respectively. Strain gauge B and strain gauge b are respectively arranged on both sides of the outer wall of the cylindrical surface of the deformation part 11. In other words, the line connecting strain gauge B and strain gauge b passes through the axis of the cylindrical deformation part 11. The direction of the line connecting strain gauge B and strain gauge b is the second detection direction. When the deformation part 11 undergoes bending deformation, strain gauge B and strain gauge b will deform accordingly, causing the resistance values of strain gauge B and strain gauge b to change. According to the resistance change values of the above two, the bending deformation amount of the deformation part 11 in the second detection direction can be obtained. Refer to Figure 2 , the connecting wire of strain gauge B enters the through hole through an opening of the cross hole 131 and extends out of the opening of the central hole 132 to connect the second detection circuit. The connecting wire of strain gauge b enters the through hole through the other opening of the cross hole 131 and extends out of the opening of the central hole 132 to connect the second detection circuit. Refer to Figure 5 , the second detection circuit includes two resistors. Strain gauge B, strain gauge b and these two resistors are connected into a Wheatstone bridge circuit. When the resistance values of strain gauge B and strain gauge b change, the detection voltage of the second detection circuit changes accordingly.

[0057] The working principle of this detection device is as follows: This detection device is arranged in the diffuser, and the airflow in the diffuser can drive the deformation part 11 of the body to deform. When the deformation part 11 deforms, the strain gauges A, a, B, and b on the deformation part 11 deform accordingly. After the strain gauges deform, their resistance values also change, resulting in a change in the detection voltage of the bridge circuit corresponding to the strain gauges. According to the change in the detection voltage, the deformation amount of the body in the detection direction corresponding to the detection circuit can be determined. Combining the bending deformation amount of the body in the first detection direction and the bending deformation amount in the second detection direction, the bending direction angle of the body can be determined. The bending direction angle of this body is the airflow direction in the diffuser.

[0058] Furthermore, the first detection direction and the second detection direction are perpendicularly arranged, as shown in Figure 6 . This setting method is convenient for calculating and obtaining the bending direction of the deformation part 11. The excitation voltage of the first detection circuit is equal to the excitation voltage of the second detection circuit. Strain gauges A, a, B, and the strain gauges are all set as the same type of strain gauges. Specifically, when the deformation part 11 does not deform, the resistance values of strain gauge A, strain gauge a, strain gauge B, and strain gauge b are all set to be equal; and the relationship between the deformation of the strain gauges and the change in resistance values is the same. In other words, when different strain gauges undergo the same degree of deformation, the resistance values are the same.

[0059] Under the above conditions, the formula for calculating the bending direction angle of the deformation part 11 is as follows:

[0060] Wherein, θ is the bending direction angle of the body, r is the resistance value of the first strain gauge and the second strain gauge when the body is not deformed, U is the excitation voltage of the first detection circuit and the excitation voltage of the second detection circuit, and u x is the detection voltage of the first detection circuit, and u y is the detection voltage of the second detection circuit.

[0061] The detection device can detect the air flow direction in the diffuser. The diffuser can control the blade direction in the diffuser according to the air flow direction, so that the blade direction adapts to the air flow direction, so as to make the efficiency of the diffuser reach the optimal state. Specifically, the diffuser further includes a driving device and a control module. The driving device is connected to the blade, and the driving device can drive the blade to rotate to adjust the angle of the blade. The detection device and the driving device are both electrically connected to the control module. The control module can receive the air flow direction detected by the detection device and control the driving device according to the air flow direction to control the blade angle, so that the blade angle matches the air flow direction, so as to make the diffuser reach the optimal efficiency.

[0062] The control module is configured to execute the control method of the diffuser blades. The control module can be only configured to execute this control method and does not execute other operation controls of the diffuser. Other operation controls can be equipped with other control modules; or it can be configured to execute other operation controls of the diffuser in addition to executing this control method, that is, the control module is a comprehensive execution module, that is, it executes each program during the operation of the diffuser.

[0063] So far, the technical solution of the present invention has been described in conjunction with the preferred embodiments shown in the drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the protection scope of the present invention.

Claims

1. A detection device for a diffuser, characterized in that, It includes a body, a first detection component, and a second detection component. The body is arranged inside the diffuser, and both the first detection component and the second detection component are arranged on the body; When the airflow in the diffuser drives the body to bend and deform, the first detection component can detect the amount of bending deformation of the body in the first detection direction, and the second detection component can detect the amount of bending deformation of the body in the second detection direction; The first detection direction and the second detection direction are arranged at an angle. Based on the amount of bending deformation of the body in the first detection direction and the amount of bending deformation in the second detection direction, the direction of the airflow in the diffuser can be obtained.

2. The detection device according to claim 1, wherein The body includes: A deformation part (11) that can elastically bend and deform when affected by an external force; A connection part (12) that can be connected to the diffuser.

3. The detection device according to claim 2, characterized in that, The first detection component includes a first strain gauge and a first detection circuit. The first strain gauge is arranged on the deformation part (11), and the first strain gauge is electrically connected to the first detection circuit. When the deformation part (11) bends and deforms, the first detection circuit can detect the change in the resistance value of the first strain gauge to determine the amount of bending deformation of the deformation part (11) in the first detection direction; and / or The second detection component includes a second strain gauge and a second detection circuit. The second strain gauge is arranged on the deformation part (11), and the second strain gauge is electrically connected to the second detection circuit. When the deformation part (11) bends and deforms, the second detection circuit can detect the change in the resistance value of the second strain gauge to determine the amount of bending deformation of the deformation part (11) in the second detection direction.

4. The detection device according to claim 3, wherein The first detection component includes two of the first strain gauges, and the two first strain gauges are respectively arranged on both sides of the deformation part (11). The direction of the line connecting the two first strain gauges is the first detection direction; and / or The second detection component includes two of the second strain gauges, and the two second strain gauges are respectively arranged on both sides of the deformation part (11). The direction of the line connecting the two second strain gauges is the second detection direction.

5. The detection device according to claim 4, characterized in that The two first strain gauges and the first detection circuit form a Wheatstone bridge circuit, and the two second strain gauges and the second detection circuit are Wheatstone bridge circuits. The excitation voltage of the first detection circuit and the excitation voltage of the second detection circuit are equal; When the deformation part (11) does not deform, the resistance values of the two first strain gauges and the resistance values of the two second strain gauges are equal; Based on the detection voltage of the first detection circuit and the detection voltage of the second detection circuit, the bending direction of the body can be obtained.

6. The detection device according to claim 4, characterized in that, The first detection direction and the second detection direction are arranged perpendicular to each other. The bending direction angle θ of the deformation part (11) is: Wherein, r is the resistance value of the first strain gauge and the resistance value of the second strain gauge when the deformation part (11) does not deform, U is the excitation voltage of the first detection circuit and the excitation voltage of the second detection circuit, and u x is the detection voltage of the first detection circuit, and u y is the detection voltage of the second detection circuit.

7. The detection device according to claim 2, characterized in that The shape of the deformation part (11) is cylindrical; and / or The material of the deformation part (11) is a linear material.

8. The detection device according to claim 2, wherein There are through holes arranged on the body; The circuit connection line (16) between the first strain gauge and the first detection circuit is disposed through the through hole; and / or The circuit connection line (16) between the second strain gauge and the second detection circuit is disposed through the through hole.

9. A diffuser for a compressor, characterized in that, Comprising the detection device according to any one of claims 1-8.

10. The diffuser according to claim 9, characterized in that, A vane is disposed in the diffuser, and the detection device can detect the air flow direction in the diffuser, and the angle of the vane can be adjusted according to the air flow direction.

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