Main air path system of compressor test bench and control method

Abstract

The application discloses a main gas path system of a compressor test bench and a control method, and is suitable for adjusting the airflow of a compressor. The main gas path system comprises: an air inlet valve group, a plurality of main air inlet pipes configured to deliver gas to the air inlet end of the compressor, and a plurality of main air inlet valves configured to respectively adjust the airflow flowing into the air inlet end of the compressor through the main air inlet pipes by adjusting the valve opening degree of the main air inlet valves; an air outlet valve group, a plurality of main air outlet pipes configured to deliver the gas at the air outlet end of the compressor to the air outlet tower, and a plurality of main air outlet valves configured to respectively adjust the airflow flowing through the main air outlet pipes by adjusting the valve opening degree of the main air outlet valves; and a bleed air valve group configured to adjust the pressure of the gas in the compressor, the bleed air valve group comprising a plurality of bleed air pipes configured to respectively deliver the gas between the stages of the compressor, and a plurality of bleed air valves configured to respectively adjust the airflow flowing through the bleed air pipes by adjusting the valve opening degree of the bleed air valves.

Description

Technical Field

[0001] At least one embodiment of this disclosure relates to a main air path system suitable for a compressor, and more particularly to a main air path system and control method for a compressor test bench. Background Technology

[0002] The gas inside the compressor flows almost axially. The moving blades accelerate the fluid, while the stationary blades act as diffusers, converting velocity into pressure rise. This process is similar to the reverse process of a reaction turbine and is the core component of a turbofan engine.

[0003] The main air path system for compressors is the core component of a compressor test bench. The throttling at the inlet, back pressure regulation at the outlet, and interstage bleed air in the main air path system all require precise adjustment via valves to suit different compressor models. Currently, compressor test benches are generally dedicated test benches for single-model compressors, and the inlet and outlet of the main air path system are only adjustable on a single path, making them unsuitable for compressors with wide flow ranges and high power. Summary of the Invention

[0004] To address the existing technical problems, this disclosure provides a main air path system and control method for a compressor test bench, which at least partially solves the above technical problems, thereby obtaining a wide flow rate adjustment range, applicable to different models of compressors, and suitable for compressors with a wide flow rate adjustment range and high power.

[0005] This disclosure provides a main air path system for a compressor test bench, suitable for regulating the airflow of a compressor. The main air path system includes an intake valve assembly installed at the intake end of the compressor. The intake valve assembly includes: multiple main intake pipes configured to supply gas to the intake end of the compressor; and multiple main intake valves configured to regulate the airflow entering the intake end of the compressor through the main intake pipes by adjusting the valve opening of the main intake valves; and an exhaust valve assembly installed at the exhaust end of the compressor. Includes: multiple main exhaust pipes configured to deliver gas from the exhaust end of the compressor to an exhaust tower; and multiple main exhaust valves configured to regulate the airflow flowing through the main exhaust pipes by adjusting the valve opening of the main exhaust valves; and a bleed valve assembly configured to regulate the pressure of the gas within the compressor, the bleed valve assembly including: multiple bleed pipes configured to deliver interstage gas from the compressor; and multiple bleed valves configured to regulate the airflow flowing through the bleed pipes by adjusting the valve opening of the bleed valves.

[0006] Embodiments of this disclosure also provide a control method for the main air path system of a compressor test bench, comprising: when intake throttling is required at the compressor intake end, obtaining a total flow coefficient of multiple main valves based on the total air temperature before the valve, the total air pressure before the valve, and the volumetric flow rate before the valve, wherein the main valve is any one of a main intake valve, a main exhaust valve, or a bleed valve; determining the number of main valves and the flow coefficient of each main valve based on the total flow coefficient; and determining the valve opening degree of each main valve based on the flow coefficient of each main valve.

[0007] According to the main air path system and control method of the compressor test bench provided in this disclosure, during the process of supplying gas to the compressor inlet, the airflow entering the compressor inlet through the main inlet pipe is regulated in multiple ways by adjusting the valve opening of the main inlet valve on multiple main inlet pipes. The airflow discharged from the compressor outlet and flowing through the main outlet pipe is regulated in multiple ways by adjusting the valve opening of the main outlet valve on multiple main outlet pipes. The interstage bleed air flow of the compressor is regulated by adjusting the valve opening of the bleed air valve on multiple bleed air pipes. The inlet valve group, outlet valve group, and bleed air valve group respectively regulate the airflow at the compressor inlet, outlet, and interstage bleed air outlets. Under normal circumstances, the outlet valve group 3 and the bleed air valve group 4 are dynamically coordinated to obtain a wide flow rate adjustment range, which is suitable for different models of compressors. It is suitable for compressors with a wide flow rate adjustment range and high power. It can guide the formulation of the control and adjustment scheme of the main air path system before the test and improve the test safety. Attached Figure Description

[0008] Figure 1 This is a schematic diagram of the working principle of the main air path system of the compressor test bench according to an embodiment of the present disclosure;

[0009] Figure 2 This is a flowchart of a control method for the main air path system of a compressor test bench according to an embodiment of the present disclosure;

[0010] Figure 3 This is a flowchart illustrating the process of obtaining the valve flow coefficient according to an embodiment of this disclosure;

[0011] Figure 4 This is a flowchart illustrating the determination of the number of main valves and the valve opening degree of each main valve according to embodiments of the present disclosure.

[0012] Figure 5 This is a flowchart of a control method for the main air path system of a compressor test bench according to another embodiment of the present disclosure;

[0013] Figure 6 It is the flow-to-total pressure ratio characteristic curve of the compressor test bench; and

[0014] Figure 7This is a flowchart illustrating the determination of the number of auxiliary valves and the valve opening degree of each auxiliary valve according to embodiments of the present disclosure.

[0015] Figure Labels

[0016] 1. Air compressor;

[0017] 2. Intake valve assembly;

[0018] 21. Main intake pipe;

[0019] 22. Main intake valve;

[0020] 23. Auxiliary air intake pipe;

[0021] 24. Auxiliary intake valve;

[0022] 3. Exhaust valve assembly;

[0023] 31. Main exhaust pipe;

[0024] 32. Main exhaust valve;

[0025] 33. Auxiliary exhaust pipe;

[0026] 34. Auxiliary exhaust valve;

[0027] 4. Bleed air valve assembly;

[0028] 41. Breathing tube;

[0029] 42. Air bleed valve. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this disclosure clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0031] However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of this application. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of this application for ease of explanation. However, it will be apparent that one or more embodiments may be implemented without these specific details. Furthermore, descriptions of well-known technologies are omitted in the following description to avoid unnecessarily obscuring the concepts of this application.

[0032] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. The term "comprising" as used herein indicates the presence of features, steps, or operations, but does not exclude the presence or addition of one or more other features.

[0033] When using expressions such as "at least one of A, B, and C," the expression should generally be interpreted in accordance with the meaning commonly understood by a person skilled in the art (e.g., "a system having at least one of A, B, and C" should include, but is not limited to, systems having A alone, having B alone, having C alone, having A and B, having A and C, having B and C, and / or having A, B, and C, etc.). Similarly, when using expressions such as "at least one of A, B, or C," the expression should generally be interpreted in accordance with the meaning commonly understood by a person skilled in the art (e.g., "a system having at least one of A, B, or C" should include, but is not limited to, systems having A alone, having B alone, having C alone, having A and B, having A and C, having B and C, and / or having A, B, and C, etc.).

[0034] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0035] The present invention is described herein with respect to structural embodiments and methods. It should be understood that this is not intended to limit the invention to the specific disclosed embodiments; the invention can be practiced using other features, elements, methods, and embodiments. Similar elements in different embodiments are typically designated with similar numbers.

[0036] The axial compressor is a core component of a turbofan engine. A compressor test bench includes the compressor and a main airflow system suitable for the compressor, with the main airflow system being the core component. By adjusting the intake throttling, exhaust back pressure, and interstage bleed air in the main airflow system, it can be adapted to different compressor models to meet their operating requirements. However, current compressor test benches are generally dedicated test benches for single-model compressors. The intake and exhaust ends of the main airflow system are only adjustable in a single path, making them unsuitable for compressors with wide flow ranges and high power, and also unsuitable for different compressor models.

[0037] Figure 1 This is a schematic diagram of the working principle of the main air path system of the compressor test bench according to an embodiment of the present disclosure.

[0038] Embodiments of this disclosure provide a main air path system for a compressor test bench, such as... Figure 1As shown, the compressor test bench includes a compressor and a main air path system for regulating the airflow of the compressor. The main air path system includes an intake valve assembly 2, an exhaust valve assembly 3, and a bleed valve assembly 4. The intake valve assembly 2 is installed at the intake end of the compressor 1 and is configured to regulate the airflow input to the intake end of the compressor 1. The intake valve assembly 2 includes multiple main intake pipes 21 and multiple main intake valves 22. The multiple main intake pipes 21 are connected to the intake end of the compressor 1 and are configured to deliver gas to the intake end of the compressor 1. The multiple main intake valves 22 are respectively disposed on the main intake pipes 21 and are configured to regulate the airflow flowing through the main intake pipes 21 into the intake end of the compressor 1 by adjusting the valve opening of the main intake valves 22.

[0039] The exhaust valve assembly 3, installed at the exhaust end of the compressor 1, is configured to regulate the airflow discharged from the exhaust end of the compressor 1. The exhaust valve assembly 3 includes multiple main exhaust pipes 31 and multiple main exhaust valves 32. The multiple main exhaust pipes 31 are configured to deliver the gas from the exhaust end of the compressor 1 to the exhaust tower. The multiple main exhaust valves 32 are respectively disposed on the main exhaust pipes 31, and the multiple main exhaust valves 32 are configured to regulate the airflow flowing through the main exhaust pipes 31 by adjusting the valve opening of the main exhaust valves 32.

[0040] The bleed air valve assembly 4 is configured to regulate the pressure of the gas in the compressor 1. The bleed air valve assembly 4 includes a plurality of bleed air pipes 41 and a plurality of bleed air valves 42. The plurality of bleed air pipes 41 are configured to respectively deliver interstage gas of the compressor 1, and the plurality of bleed air valves 42 are configured to respectively regulate the airflow flowing through the bleed air pipes 41 by adjusting the valve opening of the bleed air valves 42.

[0041] In one exemplary embodiment, the intake valve assembly 2 further includes at least one auxiliary intake pipe 23 and at least one auxiliary intake valve 24. The auxiliary intake pipe 23 is connected in parallel with the main intake pipe 21 to form a branch of the main intake pipe 21. The adjustment precision of the auxiliary intake valve 24 is higher than that of the main intake valve 22. The auxiliary intake valve 24 is configured to adjust the airflow flowing through the auxiliary intake pipe 23 by adjusting the valve opening of the auxiliary intake valve 24, and to finely adjust the airflow input to the intake end of the compressor 1.

[0042] In one exemplary embodiment, the exhaust valve assembly 3 further includes at least one auxiliary exhaust pipe 33 and at least one auxiliary exhaust valve 34. The auxiliary exhaust pipe 33 is connected in parallel with the main exhaust pipe 31 to form a branch of the main exhaust pipe 31. The adjustment accuracy of the auxiliary exhaust valve 34 is higher than that of the main exhaust valve 32. The auxiliary exhaust valve 34 is configured to adjust the airflow flowing through the auxiliary exhaust pipe 33 by adjusting the valve opening of the auxiliary exhaust valve 34, and to finely adjust the airflow discharged from the exhaust end of the compressor 1. The intake valve assembly, exhaust valve assembly, and bleed valve assembly respectively adjust the airflow at the intake end, exhaust end, and interstage bleed end of the compressor, thereby obtaining a wide flow rate adjustment range to suit different models of compressors, and is suitable for compressors with a wide flow rate adjustment range and high power.

[0043] The embodiments of this disclosure also propose a control method for the main air path system of a compressor test bench.

[0044] Figure 2 This is a flowchart of a control method for the main air path system of a compressor test bench according to an embodiment of the present disclosure.

[0045] like Figure 1 and 2 As shown, the control method of the main gas path system of the compressor test bench in this embodiment includes operations S110 to S130:

[0046] When operating S110, if throttling of the air intake is required at the intake end of compressor 1, the total flow coefficient of multiple main valves is obtained based on the total air temperature, total air pressure, and volumetric flow rate before the valve. The main valve is any one of the main intake valve 22, main exhaust valve 32, or bleed valve 42.

[0047] In one exemplary embodiment, during operation S110, it is determined whether throttling is required at the inlet of compressor 1 based on the power of compressor 1 or the outlet pressure of compressor 1. If the power of compressor 1 exceeds the maximum power of the compressor test bench, or if the outlet pressure of compressor 1 exceeds the maximum withstand outlet pressure of the exhaust valve assembly in the main air path system of the compressor test bench, throttling is required at the inlet of compressor 1. If throttling is not required at the inlet of compressor 1, the main intake valve 22 and the auxiliary intake valve 24 of the intake valve assembly 2 are fully open.

[0048] In operation S120, the number of main valves and the flow coefficient of each main valve are determined based on the total flow coefficient.

[0049] In operation S130, the valve opening degree of each main valve is determined based on the flow coefficient of each main valve.

[0050] According to embodiments of this disclosure, the total flow coefficient of the plurality of main valves represents the sum of the flow coefficients of each main valve.

[0051] During the process of regulating the input airflow at the inlet of compressor 1, the total flow coefficient of the main intake valve 22 is obtained based on the total airflow temperature before the main intake valve 22, the total airflow pressure before the intake valve, and the volumetric flow rate before the intake valve. Based on the total flow coefficient, the number of main intake valves 22 and the flow coefficient of each main intake valve 22 are determined. Based on the flow coefficient of each main intake valve 22, the valve opening degree of each main valve is determined. The sum of the flow coefficients of each main intake valve 22 constitutes the total flow coefficient of the main intake valves 22.

[0052] Similarly, the method for obtaining the total flow coefficient of the main exhaust valve 32, determining the number of main exhaust valves 32 and the flow coefficient of each main exhaust valve 32, and determining the valve opening of each main exhaust valve 32 is the same as that for the main intake valve 22, and will not be described again here. The method for obtaining the total flow coefficient of the bleed valve 42, determining the number of bleed valves 42 and the flow coefficient of each bleed valve 42, and determining the total valve opening of each bleed valve 42 is the same as that for the main intake valve 22, and will not be described again here.

[0053] By adjusting the valve openings of the main intake valves 22 on multiple main intake pipes 21, the airflow entering the compressor 1 through the main intake pipes 21 is regulated in multiple ways. By adjusting the valve openings of the main exhaust valves 32 on multiple main exhaust pipes 31, the airflow exiting the compressor 1 and flowing through the main exhaust pipes 31 is regulated in multiple ways. By adjusting the valve openings of the bleed valves 42 on multiple bleed pipes 41, the interstage bleed airflow of the compressor 1 is regulated. The intake valve group 2, exhaust valve group 3, and bleed valve group 4 respectively regulate the airflow at the intake, exhaust, and interstage bleed ends of the compressor 1. Under normal circumstances, the exhaust valve group 3 and bleed valve group 4 are dynamically coordinated to obtain a wide flow rate adjustment range suitable for different models of compressor 1. This is suitable for compressor 1 with a wide flow rate adjustment range and high power. It can guide the formulation of the control and adjustment scheme of the main air circuit system before the test, and improve the safety of the test.

[0054] Figure 3 This is a flowchart of obtaining the valve flow coefficient according to an embodiment of the present disclosure.

[0055] like Figure 3 As shown, the flow coefficient of the valve is obtained from operation S210 to operation S220.

[0056] In operation S210, the flow state of the airflow passing through the main valve is determined based on the pressure differential ratio of the main valve. This flow state includes both blocked and non-blocked flow.

[0057] According to embodiments of this disclosure, in operation S210, if the pressure differential ratio is greater than the critical pressure differential ratio, the flow state is determined to be choked flow. If the pressure differential ratio is less than or equal to the critical pressure differential ratio, the flow state is determined to be non-choked flow.

[0058] In operation S220, based on the flow state, the total flow coefficient of multiple main valves is obtained according to the total temperature of the airflow before the valve, the total pressure of the airflow before the valve, and the volumetric flow rate before the valve.

[0059] According to an embodiment of this disclosure, in operation S220, when the flow state is determined to be non-blocked flow, the first flow coefficient expression (1) is obtained as follows:

[0060]

[0061] Among them, K V Where ρ is the flow coefficient, Q is the volumetric flow rate, P is the total pressure of the gas flow, T is the total temperature of the gas flow, and ρ is the flow coefficient. N =1.29kg / m 3 Density under standard conditions Z is the coefficient of thermal expansion, Z is a function of specific pressure and specific temperature, and X is the differential pressure ratio of the valve.

[0062] Based on the first flow coefficient expression (1), the first flow coefficient is obtained according to the total temperature of the airflow before the valve, the total pressure of the airflow before the valve, and the volumetric flow rate before the valve.

[0063] Given that the flow state is choked flow, the expression for the second flow coefficient (2) is:

[0064]

[0065] Among them, K V Where ρ is the flow coefficient, Q is the volumetric flow rate, P is the total pressure of the airflow, T is the total temperature of the airflow, and ρ is the total pressure of the airflow. N =1.29kg / m 3 Let Z be the density under standard conditions, Z be a function of specific pressure and specific temperature, and X be the density. T is the critical differential pressure ratio of the valve, and k is the gas adiabatic index.

[0066] Based on the expression for the second flow coefficient (2), the second flow coefficient is obtained according to the total temperature of the airflow before the valve, the total pressure of the airflow before the valve, and the volumetric flow rate before the valve.

[0067] According to embodiments of this disclosure, the total flow coefficient of multiple main intake valves is obtained based on the total airflow temperature before the main intake valve 22, the total airflow pressure before the main intake valve 22, and the volumetric flow rate before the main intake valve 22.

[0068] Specifically, the total temperature of the airflow before the main intake valve 22 is room temperature; the total pressure of the airflow before the main intake valve 22 is atmospheric pressure (1 bar); the volumetric flow rate before the main intake valve 22 is equal to the sum of the volumetric flow rate of the exhaust gas at the exhaust end of compressor 1 and the volumetric flow rate of the bleed gas from compressor 1. The pressure difference ratio of the valve is the throttling ratio at the intake end of the compressor. Therefore, the total flow coefficient of the main intake valve can be obtained according to the first flow coefficient expression (1) or the second flow coefficient expression (2).

[0069] According to embodiments of this disclosure, the total flow coefficient of a plurality of main intake valves 22 is obtained based on the total airflow temperature before the main exhaust valve 32, the total airflow pressure before the main exhaust valve 32, and the volumetric flow rate before the main exhaust valve 32.

[0070] Specifically, the portion of the main exhaust pipe 31 located at the front end of the main exhaust valve 32 is the pre-valve pipe, and the portion of the main exhaust pipe 31 located at the rear end of the main exhaust valve 32 is the post-valve pipe. The total airflow pressure downstream of the main exhaust valve 32 is obtained based on the outlet cross-sectional area and aerodynamic function of the post-valve pipe.

[0071] The pneumatic function is obtained based on the outlet cross-sectional area of ​​the downstream pipeline. When an ejector nozzle is installed at the outlet of the downstream pipeline, the outlet cross-sectional area of ​​the downstream pipeline is equal to the outlet cross-sectional area of ​​the ejector nozzle. The expression (3) relating the outlet cross-sectional area of ​​the downstream pipeline to the pneumatic function is:

[0072]

[0073] in, This refers to the outlet flow rate at the compressor exhaust end. p is the total airflow temperature at the compressor exhaust end. out The outlet static pressure of the pipeline downstream of the main exhaust valve, A out Let y(λ) be the outlet cross-sectional area of ​​the pipeline downstream of the main exhaust valve, where y(λ) is a pneumatic function and K = 0.404 for air.

[0074] Furthermore, based on the gas flow function, the total pressure of the gas flow after the main exhaust valve 32 is obtained.

[0075] The expressions (4) and (5) relating the gas flow function to the total pressure of the gas flow after the main exhaust valve 32 are as follows:

[0076]

[0077]

[0078] Where q(λ) is the gas flow function, λ is the velocity coefficient at the outlet of the main exhaust valve, k is the gas adiabatic index, and p outThe outlet static pressure of the pipeline downstream of the main exhaust valve. It is the total airflow pressure after the main exhaust valve.

[0079] The pressure difference ratio of the main exhaust valve 32 is obtained based on the total air pressure downstream of the main exhaust valve 32 and the total air pressure upstream of the main exhaust valve 32. The total flow coefficient of multiple main exhaust valves 32 is obtained based on the total air temperature upstream of the main exhaust valve 32, the total air pressure upstream of the main exhaust valve 32, and the volumetric flow rate upstream of the main exhaust valve 32.

[0080] According to embodiments of this disclosure, the total flow coefficient of multiple bleed valves 42 is obtained based on the total gas temperature before the bleed valve 42, the total gas pressure before the bleed valve 42, and the volumetric flow rate before the bleed valve 42. The total gas temperature before the bleed valve 42 is the total gas temperature at the interstage bleed outlet of compressor 1; the total gas pressure before the bleed valve 42 is the total gas pressure at the interstage bleed outlet of compressor 1; and the volumetric flow rate before the bleed valve 42 is the volumetric flow rate of the gas at the interstage bleed outlet of compressor 1.

[0081] According to embodiments of this disclosure, the number of main valves and the flow coefficient of each main valve are determined based on the total flow coefficient. The total valve opening of the multiple main valves is also considered. The total flow coefficient of the multiple main valves represents the sum of the flow coefficients of each main valve. Flow coefficient K V There is a corresponding relationship between the valve opening degree θ and the valve opening degree θ, the relationship being θ = f(K V This allows for the determination of valve opening based on the target flow coefficient. The valve opening of each main valve is determined based on its flow coefficient.

[0082] In an exemplary embodiment, if the total flow coefficient of multiple main valves satisfies the following relationship: the given value of the flow coefficient of the main valve < the total flow coefficient of the multiple main valves < (N) * the preset value of the flow coefficient of the main valve, and N = 1, then the number of main valves is 1.

[0083] According to embodiments of this disclosure, the valve opening range of a single main valve is generally 30-70. For example, the given value of the flow coefficient of the main valve is the flow coefficient corresponding to a valve opening of 30, and the preset value of the flow coefficient of the main valve is the flow coefficient corresponding to a valve opening of 70. If the flow coefficient corresponding to a valve opening of 30 is less than the total flow coefficient of multiple main valves and less than the flow coefficient corresponding to a valve opening of 70, then the number of main valves is 1.

[0084] If the total flow coefficient of multiple main valves satisfies the following relationship: (N-1) * the preset value of the flow coefficient of the main valve < the total flow coefficient of the multiple main valves < (N) * the preset value of the flow coefficient of the main valve, and N > 1, then the number of main valves is N.

[0085] According to embodiments of this disclosure, if the flow coefficient corresponding to a valve opening of 70 (N-1) * 70 < the total flow coefficient of multiple main valves < (N) * the flow coefficient corresponding to a valve opening of 70, and N > 1, then the number of main valves is N. For example, if the valve opening corresponding to the total flow coefficient of multiple main valves is 100, then 1 * 70 < 100 < 2 * 70, and the number of main valves is 2. If the valve opening corresponding to the total flow coefficient of multiple main valves is 160, then 2 * 70 < 160 < 3 * 70, and the number of main valves is 3.

[0086] Figure 4 This is a flowchart illustrating the determination of the number of main valves and the valve opening degree of each main valve according to embodiments of the present disclosure.

[0087] According to embodiments of this disclosure, such as Figure 4 As shown, this embodiment includes operations S401 to S411.

[0088] In operation S301, determine whether throttling is required at the compressor inlet. If yes, proceed to operation S302; otherwise, proceed to operation S303.

[0089] When operating S302, each main valve is fully opened.

[0090] In operation S303, calculate the total flow coefficient of multiple main valves.

[0091] In operation S304, determine if the given value of the flow coefficient of the main valve is less than the total flow coefficient of multiple main valves and the preset value of the flow coefficient of the main valve. If yes, then execute operation S305; otherwise, execute operation S306.

[0092] When operating S305, the number of main valves is 1.

[0093] In operation S306, (N-1)*flow coefficient preset value < total flow coefficient of the multiple main valves < (N)*flow coefficient preset value, and N>1, then the number of main valves is N.

[0094] In operation S307, calculate the flow coefficient of each main valve.

[0095] In operation S308, calculate the valve opening degree of each main valve.

[0096] Operation S309, end.

[0097] Figure 5 This is a flowchart of a control method for the main air path system of a compressor test bench according to another embodiment of the present disclosure.

[0098] According to embodiments of this disclosure, such as Figure 5 As shown, this embodiment includes operations S410 to S430.

[0099] In operation S410, if the valve adjustment accuracy of the main valve exceeds the preset range value, the total flow coefficient change value of multiple auxiliary valves is determined according to the preset range value, wherein the auxiliary valve is either the auxiliary intake valve 24 or the auxiliary exhaust valve 34.

[0100] According to embodiments of this disclosure, in operation S410, if the valve adjustment accuracy of the main valve does not exceed a preset range, the auxiliary valve does not need to be opened. If the valve adjustment accuracy of the main valve exceeds the preset range, and the main valve adjustment accuracy cannot meet the requirements, the auxiliary valve needs to participate in the adjustment.

[0101] In one exemplary embodiment, a first preset range value is determined based on the fluctuation value of the total pressure after the main intake valve 22; the total flow coefficient change value of the plurality of auxiliary intake valves 24 is determined based on the first preset range value. A second preset range value is determined based on the flow coefficient difference between adjacent state points at the same speed of the compressor; the total flow coefficient change value of the plurality of auxiliary exhaust valves 34 is determined based on the second preset range value.

[0102] The preset range values ​​include a first preset range value and a second preset range value.

[0103] According to embodiments of this disclosure, when determining the first preset range value, the initial flow coefficient of the main intake valve 22 is obtained based on the initial total airflow pressure before the main intake valve 22, the total airflow temperature before the main intake valve 22, and the volumetric flow rate before the main intake valve 22. Based on the fluctuation value of the total pressure after the main intake valve 22, the changed final total airflow pressure before the main intake valve 22 is obtained based on the initial total airflow pressure before the main intake valve 22. Based on the final total airflow pressure before the main intake valve 22, the total airflow temperature before the main intake valve 22, and the volumetric flow rate before the main intake valve 22, the final flow coefficient of the main intake valve 22 is obtained. The difference between the final flow coefficient of the main intake valve 22 and the initial flow coefficient of the main intake valve 22 is the first preset range value. When the valve adjustment accuracy of the main intake valve 22 exceeds the first preset range value, the total flow coefficient change value of the multiple auxiliary intake valves 24 is determined based on the first preset range value.

[0104] According to embodiments of this disclosure, when determining the second preset range value, the compressor test bench has multiple state points at the same equivalent speed of the compressor 1. Figure 6This is the flow-to-total pressure ratio characteristic curve of the compressor test bench. The difference in flow coefficient between adjacent state points at the same speed of compressor 1 is the second preset range value. If the valve adjustment accuracy of the main exhaust valve 32 exceeds the second preset range value, the total flow coefficient change value of multiple auxiliary exhaust valves 34 is determined according to the second preset range value. During the recording of the compressor's flow-to-total pressure ratio characteristic curve, the exhaust valve group needs to be dynamically adjusted. A data table of the compressor test bench state points and the model and opening degree of the main exhaust valve of the exhaust valve group needs to be drawn. During the test, the main exhaust valve is adjusted according to the data table of the compressor test bench state points and the exhaust valve group.

[0105] In operation S420, the number of auxiliary valves and the flow coefficient of each auxiliary valve are determined based on the total flow coefficient change value of multiple auxiliary valves.

[0106] In an exemplary embodiment, during operation S420, if the change in the total flow coefficient of the multiple auxiliary valves satisfies the following relationship: the minimum value of the flow coefficient of the auxiliary valve < the change in the total flow coefficient of the multiple auxiliary valves < the maximum value of the flow coefficient of the auxiliary valves, then the number of auxiliary valves is 1.

[0107] If the total flow coefficient change of multiple auxiliary valves satisfies the following relationship: the total flow coefficient change of multiple auxiliary valves > the maximum flow coefficient of the auxiliary valves, then the number of auxiliary valves is 2.

[0108] According to embodiments of this disclosure, the total flow coefficient change of the multiple auxiliary valves is the sum of the flow coefficients of each auxiliary valve. When the total flow coefficient change of the multiple auxiliary valves falls within the range of the minimum and maximum flow coefficients of the auxiliary valves, there is one auxiliary valve. When the total flow coefficient change of the multiple auxiliary valves exceeds the maximum flow coefficient of the auxiliary valves, there are two auxiliary valves. Generally, two auxiliary valves are set to represent the upper limit of the flow rate of compressor 1.

[0109] In operation S430, the valve opening degree of each auxiliary valve is determined based on the flow coefficient of each auxiliary valve.

[0110] Specifically, the flow coefficient K V There is a corresponding relationship between the valve opening degree θ and the valve opening degree θ, the relationship being θ = f(K V Based on the number and model of valves, and the relationship curve between valve opening and flow coefficient, the valve opening of each auxiliary valve is determined according to the flow coefficient of each auxiliary valve.

[0111] Figure 7 This is a flowchart illustrating the determination of the number of auxiliary valves and the valve opening degree of each auxiliary valve according to embodiments of the present disclosure.

[0112] According to embodiments of this disclosure, such as Figure 7As shown, this embodiment includes operations S501 to S509.

[0113] In operation S501, determine whether the valve adjustment accuracy of the main valve exceeds the preset range. If not, proceed to operation S502; if yes, proceed to operation S503.

[0114] When operating S502, all auxiliary valves are closed.

[0115] In operation S503, the total flow coefficient change value of multiple auxiliary valves is determined according to the preset range value.

[0116] In operation S504, determine if the minimum flow coefficient value of the auxiliary valve is less than the total change in the flow coefficient of multiple auxiliary valves and the maximum flow coefficient value of the auxiliary valve. If yes, then execute operation S505; otherwise, execute operation S506.

[0117] When operating S505, the number of auxiliary valves is 1.

[0118] In operation S506, if the total flow coefficient change of multiple auxiliary valves is greater than the maximum flow coefficient value of the auxiliary valves, then the number of auxiliary valves is 2.

[0119] In operation S507, calculate the flow coefficient of each auxiliary valve.

[0120] In operation S508, calculate the valve opening degree of each auxiliary valve.

[0121] Operation S509, end.

[0122] According to the main air path system and control method for a compressor provided in this disclosure, during the process of supplying gas to the inlet end of the compressor 1, the airflow entering the inlet end of the compressor 1 through the main inlet pipe 21 is regulated in multiple ways by adjusting the valve opening of the main inlet valve 22 on the multiple main inlet pipes 21; the airflow discharged from the outlet end of the compressor 1 and flowing through the main exhaust pipe 31 is regulated in multiple ways by adjusting the valve opening of the main exhaust valve 32 on the multiple main exhaust pipes 31; and the airflow discharged from the outlet end of the compressor 1 and flowing through the main exhaust pipe 31 is regulated by adjusting the bleed valve on the multiple bleed pipes 41. The valve opening of 42 is adjusted to regulate the interstage bleed air flow of compressor 1. The inlet valve group 2, the exhaust valve group 3, and the bleed air valve group 4 respectively regulate the air flow at the inlet end, exhaust end, and interstage bleed air of compressor 1. Under normal circumstances, the exhaust valve group 3 and the bleed air valve group 4 are dynamically coordinated to obtain a wide flow rate adjustment range, which is suitable for different models of compressor 1. It is suitable for compressor 1 with a wide flow rate adjustment range and high power. It can guide the formulation of the control and adjustment scheme of the main air circuit system before the test and improve the safety of the test.

[0123] The above specific embodiments further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A control method for the main air path system of a compressor test bench, characterized in that, The main air path system is suitable for regulating the airflow of the compressor and includes: An intake valve assembly (2) is installed at the intake end of the compressor (1), and the intake valve assembly (2) includes: Multiple main intake pipes (21) are configured to deliver gas to the intake end of the compressor (1); and Multiple main intake valves (22) are configured to adjust the airflow entering the compressor (1) through the main intake pipe (21) by adjusting the valve opening of the main intake valves (22); An exhaust valve assembly (3) is installed at the exhaust end of the compressor (1), and the exhaust valve assembly (3) includes: Multiple main exhaust pipes (31) are configured to deliver gas from the exhaust end of the compressor (1) to an exhaust tower; and Multiple main exhaust valves (32) are configured to regulate the airflow through the main exhaust pipe (31) by adjusting the valve opening of the main exhaust valves (32); A bleed valve assembly (4) is configured to regulate the pressure of the gas within the compressor (1), the bleed valve assembly (4) comprising: Multiple bleed tubes (41) are configured to respectively deliver interstage gas from the compressor (1); and Multiple air intake valves (42) are configured to regulate the airflow through the air intake pipe (41) by adjusting the valve opening of the air intake valves (42); The control method includes: When throttling is required at the inlet of the compressor (1), the flow state of the airflow passing through the main valve is determined according to the pressure difference ratio of the main valve, wherein the flow state includes blocked flow and non-blocked flow; based on the flow state, the total flow coefficient of the multiple main valves is obtained according to the total air temperature before the valve, the total air pressure before the valve, and the volumetric flow rate before the valve, including: Given that the flow state is determined to be non-blocked flow, the expression for the first flow coefficient is obtained as follows: ； in, For flow coefficient, Volumetric flow rate, The total pressure of the airflow. The total temperature of the airflow. Density under standard conditions The coefficient of thermal expansion is 1 / 3. It is a function of specific pressure and specific temperature. This refers to the differential pressure ratio of the valve. Based on the first flow coefficient expression, the first flow coefficient is obtained according to the total temperature of the airflow before the valve, the total pressure of the airflow before the valve, and the volumetric flow rate before the valve; Given that the flow state is determined to be choked flow, the expression for the second flow coefficient is obtained as follows: ； in, For flow coefficient, Volumetric flow rate, The total pressure of the airflow. The total temperature of the airflow. Density under standard conditions It is a function of specific pressure and specific temperature. This represents the critical differential pressure ratio of the valve. The gas adiabatic index; Based on the expression for the second flow coefficient, the second flow coefficient is obtained according to the total temperature of the airflow before the valve, the total pressure of the airflow before the valve, and the volumetric flow rate before the valve. Based on the total flow coefficient, determine the number of main valves and the flow coefficient of each main valve; Based on the flow coefficient of each main valve, the valve opening degree of each main valve is determined; The main valve is any one of the main intake valve (22), the main exhaust valve (32), or the bleed valve (42).

2. The control method according to claim 1, characterized in that, The intake valve assembly (2) also includes: At least one auxiliary air intake pipe (23) is connected in parallel with the main air intake pipe (21) to form a branch of the main air intake pipe (21); At least one auxiliary intake valve (24) is configured to regulate the airflow flowing through the auxiliary intake pipe (23) and finely regulate the airflow input to the intake end of the compressor (1) by adjusting the valve opening of the auxiliary intake valve (24).

3. The control method according to claim 2, characterized in that, The exhaust valve assembly (3) also includes: At least one auxiliary exhaust pipe (33) is connected in parallel with the main exhaust pipe (31) to form a branch of the main exhaust pipe (31); At least one auxiliary exhaust valve (34) is configured to regulate the airflow flowing through the auxiliary exhaust pipe (33) and finely regulate the airflow discharged from the exhaust end of the compressor (1) by adjusting the valve opening of the auxiliary exhaust valve (34).

4. The control method according to claim 1, characterized in that, Determining the flow state of the airflow passing through the main valve based on the pressure differential ratio of the main valve includes: If the pressure differential ratio is greater than the critical pressure differential ratio, the flow state is determined to be choked flow. When the pressure differential ratio is less than or equal to the critical pressure differential ratio, the flow state is determined to be non-blocked flow.

5. The control method according to claim 1, characterized in that, If the total flow coefficient of the plurality of main valves satisfies the following relationship: If the preset value of the flow coefficient of the main valve is (N-1) * and the total flow coefficient of the multiple main valves is (N) * the preset value of the flow coefficient of the main valve, and N > 1, then the number of the main valves is N. If the total flow coefficient of the plurality of main valves satisfies the following relationship: If the given value of the flow coefficient of the main valve is less than the total flow coefficient of the multiple main valves and less than (N) * the preset value of the flow coefficient of the main valve, and N=1, then the number of the main valves is 1.

6. The control method according to claim 3, characterized in that, Also includes: When the valve adjustment accuracy of the main valve exceeds the preset range value, the total flow coefficient change value of multiple auxiliary valves is determined according to the preset range value, wherein the auxiliary valve is any one of the auxiliary intake valve (24) or the auxiliary exhaust valve (34); Based on the total flow coefficient change value of multiple auxiliary valves, the number of multiple auxiliary valves and the flow coefficient of each auxiliary valve are determined; Based on the flow coefficient of each of the auxiliary valves, the valve opening degree of each of the auxiliary valves is determined; The step of determining the total flow coefficient change value of multiple auxiliary valves according to the preset range value includes: Based on the fluctuation value of the total pressure after the main intake valve (22), a first preset range value is determined; Based on the first preset range value, determine the total flow coefficient change value of the plurality of auxiliary intake valves (24); A second preset range value is determined based on the difference in flow coefficients between adjacent state points at the same rotational speed of the compressor; Based on the second preset range value, determine the total flow coefficient change value of the plurality of auxiliary exhaust valves (34); The preset range value includes the first preset range value and the second preset range value, and the total flow coefficient change value of the auxiliary valve includes the total flow coefficient change value of the auxiliary intake valve (24) and the total flow coefficient change value of the auxiliary exhaust valve (34).

7. The control method according to claim 6, characterized in that, If the total flow coefficient change of the plurality of auxiliary valves satisfies the following relationship: If the total flow coefficient change of the multiple auxiliary valves is greater than the maximum flow coefficient value of the auxiliary valves, then the number of auxiliary valves is 2. If the total flow coefficient change of the plurality of auxiliary valves satisfies the following relationship: If the minimum value of the flow coefficient of the auxiliary valve is less than the total change in the flow coefficient of the multiple auxiliary valves, and the maximum value of the flow coefficient of the auxiliary valves is less than the maximum value of the flow coefficient of the auxiliary valves, then the number of auxiliary valves is 1.

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