Method for obtaining temperature rise efficiency of gas compressor

Abstract

A compressor temperature rise efficiency obtaining method is used for reducing errors of temperature rise efficiency. The compressor temperature rise efficiency obtaining method comprises the steps that S1, the total airflow temperature of a low-speed position is obtained, and the low-speed position is located on the upstream side of an inlet of a compressor; s2, the total airflow temperature of an inlet of the gas compressor is obtained, and the total airflow temperature of an outlet of the gas compressor is obtained; s3, the total airflow pressure of an inlet of the gas compressor is obtained, and the total airflow pressure of an outlet of the gas compressor is obtained; s4, obtaining airflow isentropic compression work according to the airflow total pressure at the inlet of the gas compressor, the airflow total pressure at the outlet of the gas compressor and the airflow total temperature at the low-speed position; s5, according to the total temperature of the air flow at the inlet of the air compressor and the total temperature of the air flow at the outlet of the air compressor, the actual consumption compression work of the air flow is obtained; and S6, according to the airflow isentropic compression work and the actual consumption compression work of the airflow, the temperature rise efficiency of the gas compressor is obtained.

Description

Technical Field

[0001] The present invention relates to the technical field of aero-engine compressor test, and particularly relates to a method for obtaining the temperature rise efficiency of a compressor. Background Art

[0002] The isentropic efficiency of a compressor is the ratio of the isentropic compression work of the air flow passing through the compressor to the actual compression work consumed by the air flow, reflecting the economy of the compression component in achieving a certain pressurization capacity. Currently, in the performance test of a compressor, according to different measurement methods of the actual compression work consumed by the air flow, the isentropic efficiency of the compressor can be divided into temperature rise efficiency and torque efficiency. The temperature rise efficiency focuses on measuring the total temperature of the air flow at the inlet and outlet of the compressor by using total temperature probes, and then calculating the actual compression work consumed by the air flow. Compared with the torque efficiency, fewer measurement parameters are required, and it is a method generally adopted in the current industry to evaluate the isentropic efficiency of the compressor. The total temperature of the air flow at the inlet and outlet of the compressor is measured by total temperature probes located at the measurement sections at the inlet and outlet of the compressor. However, there is a reheat effect when using thermocouple total temperature probes to measure the total temperature of the air flow. Since the air flow cannot be effectively stagnated, the measured value of the total temperature of the air flow by the thermocouple total temperature probe is generally lower than the true value of the total temperature of the air flow, forming a velocity error. And as the air flow velocity is greater, the measured value of the total temperature of the air flow is even lower, resulting in a large error in the temperature rise efficiency. Summary of the Invention

[0003] The purpose of the present invention is to provide a method for obtaining the temperature rise efficiency of a compressor to reduce the error of the temperature rise efficiency.

[0004] According to an embodiment of the present invention, the method for obtaining the temperature rise efficiency of a compressor includes step S1. obtaining the total temperature of the air flow at a low-speed position, where the low-speed position is located on the upstream side of the compressor inlet; step S2. obtaining the total temperature of the air flow at the compressor inlet and obtaining the total temperature of the air flow at the compressor outlet; step S3. obtaining the total pressure of the air flow at the compressor inlet and obtaining the total pressure of the air flow at the compressor outlet; step S4. obtaining the isentropic compression work of the air flow according to the total pressure of the air flow at the compressor inlet, the total pressure of the air flow at the compressor outlet, and the total temperature of the air flow at the low-speed position; step S5. obtaining the actual compression work consumed by the air flow according to the total temperature of the air flow at the compressor inlet and the total temperature of the air flow at the compressor outlet; and step S6. obtaining the temperature rise efficiency of the compressor according to the isentropic compression work of the air flow and the actual compression work consumed by the air flow.

[0005] In one or more embodiments, in step S1, the flow velocity of the air flow at the low-speed position is less than or equal to 15 meters per second.

[0006] In one or more embodiments, in step S1, the low-speed position is located in a pressure stabilizing tank.

[0007] In one or more embodiments, step S1 includes measuring the total temperature of the air flow at the low-speed position using a total temperature probe, setting two to four total temperature measurement points, and the total temperature of the air flow at the low-speed position being the arithmetic mean of the values measured at the multiple total temperature measurement points.

[0008] In one or more embodiments, step S2 includes measuring the total temperature of the air flow at the inlet of the compressor using an inlet total temperature probe and measuring the total temperature of the air flow at the outlet of the compressor using an outlet total temperature probe, and the inlet total temperature probe and the outlet total temperature probe being the same.

[0009] In one or more embodiments, step S3 includes measuring the total pressure of the air flow at the inlet of the compressor using an inlet total pressure probe and measuring the total pressure of the air flow at the outlet of the compressor using an outlet total pressure probe.

[0010] In one or more embodiments, steps S2 and S3 include measuring the total temperature and total pressure of the air flow at the inlet of the compressor using an inlet total temperature and total pressure combined probe, and measuring the total temperature and total pressure of the air flow at the outlet of the compressor using an outlet total temperature and total pressure combined probe.

[0011] In one or more embodiments, in step S4, the isentropic compression work of the air flow is T 0 being the total temperature of the air flow at the low-speed position, P in being the total pressure of the air flow at the inlet of the compressor, P ex being the total pressure of the air flow at the outlet of the compressor, and γ being the specific heat ratio.

[0012] In one or more embodiments, in step S5, the actual compression work consumed by the air flow is T ex，g -T in，g T ex，g being the total temperature of the air flow at the outlet of the compressor, and T in，g being the total temperature of the air flow at the inlet of the compressor.

[0013] In one or more embodiments, the method for obtaining the compressor temperature rise efficiency further includes step S7. Obtaining the relative converted speed of the compressor according to the total temperature of the air flow at the low-speed position to control the operating state of the compressor.

[0014] The embodiments of the present invention at least have the following beneficial effects:

[0015] Utilizing the flow field characteristics that the Mach number of the air flow at the inlet of the compressor is greater than that at the outlet of the compressor and the reheat effect of the total temperature probe to cancel the velocity errors of the inlet total temperature probe and the outlet total temperature probe, enabling the measured values of the air flow temperature rise at the inlet and outlet of the compressor to accurately represent the true values of the air flow temperature rise at the inlet and outlet of the compressor, thereby improving the accuracy of the actual compression work consumed by the air flow and reducing the error of the compressor temperature rise efficiency. Brief Description of the Drawings

[0016] The above and other features, properties, and advantages of the present invention will become more apparent from the following description in conjunction with the drawings and embodiments, where:

[0017] Figure 1 is a flowchart of the method for obtaining the compressor temperature rise efficiency;

[0018] Figure 2 is a measurement schematic diagram in the method for obtaining the compressor temperature rise efficiency;

[0019] Figure 3 is the temperature loss characteristic diagram of the total temperature probe;

[0020] Figure 4 is the characteristic diagram of the compressor temperature rise efficiency;

[0021] Reference Signs:

[0022] 1 - Low - speed position;

[0023] 2 - Compressor inlet;

[0024] 3 - Pressure stabilizing tank;

[0025] 4 - Compressor outlet;

[0026] 5 - Compressor inlet measurement section;

[0027] 6 - Compressor outlet measurement section. Detailed Description of the Embodiments

[0028] Now, reference will be made in detail to the embodiments of the present invention, one or more examples of which are shown in the drawings. Each example is provided to explain the present invention, not to limit it. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the scope or spirit thereof. For example, features shown or described as part of one embodiment can be used with another embodiment to yield yet another embodiment. Accordingly, the present invention is intended to cover these modifications and variations that fall within the scope of the appended claims and their equivalents.

[0029] It should be noted that these and subsequent other drawings are only examples, which are not drawn under the condition of equal proportion, and should not be used to limit the actual protection scope required by the present invention.

[0030] For compressors with no inter - stage air extraction or a small amount of air extraction, the simplified theoretical calculation formula for the compressor temperature rise efficiency is as follows:

[0031]

[0032] Among them, η is the temperature rise efficiency of the compressor. γ is the specific heat ratio, dimensionless. π is the pressure ratio of the compressor, which is the ratio of the total pressure P ex of the air flow at the outlet of the compressor to the total pressure P in of the air flow at the inlet of the compressor. T in is the total temperature of the air flow at the inlet of the compressor, with the unit K (Kelvin). T ex is the total temperature of the air flow at the outlet of the compressor, with the unit K (Kelvin). is the isentropic compression work of the air flow. T ex -T in is the actual compression work consumed by the air flow.

[0033] The total temperature T in of the air flow at the inlet of the compressor and the total temperature T ex of the air flow at the outlet of the compressor are measured by total temperature probes located at the measurement sections at the inlet and outlet of the compressor. The total temperature probes measure the measured value T in,g of the total temperature of the air flow at the inlet of the compressor and the measured value T ex,g of the total temperature of the air flow at the outlet of the compressor. The measured value T in,g of the total temperature of the air flow at the inlet of the compressor is used to represent the total temperature T in of the air flow at the inlet of the compressor, and the measured value T ex,g of the total temperature of the air flow at the outlet of the compressor is used to represent the total temperature T ex of the air flow at the outlet of the compressor. Then, the calculation formula for the temperature rise efficiency of the compressor is as follows:

[0034]

[0035] Among them, the unit of T in,g is K (Kelvin). The unit of T ex,g is K (Kelvin). The meanings of the remaining parameters are the same as above.

[0036] However, when using a thermocouple total temperature probe to measure the total temperature of the air flow, due to the ineffective stagnation of the air flow, the measured values T in,g and T ex,g of the total temperature of the air flow measured by the thermocouple total temperature probe are generally lower than the true values T in and T ex of the total temperature of the air flow, forming a velocity error. Moreover, the greater the air flow velocity, the lower the measured value of the total temperature of the air flow, resulting in a large error in the temperature rise efficiency.

[0037] In addition, during the test process of obtaining the temperature rise efficiency of the compressor, the working state of the compressor is controlled according to the relative conversion speed of the compressor. The relative conversion speed is calculated from the measured value T in,g of the total temperature of the air flow at the inlet of the compressor. Since the measured value T in,g of the total temperature of the air flow at the inlet of the compressor is lower than the true value T in of the total temperature of the air flow, the relative conversion speed is inaccurate, which in turn causes the working state of the compressor to deviate.

[0038] To reduce the error of the temperature rise efficiency, the total temperature data correction method is used to correct the total temperature T of the air flow at the compressor inlet in and the total temperature T of the air flow at the compressor outlet ex . The total temperature data correction method is to perform a blowing calibration on the inlet total temperature probe and the outlet total temperature probe before measuring the compressor, obtain the variation curve of the total temperature recovery coefficient r with the air flow Mach number Ma, and during the test process of obtaining the compressor temperature rise efficiency, the measured values T of the air flow total temperature are corrected in real time in,g 、T ex,g to obtain the corresponding corrected values of the air flow total temperature Furthermore, the compressor temperature rise efficiency is calculated. The formula for the corrected compressor temperature rise efficiency is as follows:

[0039]

[0040] where is the corrected value of the total temperature of the air flow at the compressor inlet, is the corrected value of the total temperature of the air flow at the compressor outlet, is the correction coefficient of the total temperature of the air flow at the compressor inlet, is the correction coefficient of the total temperature of the air flow at the compressor outlet, and the meanings of other parameters are the same as above.

[0041] The correction coefficient is related to the air flow Mach number Ma at the cross-section where the air flow total temperature is measured, the total temperature recovery coefficient r or the temperature loss coefficient ω of the total temperature probe. The calculation formula is as follows:

[0042]

[0043] The total temperature data correction method uses the corrected value of the total temperature of the air flow at the compressor inlet and the corrected value of the total temperature of the air flow at the compressor outlet to represent the total temperature T of the air flow at the compressor inlet in and the total temperature T of the air flow at the compressor outlet ex . It involves the blowing calibration and data correction of the total temperature probe, and the workload is relatively large. In addition, it is necessary to obtain the air flow Mach number Ma at the cross-section where the total temperature probe is measured through the total pressure and static pressure probe. The damage of the total pressure and static pressure measurement points during the test process of obtaining the compressor temperature rise efficiency will affect the data correction. The relative conversion speed used for the compressor speed control needs to be calculated according to the corrected value of the total temperature of the air flow at the compressor inlet . Any abnormality in the total pressure, static pressure or total temperature measurement points at the compressor inlet will cause a large deviation in the calculation of the relative conversion speed, seriously affecting the test safety.

[0044] Such as Figure 1As shown, the method for obtaining the compressor temperature rise efficiency includes step S1. Obtain the total temperature of the air flow at the low-speed position 1, and the low-speed position 1 is located upstream of the compressor inlet 2. The total temperature probe can be used to measure the total temperature of the air flow at the low-speed position 1. As Figure 2 shown, the low-speed position 1 is the measurement section, located upstream of the compressor inlet 2. The air flow velocity at the low-speed position 1 is low, and the dynamic temperature of the air flow can be almost ignored, so that the total temperature probe has almost no velocity error, and further, the total temperature of the air flow at the low-speed position measured by the total temperature probe at the low-speed position 1 is T 0 accurately represents the true value T of the total temperature of the air flow at the compressor inlet in . The standard for selecting the low-speed position 1 can be that the air flow velocity at the low-speed position 1 is less than or equal to 15 m / s. The low-speed position 1 can be selected in the pressure stabilizing box 3. The total temperature probe can be used to set two to four total temperature measurement points at the low-speed position 1, and the total temperature T of the air flow at the low-speed position 0 is the arithmetic mean of the measured values of multiple total temperature measurement points.

[0045] As Figure 1 shown, the method for obtaining the compressor temperature rise efficiency further includes step S2. Obtain the total temperature of the air flow at the compressor inlet 2, and obtain the total temperature of the air flow at the compressor outlet 4. As Figure 2 shown, the inlet total temperature probe can be used to measure the total temperature of the air flow at the compressor inlet 2 at the compressor inlet measurement section 5 to obtain the measured value T of the total temperature of the air flow at the compressor inlet in,g , and the outlet total temperature probe can be used to measure the total temperature of the air flow at the compressor outlet 4 at the compressor outlet measurement section 6 to obtain the measured value T of the total temperature of the air flow at the compressor outlet ex,g . The inlet total temperature probe and the outlet total temperature probe are the same, and are consistent in structure and thermocouple type, so that the inlet total temperature probe and the outlet total temperature probe have similar total temperature recovery coefficients r and temperature loss coefficients ω. The number of measurement points of the inlet total temperature probe and the outlet total temperature probe and the average calculation method of the measurement point data can refer to the aviation industry standard HB7115 "Aerodynamic Performance Test Method for Compressors of Aero Gas Turbine Engines".

[0046] As Figure 1 shown, the method for obtaining the compressor temperature rise efficiency further includes step S3. Obtain the total pressure of the air flow at the compressor inlet 2, and obtain the total pressure of the air flow at the compressor outlet 4. As Figure 2 shown, the inlet total pressure probe can be used to measure the total pressure of the air flow at the compressor inlet 2 at the compressor inlet measurement section 5 to obtain the total pressure P of the air flow at the compressor inlet in , and the outlet total pressure probe can be used to measure the total pressure of the air flow at the compressor outlet 4 at the compressor outlet measurement section 6 to obtain the total pressure P of the air flow at the compressor outlet exThe compressor inlet measurement section 5 should be arranged at a position with a relatively high air velocity in the air flow at the compressor inlet 2, and the compressor inlet measurement section 5 should be as close as possible to the compressor inlet 2 towards the rear side. The number of measurement points of the inlet total pressure probe and the outlet total pressure probe, as well as the average calculation method of the measurement point data, can refer to the aviation industry standard HB7115 "Test Method for Aerodynamic Performance of Compressors in Aero Gas Turbine Engines".

[0047] In steps S2 and S3, an inlet total temperature and pressure combined probe can also be used to measure the total air temperature and total air pressure at the compressor inlet 2 at the compressor inlet measurement section 5, and obtain the measured value T of the total air temperature at the compressor inlet in,g and the measured value P of the total air pressure at the compressor inlet in . An outlet total temperature and pressure combined probe is used to measure the total air temperature and total air pressure of the air flow at the compressor outlet 4 at the compressor outlet measurement section 6, and obtain the measured value T of the total air temperature at the compressor outlet ex,g and the measured value P of the total air pressure at the compressor outlet ex .

[0048] As Figure 1 shown, the method for obtaining the compressor temperature rise efficiency further includes step S4. Obtain the isentropic compression work of the air flow according to the total air pressure at the compressor inlet 2, the total air pressure at the compressor outlet 4, and the total air temperature at the low-speed position 1. The calculation formula for the isentropic compression work of the air flow can be:

[0049]

[0050] where, T 0 is the total air temperature at the low-speed position, P in is the total air pressure at the compressor inlet, P ex is the total air pressure at the compressor outlet, and γ is the specific heat ratio.

[0051] As mentioned above, the total air temperature T 0 at the low-speed position accurately represents the true value T in of the total air temperature at the compressor inlet, thereby improving the accuracy of the isentropic compression work of the air flow and reducing errors.

[0052] As Figure 1 shown, the method for obtaining the compressor temperature rise efficiency further includes step S5. Obtain the actual compression work consumed by the air flow according to the total air temperature at the compressor inlet 2 and the total air temperature at the compressor outlet 4. The calculation formula for the actual compression work consumed by the air flow can be:

[0053] T ex,g - T in,g (Equation 6)

[0054] where, T ex,g is the measured value of the total air temperature at the compressor outlet, and T in,g is the measured value of the total air temperature at the compressor inlet.

[0055] Due to the rewarming effect of the total temperature probe, there are velocity errors in both the inlet total temperature probe and the outlet total temperature probe, resulting in the measured total temperature of the inlet air flow of the compressor, T in,g being lower than the true total temperature of the inlet air flow of the compressor, T in , and the measured total temperature of the outlet air flow of the compressor, T ex,g being lower than the true total temperature of the outlet air flow of the compressor, T ex . Referring to Equations 3 and 4, the true temperature rise of the air flow at the inlet and outlet of the compressor, T ex -T in and the measured temperature rise of the air flow at the inlet and outlet of the compressor, T ex,g -T in,g are related as follows:

[0056]

[0057] where ω ex is the temperature loss coefficient of the outlet total temperature probe, ω in is the temperature loss coefficient of the inlet total temperature probe, and the meanings of other parameters are the same as above.

[0058] Utilizing the flow field characteristic that the Mach number of the air flow at the inlet of the compressor, Ma, is greater than that at the outlet of the compressor, Ma, and the rewarming effect of the total temperature probe to cancel the velocity errors of the inlet total temperature probe and the outlet total temperature probe, such that the measured temperature rise of the air flow at the inlet and outlet of the compressor, T ex,g -T in,g accurately represents the true temperature rise of the air flow at the inlet and outlet of the compressor, T ex -T in . When the ratio of the temperature loss coefficient of the inlet total temperature probe to the temperature loss coefficient of the outlet total temperature probe, ω in / ω ex makes T ex / T in ≈T ex,g / T in,g , the temperature rise ratio of the compressor, T ex -T in ≈T ex,g -T in,g , that is, there is no need to correct the measured temperature rise of the air flow at the inlet and outlet of the compressor. As Figure 3 shown, for the same total temperature probe, the temperature loss coefficient ω is related to the Mach number of the air flow Ma. When the rotational speed of the compressor is low, the temperature rise of the air flow at the inlet and outlet is small, the Mach number of the air flow at the outlet of the compressor, Ma, is close to the Mach number of the air flow at the inlet of the compressor, Ma, and the temperature loss coefficient ω ex of the outlet total temperature probe is close to the temperature loss coefficient ω in of the inlet total temperature probe. At this time, the temperature rise ratio of the compressor is close to 1, that is, T ex,g ω ex -T in,g ωin ≈0. As the compressor speed increases, the compressor temperature rise ratio gradually increases. The Mach number Ma of the airflow at the compressor inlet increases significantly, while the Mach number Ma of the airflow at the compressor outlet increases slightly. At this time, the temperature loss coefficient ω of the inlet total temperature probe in is significantly greater than the temperature loss coefficient ω of the outlet total temperature probe ex , and there is also T ex,g ω ex -T in,g ω in ≈0. It can be seen that the measured values of the airflow temperature rise at the compressor inlet and outlet T ex,g -T in,g can accurately represent the true values of the airflow temperature rise at the compressor inlet and outlet T ex -T in , thereby improving the accuracy of the actual compression work consumed by the airflow, reducing errors, and avoiding the correction of total temperature data, which is more convenient.

[0059] Using the reverse cascade method, short-circuiting the negative poles of the measuring points corresponding to the inlet total temperature probe and the outlet total temperature probe to directly obtain the airflow temperature rise at the compressor inlet and outlet requires the same number of total temperature measuring points for the inlet total temperature probe and the outlet total temperature probe, which is likely to cause uneven airflow at the compressor inlet 2, affecting the test process of obtaining the compressor temperature rise efficiency, and the total temperature measurement value T of the airflow at the compressor inlet cannot be obtained in,g and the total temperature measurement value T of the airflow at the compressor outlet ex,g . Measuring the total temperature measurement value T of the airflow at the compressor inlet in,g and the total temperature measurement value T of the airflow at the compressor outlet ex,g avoids the above problems.

[0060] As Figure 1 shown, the method for obtaining the compressor temperature rise efficiency further includes step S6. Obtaining the compressor temperature rise efficiency according to the isentropic compression work of the airflow and the actual compression work consumed by the airflow. The compressor temperature rise efficiency is the ratio of the isentropic compression work of the airflow to the actual compression work consumed by the airflow. According to the above calculation formulas for the isentropic compression work of the airflow and the actual compression work consumed by the airflow, the calculation formula for the compressor temperature rise efficiency can be:

[0061]

[0062] The parameter meanings are the same as above.

[0063] As Figure 1 shown, the method for obtaining the compressor temperature rise efficiency may further include step S7. Obtaining the relative conversion speed of the compressor according to the total temperature of the airflow at the low-speed position 1 to control the working state of the compressor. During the test process of obtaining the compressor temperature rise efficiency, controlling the working state of the compressor according to the relative conversion speed of the compressor, and the relative conversion speed is determined by the total temperature T of the airflow at the low-speed position 0It is calculated that due to the total temperature T of the air flow at the low-speed position 0 accurately represents the true value T of the total temperature of the air flow at the compressor inlet in , making the relative converted speed accurate, and further making the control of the working state of the compressor accurate. The converted flow rate at the compressor inlet can also be calculated based on the total temperature T of the air flow at the low-speed position 0 .

[0064] As Figure 4 shown, compared with the compressor temperature rise efficiency obtained by the original method (Equation 2), after adopting this method (Equation 8), the temperature rise efficiency is increased by about 0.43% at the 96% design speed, the converted flow rate is increased by about 0.25%, the temperature rise efficiency is increased by about 0.52% at the 98% design speed, and the converted flow rate is increased by about 0.32%.

[0065] The method for obtaining the compressor temperature rise efficiency of the present invention is applicable not only to the compressor tests with low pressure ratio and small temperature rise of the air flow at the compressor inlet and outlet, but also to the high-load multi-stage compressor tests.

[0066] Although the present invention is disclosed as above by way of examples, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications without departing from the spirit and scope of the present invention.

Claims

1. A method for obtaining compressor temperature rise efficiency, characterized in that include: Step S1. Obtaining the total temperature of the airflow at a low speed position, wherein the low speed position is located at the upstream side of the compressor inlet; Step S2. Obtaining the total temperature of the airflow at the compressor inlet and the total temperature of the airflow at the compressor outlet; Step S3. Obtaining the total airflow pressure at the compressor inlet and the total airflow pressure at the compressor outlet; Step S4. Obtaining the isentropic compression work of the airflow according to the total airflow pressure at the compressor inlet, the total airflow pressure at the compressor outlet, and the total airflow temperature at the low-speed position; Step S5. Obtaining the actual compression work consumed by the airflow according to the total airflow temperature at the compressor inlet and the total airflow temperature at the compressor outlet; as well as Step S6. Obtain the compressor temperature rise efficiency according to the isentropic compression work of the airflow and the actual compression work consumed by the airflow.

2. The method for obtaining compressor temperature rise efficiency according to claim 1, characterized in that: In step S1, the velocity of the airflow at the low-speed position is less than or equal to fifteen meters per second.

3. The method for obtaining compressor temperature rise efficiency according to claim 1, characterized in that: In the step S1, the low speed position is located in the surge tank.

4. The method for obtaining compressor temperature rise efficiency according to claim 1, characterized in that: The step S1 includes using a total temperature probe to measure the total temperature of the airflow at the low speed position, setting two to four total temperature measuring points, and the total temperature of the airflow at the low speed position is the arithmetic mean value measured by the multiple total temperature measuring points.

5. The method for obtaining compressor temperature rise efficiency according to claim 1, characterized in that: The step S2 includes using an inlet total temperature probe to measure the total temperature of the airflow at the compressor inlet, and using an outlet total temperature probe to measure the total temperature of the airflow at the compressor outlet, wherein the inlet total temperature probe is the same as the outlet total temperature probe.

6. The method for obtaining compressor temperature rise efficiency according to claim 1, characterized in that: The step S3 includes measuring the total pressure of the airflow at the compressor inlet using an inlet total pressure probe, and measuring the total pressure of the airflow at the compressor outlet using an outlet total pressure probe.

7. The method for obtaining compressor temperature rise efficiency according to claim 1, characterized in that: The steps S2 and S3 include using an inlet total temperature and total pressure composite probe to measure the total airflow temperature and total airflow pressure at the compressor inlet, and using an outlet total temperature and total pressure composite probe to measure the total airflow temperature and total airflow pressure at the compressor outlet.

8. The method for obtaining compressor temperature rise efficiency according to claim 1, characterized in that: In step S4, the isentropic compression work of the airflow is T0 is the total airflow temperature at the low speed position, P in is the total airflow pressure at the compressor inlet, P ex is the total airflow pressure at the compressor outlet, and γ is the specific heat ratio.

9. The method for obtaining compressor temperature rise efficiency according to claim 1, characterized in that: In step S5, the actual compression work consumed by the airflow is T ex,g -T in,g , T ex,g is the total temperature of the airflow at the compressor outlet, T in,g is the total temperature of the air flow at the compressor inlet.

10. The method for obtaining compressor temperature rise efficiency according to claim 1, characterized in that Also includes: Step S7. According to the total temperature of the airflow at the low-speed position, the relative converted speed of the compressor is obtained to control the working state of the compressor.

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