CN115163536A - Method and device for evaluating margin of compressor under complete state of aircraft engine - Google Patents

Method and device for evaluating margin of compressor under complete state of aircraft engine Download PDF

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CN115163536A
CN115163536A CN202210902976.2A CN202210902976A CN115163536A CN 115163536 A CN115163536 A CN 115163536A CN 202210902976 A CN202210902976 A CN 202210902976A CN 115163536 A CN115163536 A CN 115163536A
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compressor
point
margin
pressure ratio
surge
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吉思环
施磊
王军
李焦宇
郭海红
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AECC Shenyang Engine Research Institute
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AECC Shenyang Engine Research Institute
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D27/00—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
    • F04D27/001—Testing thereof; Determination or simulation of flow characteristics; Stall or surge detection, e.g. condition monitoring
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T90/00—Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation

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Abstract

The application belongs to the technical field of engine tests, and particularly relates to a method and a device for evaluating the margin of a compressor under the complete state of an aero-engine. The method comprises the steps of S1, obtaining the characteristics of the air compressor under the current geometric angle, and determining a surge boundary according to the characteristics of the air compressor; s2, calculating the converted rotating speed of the air compressor; s3, calculating the pressure ratio of the air compressor at the working point; s4, determining the converted flow of the inlet of the gas compressor at the working point based on the characteristics of the gas compressor under the current geometric angle; s5, interpolating a compressor pressure ratio at a surge point and a compressor flow at the surge point according to the converted rotating speed of the compressor and the surge boundary; and S6, calculating the margin of the compressor. The method and the device solve the problem that the margin evaluation cannot be carried out due to the fact that the air flow measurement cannot be carried out, and meanwhile, the workload and the resource waste caused by maintenance/replacement of parts which all affect the margin can be effectively avoided.

Description

Method and device for evaluating margin of compressor under complete state of aircraft engine
Technical Field
The application belongs to the technical field of engine tests, and particularly relates to a method and a device for evaluating the margin of a compressor under the complete state of an aero-engine.
Background
The stability margin evaluation of the double-shaft turbofan engine mainly comprises fan margin evaluation and compressor margin evaluation, the fan margin can be used for carrying out air flow and inlet and outlet pressure measurement evaluation under the complete machine state of a ground rack, but for the compressor, the compressor is positioned in an inner duct of the engine and cannot be used for measuring the inlet air flow under the complete machine state through test modification.
Generally, in order to ensure the compressor margin when an engine leaves a factory, a 'surge-forcing test' is carried out, namely, the margin is considered to be sufficient if the engine does not surge by giving a large oil supply amount. Although the method can screen the margin of the compressor of the engine which leaves a factory, only qualified products and unqualified products can be screened, the specific value of the margin of the compressor cannot be identified, and particularly the specific difference of the margin of the compressor of the unqualified engine cannot be given. Therefore, when a failure occurs, all parts affecting the margin need to be replaced or repaired (so as not to have a margin still insufficient), which results in a drastic increase in the repair work load and cost.
How to determine the inlet air flow of the compressor in the complete machine state through measurable parameters so as to determine the surge margin of the compressor in the complete machine state is an urgent problem to be solved.
Disclosure of Invention
In order to solve one of the problems, the application provides a method and a device for evaluating the margin of the compressor under the complete machine state of the aircraft engine, and the specific value of the margin of the compressor under the current geometric angle is calculated according to the characteristics of the compressor under different existing angles.
The application provides in a first aspect a method for evaluating the margin of an air compressor under the complete state of an aircraft engine, which mainly comprises the following steps:
s1, obtaining the characteristics of the air compressor under the current geometric angle, wherein the characteristics of the air compressor represent the converted flow W of an inlet of the air compressor r Speed n converted from compressor r Pressure ratio pi of gas compressor c Determining a surge boundary according to the characteristics of the compressor;
step S2, by measuring pressureCalculating the physical rotation speed of the gas compressor and the inlet temperature of the gas compressor, and calculating the converted rotation speed n of the gas compressor r ；
S3, calculating the pressure ratio pi of the air compressor at the working point according to the measured inlet and outlet pressures of the air compressor c operating point ；
S4, determining the compressor inlet conversion flow W at the working point based on the compressor characteristics under the current geometric angle r operating point ；
S5, converting the rotating speed n according to the air compressor r Interpolating a compressor pressure ratio pi at a surge point with the surge boundary c dyspnea point And compressor flow W at surge point Gamma point of dyspnea ；
S6, based on the pressure ratio pi of the air compressor at the working point c operating point Gas compressor inlet conversion flow W at working point r operating point Pressure ratio pi of air compressor at surge point c asthma point And compressor flow W at surge point 'gamma' Chuan Dian And calculating the margin of the compressor.
Preferably, in step S1, the obtaining of the compressor characteristic under the current geometric angle includes:
and interpolating the characteristics of the compressor at the current geometric angle according to the characteristics of the compressor at different geometric angles.
Preferably, in step S2, the compressor reduced rotation speed n is calculated by the following formula r ：
Figure BDA0003771543980000021
Wherein n is the physical rotating speed of the compressor, T d For design point compressor inlet total temperature, T in The compressor inlet temperature.
Preferably, in step S3, the compressor pressure ratio pi at the working point is calculated c operating point The method comprises the following steps:
Figure BDA0003771543980000022
wherein, P in Is the compressor inlet pressure, P out The compressor outlet pressure.
Preferably, in step S6, the calculating the compressor margin SM includes:
Figure BDA0003771543980000023
the application second aspect provides a compressor margin evaluation device under aeroengine complete machine state, mainly includes:
the air compressor characteristic obtaining module is used for obtaining the air compressor characteristic under the current geometric angle, and the air compressor characteristic represents the converted flow W of the air compressor inlet r Speed n converted from compressor r Pressure ratio pi of gas compressor c Determining a surge boundary according to the characteristics of the compressor;
the gas compressor conversion rotating speed calculation module is used for calculating the gas compressor conversion rotating speed n by measuring the physical rotating speed of the gas compressor and the inlet temperature of the gas compressor r ；
The compressor pressure ratio calculation module is used for calculating the compressor pressure ratio pi at the working point according to the measured inlet and outlet pressures of the compressor c operating point ；
A compressor inlet conversion flow acquisition module at the working point for determining the compressor inlet conversion flow W at the working point based on the compressor characteristics under the current geometric angle r operating point ；
A compressor flow and pressure ratio obtaining module at the surge point for obtaining the conversion speed n of the compressor r Interpolating a compressor pressure ratio pi at a surge point with the surge boundary c asthma point And compressor flow W at surge point 'gamma' Chuan Dian ；
A compressor margin calculation module for calculating the compressor pressure ratio pi based on the working point c operating point Gas compressor inlet conversion flow W at working point r operating point Pressure ratio pi of air compressor at surge point c asthma point And compressor flow W at surge point 'gamma' Chuan Dian And calculating the margin of the compressor.
Preferably, the compressor characteristic acquiring module includes an interpolation unit, which is used for interpolating the compressor characteristic at the current geometric angle according to the compressor characteristics at different geometric angles.
Preferably, in the compressor converted rotational speed calculation module, the compressor converted rotational speed n is calculated by the following formula r ：
Figure BDA0003771543980000031
Wherein n is the physical rotating speed of the compressor, T d For design point compressor inlet total temperature, T in The compressor inlet temperature.
Preferably, in the compressor pressure ratio calculating module, the compressor pressure ratio pi at the working point is calculated c operating point The method comprises the following steps:
Figure BDA0003771543980000032
wherein, P in Is the compressor inlet pressure, P out The compressor outlet pressure.
Preferably, the calculating the compressor margin SM by the compressor margin calculating module includes:
Figure BDA0003771543980000033
the method and the device not only solve the problem that margin evaluation cannot be carried out due to the fact that air flow measurement cannot be carried out, but also can be used as a compressor margin evaluation method when the engine leaves a factory to guide accurate formulation of engine troubleshooting measures with insufficient compressor margin, and can effectively avoid workload and resource waste caused by maintenance/replacement of all parts influencing the margin.
Drawings
FIG. 1 is a flowchart of a preferred embodiment of a method for evaluating a margin of a compressor under a complete machine state of an aircraft engine according to the present application;
fig. 2 is a compressor map.
Detailed Description
In order to make the implementation objects, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described in more detail below with reference to the accompanying drawings in the embodiments of the present application. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are implementations that are part of this application and not all implementations. The embodiments described below with reference to the drawings are exemplary and intended to be used for explaining the present application, and should not be construed as limiting the present application. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments in the present application without making any creative effort belong to the protection scope of the present application. Embodiments of the present application will be described in detail below with reference to the drawings.
The application provides a compressor margin evaluation method under the complete machine state of an aircraft engine, as shown in fig. 1, mainly includes:
s1, obtaining the characteristics of the air compressor under the current geometric angle, wherein the characteristics of the air compressor represent the converted flow W of an inlet of the air compressor r Speed n converted from compressor r Pressure ratio pi of gas compressor c Determining a surge boundary according to the characteristics of the compressor;
s2, calculating the converted rotating speed n of the gas compressor by measuring the physical rotating speed of the gas compressor and the inlet temperature of the gas compressor r ；
S3, calculating the pressure ratio pi of the air compressor at the working point according to the measured inlet and outlet pressures of the air compressor c operating point ；
S4, determining the compressor inlet conversion flow W at the working point based on the compressor characteristics under the current geometric angle r operating point ；
S5, converting the rotating speed n according to the air compressor r Interpolating a compressor pressure ratio pi at a surge point with the surge boundary c asthma point And compressor flow at surge pointW Gamma point of dyspnea ；
S6, based on the pressure ratio pi of the air compressor at the working point c operating point Gas compressor inlet conversion flow W at working point r operating point Pressure ratio pi of air compressor at surge point c asthma point And compressor flow W at surge point Gamma point of dyspnea And calculating the margin of the compressor.
In some alternative embodiments, the step S1 of obtaining the compressor characteristic at the current geometric angle includes:
and interpolating the characteristics of the compressor at the current geometric angle according to the characteristics of the compressor at different geometric angles.
In this embodiment, referring to fig. 2, the compressor characteristics W at different geometric angles are obtained r ＝f i (n r ,π c ) I =1,2, n (with surge margin (W) Gamma point of dyspnea ，π c asthma point )＝f i boundary (n r ) Interpolation of the compressor characteristic W at the current geometric angle) r ＝f At present (n r ,π c ) (wherein the surge boundary is (W) 'gamma' Chuan Dian ，π c asthma point )＝f Current boundary (n r )). The dashed line in fig. 2 is the surge margin.
In some alternative embodiments, in step S2, the compressor reduced speed n is calculated by the following formula r ：
Figure BDA0003771543980000051
Wherein n is the physical rotating speed of the compressor, T d For the design point of the total inlet temperature T of the compressor in The compressor inlet temperature.
In this embodiment, the total temperature T is increased at the compressor inlet in Thereby calculating the conversion speed n of the compressor r 。
In some alternative embodiments, in step S3, the compressor pressure ratio pi at the operating point is calculated c operating point The method comprises the following steps:
Figure BDA0003771543980000052
wherein, P in Is the compressor inlet pressure, P out The compressor outlet pressure.
In some alternative embodiments, the calculating of the compressor margin SM in step S6 includes:
Figure BDA0003771543980000053
the second aspect of the present application provides a device for evaluating the margin of a compressor in the complete state of an aircraft engine corresponding to the above method, which mainly comprises:
the compressor characteristic acquisition module is used for acquiring the characteristics of the compressor under the current geometric angle, and the characteristics of the compressor represent the inlet converted flow W of the compressor r Speed n converted from compressor r Pressure ratio pi of gas compressor c Determining a surge boundary according to the characteristics of the compressor;
the gas compressor conversion rotating speed calculation module is used for calculating the gas compressor conversion rotating speed n by measuring the physical rotating speed of the gas compressor and the inlet temperature of the gas compressor r ；
The compressor pressure ratio calculation module is used for calculating the compressor pressure ratio pi at the working point according to the measured inlet and outlet pressures of the compressor c operating point ；
A compressor inlet conversion flow acquisition module at the working point for determining the compressor inlet conversion flow W at the working point based on the compressor characteristics under the current geometric angle r operating point ；
A compressor flow and pressure ratio obtaining module at the surge point for converting the rotating speed n according to the compressor r Interpolating a compressor pressure ratio pi at a surge point with the surge boundary c asthma point And compressor flow W at surge point Gamma point of dyspnea ；
A compressor margin calculation module for calculating the compressor pressure ratio pi based on the working point c operating point Gas compressor inlet conversion at working pointFlow rate W r operating point Compressor pressure ratio pi at surge point c asthma point And compressor flow W at surge point Gamma point of dyspnea And calculating the margin of the compressor.
In some optional embodiments, the compressor characteristic obtaining module includes an interpolation unit, configured to interpolate the compressor characteristic at the current geometric angle according to the compressor characteristic at different geometric angles.
In some optional embodiments, in the compressor reduced rotation speed calculation module, the compressor reduced rotation speed n is calculated by the following formula r ：
Figure BDA0003771543980000061
Wherein n is the physical rotating speed of the compressor, T d For design point compressor inlet total temperature, T in The compressor inlet temperature.
In some optional embodiments, in the compressor pressure ratio calculation module, a compressor pressure ratio pi at an operating point is calculated c operating point The method comprises the following steps:
Figure BDA0003771543980000062
wherein, P in Is the compressor inlet pressure, P out The compressor outlet pressure.
In some optional embodiments, the compressor margin calculation module, calculating the compressor margin SM, includes:
Figure BDA0003771543980000063
the method and the device not only solve the problem that the margin evaluation cannot be carried out due to the fact that the air flow measurement cannot be carried out, but also can be used as a compressor margin evaluation method when the engine leaves a factory to guide accurate formulation of engine troubleshooting measures with insufficient margin of the compressor, namely, part of components can be maintained, and workload and resource waste caused by maintenance/replacement of all components influencing the margin can be effectively avoided.
Although the present application has been described in detail with respect to the general description and specific embodiments, it will be apparent to those skilled in the art that certain modifications or improvements may be made based on the present application. Accordingly, such modifications and improvements are intended to be within the scope of this invention as claimed.

Claims (10)

1. A method for evaluating the margin of a compressor under the complete state of an aircraft engine is characterized by comprising the following steps:
s1, obtaining the characteristics of the air compressor under the current geometric angle, wherein the characteristics of the air compressor represent the inlet converted flow W of the air compressor r Speed n converted from compressor r Pressure ratio pi of gas compressor c Determining a surge boundary according to the characteristics of the compressor;
s2, calculating the converted rotating speed n of the gas compressor by measuring the physical rotating speed of the gas compressor and the inlet temperature of the gas compressor r ；
S3, calculating the pressure ratio pi of the air compressor at the working point according to the measured inlet and outlet pressures of the air compressor c operating point ；
S4, determining the compressor inlet conversion flow W at the working point based on the compressor characteristics under the current geometric angle r operating point ；
S5, converting the rotating speed n according to the air compressor r Interpolating a compressor pressure ratio pi at a surge point with the surge boundary c asthma point And compressor flow W at surge point Gamma point of dyspnea ；
S6, based on the pressure ratio pi of the air compressor at the working point c operating point Gas compressor inlet conversion flow W at working point r operating point Pressure ratio pi of air compressor at surge point c asthma point And compressor flow W at surge point Gamma point of dyspnea And calculating the margin of the compressor.
2. The method for evaluating the margin of the compressor under the complete machine state of the aircraft engine according to claim 1, wherein the step S1 of obtaining the characteristics of the compressor under the current geometric angle comprises the following steps:
and interpolating the characteristics of the compressor at the current geometric angle according to the characteristics of the compressor at different geometric angles.
3. The method for evaluating the margin of the compressor under the complete state of the aircraft engine as claimed in claim 1, wherein in step S2, the converted rotating speed n of the compressor is calculated by the following formula r ：
Figure FDA0003771543970000011
Wherein n is the physical rotating speed of the compressor, T d For the design point of the total inlet temperature T of the compressor in Is the compressor inlet temperature.
4. The method for evaluating the margin of the compressor under the complete machine state of the aircraft engine according to claim 1, wherein in the step S3, the compressor pressure ratio pi at the working point is calculated c operating point The method comprises the following steps:
Figure FDA0003771543970000012
wherein, P in Is the compressor inlet pressure, P out The compressor outlet pressure.
5. The method for evaluating the compressor margin under the complete aircraft engine state according to claim 1, wherein the step S6 of calculating the compressor margin SM comprises:
Figure FDA0003771543970000021
6. the utility model provides a compressor margin evaluation device under aeroengine complete machine state which characterized in that includes:
the air compressor characteristic obtaining module is used for obtaining the air compressor characteristic under the current geometric angle, and the air compressor characteristic represents the converted flow W of the air compressor inlet r Speed n converted from compressor r Pressure ratio pi of gas compressor c Determining a surge boundary according to the characteristics of the compressor;
the gas compressor conversion rotating speed calculation module is used for calculating the gas compressor conversion rotating speed n by measuring the physical rotating speed of the gas compressor and the inlet temperature of the gas compressor r ；
The compressor pressure ratio calculation module is used for calculating the compressor pressure ratio pi at the working point according to the measured inlet and outlet pressures of the compressor c operating point ；
A compressor inlet conversion flow acquisition module at the working point for determining the compressor inlet conversion flow W at the working point based on the compressor characteristics under the current geometric angle r operating point ；
A compressor flow and pressure ratio obtaining module at the surge point for converting the rotating speed n according to the compressor r Interpolating a compressor pressure ratio pi at a surge point with the surge boundary c dyspnea point And compressor flow W at surge point Gamma point of dyspnea ；
A compressor margin calculation module for calculating the compressor pressure ratio pi based on the working point c operating point Gas compressor inlet conversion flow W at working point r operating point Compressor pressure ratio pi at surge point c asthma point And compressor flow W at surge point 'gamma' Chuan Dian And calculating the margin of the compressor.
7. The device for evaluating the margin of the compressor under the complete machine state of the aircraft engine as claimed in claim 6, wherein the compressor characteristic acquisition module comprises an interpolation unit, and is used for interpolating the compressor characteristic under the current geometric angle according to the compressor characteristics under different geometric angles.
8. The aircraft of claim 6The device for evaluating the margin of the compressor under the condition of the whole engine is characterized in that in the calculation module of the converted rotating speed of the compressor, the converted rotating speed n of the compressor is calculated by the following formula r ：
Figure FDA0003771543970000022
Wherein n is the physical rotating speed of the compressor, T d For the design point of the total inlet temperature T of the compressor in The compressor inlet temperature.
9. The apparatus for evaluating the margin of a compressor in the complete machine state of an aircraft engine according to claim 6, wherein the compressor pressure ratio calculating module calculates the compressor pressure ratio pi at the working point c operating point The method comprises the following steps:
Figure FDA0003771543970000031
wherein, P in Is the compressor inlet pressure, P out The compressor outlet pressure.
10. The apparatus for evaluating the margin of the compressor under the complete machine condition of the aircraft engine according to claim 6, wherein the compressor margin calculating module for calculating the compressor margin SM comprises:
Figure FDA0003771543970000032
CN202210902976.2A 2022-07-29 2022-07-29 Method and device for evaluating margin of compressor under complete state of aircraft engine Pending CN115163536A (en)

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CN202210902976.2A CN115163536A (en) 2022-07-29 2022-07-29 Method and device for evaluating margin of compressor under complete state of aircraft engine

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