A method for determining a speed and temperature limit value for an aero gas turbine shaft engine

Abstract

The application belongs to the technical field of engines, and particularly relates to a method for determining the rotation speed and temperature limit value of an aero gas turbine shaft engine, which comprises the following steps: determining the design state rotation speed N gd and temperature T45 d ; determining the limit value A considering the demand of an airplane; determining the limit value B considering the performance attenuation of the engine; strength checking; ground life test; and high-altitude performance test. In the process of determining the rotation speed and temperature limit value of the engine, the power demand in the whole working envelope of the airplane and the performance attenuation factor of the engine in the use process are considered simultaneously, the flight task interruption or limitation caused by insufficient power is avoided, the utilization rate of the engine is improved, the service life of the engine is prolonged, and the frequency of component replacement and maintenance is reduced.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of engine, and particularly relates to a method for determining the rotation speed and temperature limit value of an aero gas turbine shaft engine. BACKGROUND

[0002] In the design process of an aero gas turbine shaft engine, the rotation speed and temperature limit value of a gas generator and a gas turbine outlet need to be determined to ensure the working safety of the engine and the flight safety of an airplane.

[0003] The determination of the rotation speed and temperature limit value of the engine generally needs to consider the engine manufacturing dispersion, the power demand in the whole working envelope of the airplane, and the performance attenuation of the engine in use, so as to ensure that the engine can output the power meeting the demand of the airplane in the whole overhaul interval period under the condition of not exceeding the rotation speed and temperature limit value of the gas generator and the gas turbine outlet.

[0004] At present, when the rotation speed and temperature limit value of the engine is determined, the rotation speed and temperature of the gas generator and the gas turbine outlet in the design state are generally taken as the limit value, only the engine manufacturing dispersion is considered, and the influence of the power demand in the whole working envelope of the airplane and the performance attenuation of the engine in use is not fully considered.

[0005] With the increase of atmospheric temperature and flight height, the inlet air flow of the engine decreases, the amount of oxygen participating in combustion decreases, and the output power of the engine decreases, even if the rotation speed and temperature limit value of the engine is reached, since the rotation speed and temperature limit value of the engine does not fully consider the power demand in the whole working envelope of the airplane, the output power of the engine under the condition of high altitude and high temperature is still insufficient, and cannot meet the demand of the airplane.

[0006] After the engine is installed and works for a period of time, with the attenuation of the performance of the engine, the rotation speed and temperature of the engine reach the use limit value, but since the rotation speed and temperature limit value of the engine does not fully consider the influence of the performance attenuation in use, the output power is lower than the initial declared or designed power value, and cannot meet the demand of the airplane, thereby affecting the execution of the flight task and the flight safety, and the engine has to be returned to the factory for overhaul in advance, greatly increasing the use cost of the engine and seriously affecting the economy of the engine. SUMMARY

[0007] The present application provides a method for determining the rotation speed and temperature limit value of an aero gas turbine shaft engine, which fully considers the power demand in the whole working envelope of the airplane and the performance attenuation factor of the engine in use.

[0008] To achieve the above object, the technical scheme adopted by the present application is as follows.

[0009] A method for determining the speed and temperature limit values of an aero gas turbine shaft engine, comprising:

[0010] establishing an engine design state performance model to determine the design state gas generator speed and gas turbine outlet temperature ;

[0011] determining limit value A based on the aircraft power requirement based on the design state gas generator speed and gas turbine outlet temperature ;

[0012] determining limit value B based on the engine performance degradation based on limit value A;

[0013] performing strength check on the engine according to the determined limit value B;

[0014] conducting engine ground life test to simulate the performance degradation of the engine during the overhaul interval, and then conducting ground performance test on the engine to verify the applicability of the limit value on the ground;

[0015] conducting high-altitude performance test on the engine that has completed the ground life test to verify the applicability of the limit value at high altitude.

[0016] Optionally, the design state gas generator speed and gas turbine outlet temperature are determined according to the engine design state performance model.

[0017] Optionally, the limit value A includes gas generator speed limit value A1 and gas turbine outlet temperature limit value A2, when the power of the engine design state meets the condition that the demand power within the full operating envelope of the aircraft is greater than or equal to the demand power, the gas generator speed limit value A1 is equal to the design state gas generator speed , and the gas turbine outlet temperature limit value A2 is equal to the design state gas turbine outlet temperature ; when the condition is not met, the gas generator speed limit value A1 is , and the gas turbine outlet temperature limit value A2 is ,

[0018] wherein, and are calculated according to the following formula:

[0019] wherein, is the actual gas generator speed required to meet the demand power of the aircraft;

[0020] wherein, To meet the actual demand of the aircraft demand power, the gas turbine outlet temperature is determined.

[0021] Optionally, the limit value B includes a gas generator speed limit value B1 and a gas turbine outlet temperature limit value B2, the gas generator speed limit value B1 is , and the gas turbine outlet temperature limit value B2 is ,

[0022] wherein, and are calculated according to the following formula:

[0023] wherein, unit: rpm, is the engine overhaul interval, and the value range is 0-5000 hours;

[0024] wherein, unit: ℃, is the engine overhaul interval, and the value range is 0-5000 hours.

[0025] Optionally, the requirement of the strength check is not met, and the gas generator speed corresponding to the design state needs to be adjusted again and the gas turbine outlet temperature .

[0026] Optionally, the ground life test is carried out, if the engine gas generator speed is less than or equal to the gas generator speed limit value B1, and the gas turbine outlet temperature cannot reach the declared ground performance under the condition that it is less than or equal to the gas turbine outlet temperature limit value B2, then according to the test results, the and caused by performance degradation are adjusted, and the gas generator speed limit value B1 and the gas turbine outlet temperature limit value B2 are determined again.

[0027] Optionally, the high-altitude performance test is carried out, if the gas generator speed is less than or equal to the gas generator speed limit value B1, and the gas turbine outlet temperature cannot reach the declared high-altitude performance under the condition that it is less than or equal to the gas turbine outlet temperature limit value B2, then according to the test results, the and caused by performance degradation are adjusted, and the gas generator speed limit value B1 and the gas turbine outlet temperature limit value B2 are determined again.

[0028] The method of the present application can ensure that the engine can output power meeting the demand of the aircraft within the entire overhaul interval period without exceeding the limit values of the gas generator rotating speed and the gas turbine outlet temperature, while ensuring the safety of the engine operation, avoiding the interruption or limitation of the flight task due to insufficient power, improving the utilization rate of the engine, and prolonging the service life of the engine by fully considering the attenuation factors and reducing the frequency of component replacement and maintenance. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 A flowchart of a method for determining the rotating speed and temperature limit values of an aviation gas turbine shaft engine according to the present application;

[0030] Figure 2 A flowchart of an embodiment of the method for determining the rotating speed and temperature limit values of an aviation gas turbine shaft engine according to the present application. DETAILED DESCRIPTION

[0031] The specific embodiments of the present application will be described in detail below. The present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the spirit of the present application, so the present application is not limited by the disclosed specific embodiments.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terms used only for describing specific embodiments, not for limiting the present application.

[0033] A method for determining the rotating speed and temperature limit values of an aviation gas turbine shaft engine, comprising the following steps:

[0034] S101: establishing an engine design state performance model to determine the gas generator rotating speed and the gas turbine outlet temperature of the design state. .

[0035] During the production and manufacturing of the engine, due to the influence of factors such as slight differences in raw materials, precision fluctuations in processing technology, etc., the same model and same batch of engines have certain differences in performance, quality, size, etc., resulting in engine manufacturing dispersion. Considering the influence of engine manufacturing dispersion, an engine design state performance model is established, and the gas generator rotating speed and the gas turbine outlet temperature corresponding to the design state are determined according to the model. .

[0036] ​​S102: Gas generator speed based on design conditions and gas turbine outlet temperature Determine the limit value A based on the aircraft power requirements. Limit value A includes the gas generator speed limit value A1 and the gas turbine outlet temperature limit value A2.

[0037] Gas generator speed corresponding to design conditions and gas turbine outlet temperature To constrain this, the engine's design power is calculated and compared with the required power within the aircraft's full operating envelope. It is then determined whether the condition that the engine's design power is greater than or equal to the required power within the aircraft's full operating envelope is met. If so, the gas generator speed limit value A1 is equal to the design gas generator speed. The gas turbine outlet temperature limit value A2 is equal to the design state gas turbine outlet temperature. If this is not met, then at the gas generator speed and gas turbine outlet temperature Add on the basis and Until the aircraft's power requirements are met, the gas generator speed limit value A1 is... The gas turbine outlet temperature limit value A2 is .

[0038] in and Calculate using the following formula:

[0039] ,in, The required gas generator speed to meet the actual power demands of the aircraft;

[0040] ,in, The gas turbine outlet temperature required to meet the actual power demand of the aircraft.

[0041] S103: Based on limit value A, determine limit value B based on engine performance degradation. Limit value B includes gas generator speed limit value B1 and gas turbine outlet temperature limit value B2.

[0042] Based on the limit value A determined in step S102, calculate the engine's performance degradation caused by the following factors. and Then the speed limit value B1 of the gas generator is The gas turbine outlet temperature limit value B2 is .

[0043] in and According to the following formula:

[0044] wherein unit: rpm, is the engine overhaul interval, and is in the range of 0-5000 hours;

[0045] wherein unit: ℃, is the engine overhaul interval, and is in the range of 0-5000 hours.

[0046] S104: Perform strength check on the engine according to the determined limit value B.

[0047] According to the gas generator speed limit value B1 and the gas turbine outlet temperature limit value B2 determined in step S103, perform strength check calculation on the engine, and if the requirements are met, proceed to step S105; if the requirements are not met, return to step S101 to re-adjust the gas generator speed and the gas turbine outlet temperature corresponding to the design state.

[0048] S105: Perform engine ground life test to simulate the performance degradation of the engine during the overhaul interval, and then perform ground performance test on the engine to verify the applicability of the limit value on the ground.

[0049] Perform engine ground life test to simulate the ground performance degradation of the engine during the entire overhaul interval, and after completing the test, perform performance calibration on the engine. If the gas generator speed is less than or equal to the gas generator speed limit value B1, and the gas turbine outlet temperature is less than or equal to the gas turbine outlet temperature limit value B2, the declared ground performance can still be achieved, then proceed to step S106; if the declared ground performance cannot be achieved, return to step S103 to adjust and according to the test results, and re-determine the gas generator speed limit value B1 and the gas turbine outlet temperature limit value B2.

[0050] S106: Perform high-altitude performance test using the engine that has completed the ground life test to verify the applicability of the limit value at high altitude.

[0051] The engine which has completed the life test in step S105 is subjected to a high altitude performance test, and the high altitude performance of the engine is calibrated. If the gas generator rotation speed is less than or equal to the gas generator rotation speed limit value B1, and the gas turbine outlet temperature is less than or equal to the gas turbine outlet temperature limit value B2, and the declared high altitude performance can still be achieved, then the gas generator rotation speed limit value B1 and the gas turbine outlet temperature limit value B2 are finally confirmed. If the declared high altitude performance cannot be achieved, then the process returns to step S103, and the gas generator rotation speed limit value B1 and the gas turbine outlet temperature limit value B2 are re-determined according to the test results, taking into account the performance degradation caused by and .

Claims

1. A method of determining speed and temperature limit values for an aero-gas turbine shaft engine, characterized in that, Comprise: establishing an engine design state performance model to determine a design state gas generator speed and a gas turbine outlet temperature ; Based on the speed of the gas generator and the gas turbine outlet temperature A limit value A is determined based on the aircraft's power requirements. Limit value A includes a gas generator speed limit value A1 and a gas turbine outlet temperature limit value A2. When the engine's design power is greater than or equal to the required power within the aircraft's full operating envelope, the gas generator speed limit value A1 is equal to the gas generator speed. The gas turbine outlet temperature limit value A2 is equal to the gas turbine outlet temperature. ; If not satisfied, the gas generator rotation speed limit value A1 is , the gas turbine outlet temperature limit value A2 is , wherein, and calculated according to the following formula: wherein, the gas generator speed for meeting the actual need of the aircraft demand power; wherein, the gas turbine outlet temperature to meet the actual needs of the aircraft demand power; determining a limit value B based on engine performance degradation based on the limit value A; the limit value B includes a gas generator rotation speed limit value B1 and a gas turbine outlet temperature limit value B2, the gas generator rotation speed limit value B1 is , and the gas turbine outlet temperature limit value B2 is ​ wherein, and calculated according to the following formula: wherein in rpm, is the engine overhaul interval, which is in the range of 0-5000 hours; wherein in °C, is the engine overhaul interval, and has a value in the range of 0 to 5000 hours; According to the determined limit value B, the engine is subjected to strength checking; The ground life test of the engine is carried out to simulate the performance attenuation of the engine during the overhaul interval, and then the ground performance test of the engine is carried out to verify the applicability of the limit value on the ground; The high-altitude performance test of the engine which has completed the ground life test is carried out to verify the applicability of the limit value at high altitude.

2. The aero gas turbine shaft engine rotation speed and temperature limit value determination method according to claim 1, characterized in that, determining a design state gas generator speed from an engine design state performance model and a gas turbine outlet temperature .

3. The aero gas turbine shaft engine rotation speed and temperature limit value determination method according to claim 1, characterized in that, The requirement of the strength check is not met, and the design state corresponding to the gas generator speed needs to be adjusted again and the gas turbine outlet temperature .

4. The aero gas turbine shaft engine rotation speed and temperature limit value determination method according to claim 1, characterized in that, carrying out the ground life test, if the engine gas generator rotation speed is less than or equal to the gas generator rotation speed limit value B1 and the gas turbine outlet temperature is less than or equal to the gas turbine outlet temperature limit value B2, and the declared ground performance cannot be achieved, adjusting the performance degradation resulting from the test results and re-determining the gas generator rotation speed limit value B1 and the gas turbine outlet temperature limit value B2.

5. The aero gas turbine shaft engine rotation speed and temperature limit value determination method according to claim 1, characterized in that, carrying out the high-altitude performance test, if the gas generator rotation speed is less than or equal to the gas generator rotation speed limit value B1 and the gas turbine outlet temperature cannot reach the declared high-altitude performance under the condition that the gas turbine outlet temperature is less than or equal to the gas turbine outlet temperature limit value B2, adjusting the performance attenuation caused by and re-determining the gas generator rotation speed limit value B1 and the gas turbine outlet temperature limit value B2 according to the test results.

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