Turboprop engine complete machine overtorsion test method

Abstract

The invention discloses a turboprop engine complete machine over-torque test method, which comprises the steps of S1, determining target requirements of a turboprop engine over-torque test, including an engine lubricating oil temperature target, a turbine inlet gas steady-state temperature target, an engine torque target, an engine output shaft rotating speed target and a test time requirement; s2, performing a performance calibration test on the turboprop engine before the test to obtain performance calibration data of the turboprop engine; s3, according to the target requirements of the turboprop engine over-torsion test and the performance calibration data obtained by the performance calibration test, carrying out the over-torsion test on the turboprop engine; and S4, performing decomposition inspection on the turboprop engine subjected to the over-torsion test. According to the invention, multiple methods of thermal power margin and rotating speed reduction of the engine are combined to carry out the over-torque test, the problem that part of turboprop engine over-torque tests cannot be realized is solved, the adaptability is high, the implementation is convenient, manpower and financial resources are saved, the consumed time is short, the test can be successful at one time, and the test cost is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of engine testing, and in particular, to a method for super-torque testing of a whole turboprop engine. Background Art

[0002] The engine overtorque test is an important test subject that must be carried out in the initial pre-flight prescribed test and finalization test of the national military standard GJB242A-2018 (4.4.1.4.4.3). The engine overtorque test includes: the engine with a power turbine should work for 15 minutes at the maximum allowable steady-state torque limit value (mechanical) not less than 120% of the torque value to verify the requirements of 3.2.4.10 (the maximum allowable steady-state torque (mechanical) limit value should be at least 20% higher than the specified value, and the specific value should be given in the model specification). The test can be run in stages, each stage is at least 2.5 minutes, the power turbine speed is equal to the highest possible speed when the maximum torque occurs in the use of the engine, but not greater than the takeoff limit speed or the limit speed of the single-engine working power state with a duration of not more than 2 minutes; the turbine inlet gas temperature is equal to the maximum allowable steady-state temperature. For engines with internal reducers, the lubricating oil temperature of the internal reducer is equal to the highest temperature when the maximum torque occurs in the use of the engine.

[0003] At present, the main methods for implementing engine over-torque test are to increase the intake temperature, bleed air, adjust the guide vane angle (guide vane area), retract and extend the nozzle, etc. Generally, the above methods need to be used in combination to complete the engine over-torque test.

[0004] Although the super torque test requirements of some types of engines can be achieved and met by increasing the intake temperature, bleed air, adjusting the guide vane angle (guide vane area), retracting and expanding the nozzle, etc., some of them are complicated to implement, difficult to control, and time-consuming. Some engines may not even meet the super torque test requirements according to the above methods. For example, the guide vane angle adjustment can only be performed in the assembly stage for some engines, and the adjustment of the turbine guide vane area must be calculated based on the influence of the engine turbine guide vane flow function on the engine performance. If the adjustment is not in place, it needs to be reassembled, and multiple iterations of calculation and assembly are required, which is time-consuming and labor-intensive. In addition, the retractable nozzle needs to be redesigned and processed according to the calculation of the corresponding nozzle, which has a long cycle and may not guarantee success at one time. It may also require multiple iterations of calculation and processing, which wastes manpower and financial resources. Summary of the invention

[0005] This application provides a turboprop engine whole machine overtorque test method to solve the existing engine overtorque The experiment has technical problems such as being cumbersome to implement, difficult to control, time-consuming, costly and having limited adaptability.

[0006] This application is implemented through the following scheme:

[0007] A method for supertorque testing of a turboprop engine, comprising the steps of:

[0008] S1. Determine the target requirements for the turboprop engine overtorque test, including the engine lubricating oil temperature target, turbine inlet gas steady-state temperature target, engine torque target, engine output shaft speed target, and test time requirements;

[0009] S2. Performing a performance calibration test on the turboprop engine before the test to obtain performance calibration data of the turboprop engine;

[0010] S3. Performing an overtorque test on the turboprop engine according to the overtorque test target requirements of the turboprop engine and the performance calibration data obtained from the performance calibration test;

[0011] S4. Disassemble and inspect the turboprop engine that has completed the super-torque test.

[0012] Furthermore, in step S1, the engine lubricating oil temperature target is specifically: for an engine with an internal reducer, the lubricating oil temperature of the internal reducer is equal to the highest temperature when the maximum torque occurs during the use of the engine.

[0013] Furthermore, in step S1, the turbine inlet gas steady-state temperature target is specifically: the turbine inlet gas steady-state temperature is equal to the maximum allowable steady-state temperature.

[0014] Furthermore, in step S1, the engine torque target is specifically: if the maximum allowable steady-state torque limit of the turboprop engine is 106%, the over-torque is 120% of the limit, that is, the engine torque target is 127.2% torque.

[0015] Furthermore, in step S1, the engine output shaft speed target is specifically: the maximum output shaft speed n1 when the engine has a maximum steady-state torque, wherein the maximum steady-state torque is the torque when the engine torque reaches 106% of the maximum value.

[0016] Furthermore, in step S1, the test time requirement is specifically as follows: 15 minutes are required to reach the lubricating oil temperature, turbine inlet gas steady-state temperature, output shaft speed, and torque target. The test is run in stages, each stage lasting at least 2.5 minutes.

[0017] Further, in step S1, when determining the turbine inlet gas temperature target, the power turbine Outlet temperature Instead of monitoring the turbine inlet gas temperature.

[0018] Furthermore, in step S1, when determining the test time, the test is run in three stages, each stage lasting 5 minutes.

[0019] Furthermore, in step S1, according to the corresponding relationship between the engine output shaft speed and the power turbine speed, the engine output shaft speed is reduced during over-torque, that is, the power turbine speed is reduced.

[0020] Furthermore, step S3 specifically includes the steps of:

[0021] S31. Based on the engine performance calibration data, estimate the engine power and air intake volume that can achieve the super torque test target as a test reference;

[0022] S32, according to the relationship between the propeller electronic control simulator and the output shaft speed, modify the relevant parameters in the propeller electronic control simulator to obtain the output shaft speed required for super torque;

[0023] S33, calculating the power rod angle required for the over-torque test according to the relationship between the power rod angle and the power, and between the power and the torque;

[0024] S34, calculating or estimating the torque and speed according to the over-torque target torque, and setting the corresponding alarm values ​​and protection values ​​of the torque, speed and temperature before the over-torque test;

[0025] S35, start the engine to ground slow speed state, and operate for 2 to 3 minutes;

[0026] S36, push the engine up to the air slow state, and work for 3 to 5 minutes;

[0027] S37, push the engine state to 60% to 70% of the maximum rated power state, operate for 4 to 6 minutes, stabilize the lubricating oil temperature within the test requirement range, and heat the intake air heating device according to the required inlet temperature;

[0028] S38, continue to push the engine up to the middle state and work for 2 to 3 minutes;

[0029] S39. Slowly push up the engine power lever to reach the target torque value of the over-torque test. If the power turbine outlet temperature does not reach the target temperature, open the bleed air to the target temperature. When all indicators reach the over-torque target, start the 5-minute timer and pay close attention to the engine condition.

[0030] S310, pull the engine down to the intermediate state, turn off the bleed air, and wait for 2 to 3 minutes until the lubricating oil temperature stabilizes to the limit value;

[0031] S311, repeat steps S39 and S310 once;

[0032] S312, repeat step S39 once;

[0033] S313, slowly pull down the engine to the air slow state, turn off the bleed air and intake air heating, and work for 3 to 5 minutes;

[0034] S314, pull down the engine to the ground slow speed state and operate for 2 to 3 minutes;

[0035] S315: Stop the engine.

[0036] Compared with the prior art, this application has the following beneficial effects:

[0037] The present application provides a method for super-torque testing of a whole turboprop engine. The method for super-torque testing of a whole turboprop engine proposes for the first time to conduct super-torque testing by combining the thermal power margin of the engine with multiple methods such as reducing the rotational speed, thereby solving the problem that super-torque testing of some turboprop engines cannot be achieved and having strong adaptability. The present application provides an additional method for achieving super-torque testing, thus providing new ideas for other engines and greatly improving the technical level of super-torque testing of this type of engine. The present application is easy to implement, greatly saves manpower and financial resources, takes a short time and can succeed in one go, thus greatly shortening the time and cost of completing the test.

[0038] In addition to the above-described purposes, features and advantages, the present application also has other purposes, features and advantages. The present application will be further described in detail with reference to the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application.

[0040] Figure 1 It is a schematic flow chart of the method for super-torque testing of a turboprop engine as a whole according to the preferred embodiment of the present application. DETAILED DESCRIPTION

[0041] The embodiments of the present application are described in detail below in conjunction with the accompanying drawings, but the present application can be implemented in a variety of different ways defined and covered below.

[0042] like Figure 1 As shown, the preferred embodiment of the present application provides 1. A method for super torque testing of a turboprop engine, characterized in that it comprises the steps of:

[0043] S1. Determine the target requirements for the turboprop engine overtorque test, including the engine lubricating oil temperature target, turbine inlet gas steady-state temperature target, engine torque target, engine output shaft speed target, and test time requirements;

[0044] S2. Performing a performance calibration test on the turboprop engine before the test to obtain performance calibration data of the turboprop engine;

[0045] S3. Performing an overtorque test on the turboprop engine according to the overtorque test target requirements of the turboprop engine and the performance calibration data obtained from the performance calibration test;

[0046] S4. Disassemble and inspect the turboprop engine that has completed the super-torque test.

[0047] This embodiment provides a method for testing the supertorque of a turboprop engine as a whole. The over-torque test method proposes for the first time to conduct an over-torque test by combining the engine's thermal power margin with multiple methods such as reducing the speed, which solves the problem that over-torque tests on some turboprop engines cannot be achieved and has strong adaptability. The present embodiment provides an additional method for achieving over-torque tests, provides new ideas for other engines, and greatly improves the technical level of over-torque tests for this type of engine. The present embodiment is easy to implement, greatly saves manpower and financial resources, takes a short time and can succeed in one go, greatly shortening the time and cost to complete the test.

[0048] Preferably, in step S1, the engine lubricating oil temperature target is specifically: for an engine with an internal reducer, the lubricating oil temperature of the internal reducer is equal to the highest temperature when the maximum torque occurs during engine use.

[0049] Preferably, in step S1, the turbine inlet gas steady-state temperature target is specifically: the turbine inlet gas steady-state temperature is equal to the maximum allowable steady-state temperature. Since the turbine inlet gas temperature is high and difficult to test, the complex structure makes modification difficult, and modification may cause a series of problems such as leakage and uneven temperature field, the power turbine outlet temperature is used instead of the turbine inlet gas temperature for monitoring according to the corresponding relationship between the turbine inlet gas temperature and the power turbine outlet temperature.

[0050] Preferably, in step S1, the engine torque target is specifically: if the maximum allowable steady-state torque limit of the turboprop engine is 106%, the over-torque is 120% of the limit, that is, the engine torque target is 127.2% torque.

[0051] Preferably, in step S1, the engine output shaft speed target is specifically: the maximum output shaft speed n1 when the engine has the maximum steady-state torque, wherein the maximum steady-state torque is the torque when the engine torque reaches 106% of the maximum value. The national military standard requires that the power turbine speed during the over-torque test is equal to the maximum possible speed when the maximum over-torque occurs during engine use. If the propeller pitch adjustment mechanism is abnormal, the propeller output shaft speed may drop to n1, at which time the engine torque reaches the maximum value of 106% torque. Therefore, the maximum output shaft speed when the maximum steady-state torque (106%) occurs is n1. There is a corresponding relationship between the engine output shaft speed and the power turbine speed. Reducing the engine output shaft speed during over-torque means reducing the power turbine speed.

[0052] Preferably, in step S1, the test time requirement is specifically: 15 minutes to reach the target oil temperature, turbine inlet gas steady-state temperature, output shaft speed, and torque, and the test is run in stages, each stage is at least 2.5 minutes. The system runs in stages, with each stage lasting 5 minutes.

[0053] The over torque of a certain type of turboprop engine is 127.2%. According to the torque formula (where P is power and n is output shaft speed.) During over-torque, the engine output shaft speed n is reduced by 6%, which can increase the torque value. In addition, a certain turboprop engine has a thermal power margin. Moving the power lever above the rated power position will cause the required power to reach 100% to 120% of the maximum rated power. In this way, when the power reaches 120% of the maximum rated power, an over-torque torque of 127.2% can be achieved.

[0054] In summary, a certain type of turboprop engine in the above embodiment achieves super torque mainly by reducing the output shaft speed and utilizing the thermal power margin, thereby solving the problem that super torque tests of some types of turboprop engines cannot be performed.

[0055] In a preferred embodiment of the present application, step S3 specifically includes the steps of:

[0056] S31. Based on the engine performance calibration data, estimate the engine power and air intake volume that can achieve the super torque test target as a test reference;

[0057] S32, according to the relationship between the propeller electronic control simulator and the output shaft speed, modify the relevant parameters in the propeller electronic control simulator to obtain the output shaft speed required for super torque;

[0058] S33, calculating the power rod angle required for the over-torque test according to the relationship between the power rod angle and the power, and between the power and the torque;

[0059] S34, calculating or estimating the torque and speed according to the over-torque target torque, and setting the corresponding alarm values ​​and protection values ​​of the torque, speed and temperature before the over-torque test;

[0060] S35, start the engine to ground slow speed state, and operate for 2 to 3 minutes;

[0061] S36, push the engine up to the air slow state, and work for 3 to 5 minutes;

[0062] S37, push the engine state to 60% to 70% of the maximum rated power state, operate for 4 to 6 minutes, stabilize the lubricating oil temperature within the test requirement range, and heat the intake air heating device according to the required inlet temperature to ensure better operation of the engine rotor;

[0063] S38, continue to push the engine up to the intermediate state, work for 2 to 3 minutes, the intermediate state is a transition state;

[0064] S39. Slowly push up the engine power lever to reach the target value of the over-torque test torque. At this time, the engine output shaft n is reduced by 6%, so that the maximum rated power is within the range of 120% and the torque reaches 127.2% torque (over-torque requirement); if the power turbine outlet temperature does not reach the temperature target value, open the bleed air to the target temperature, and all indicators reach the over-torque target. Start timing for 5 minutes and pay close attention to the engine condition;

[0065] S310, pull the engine down to the intermediate state, turn off the bleed air, and wait for 2 to 3 minutes until the lubricating oil temperature stabilizes to the limit value;

[0066] S311, repeat steps S39 and S310 once;

[0067] S312, repeat step S39 once;

[0068] S313, slowly pull down the engine to the air slow state, turn off the bleed air and intake air heating, and work for 3 to 5 minutes;

[0069] S314, pull down the engine to the ground slow speed state and operate for 2 to 3 minutes;

[0070] S315: Stop the engine.

[0071] In summary, the above-mentioned embodiments of the present application propose for the first time to conduct an over-torque test by combining the thermal power margin of the engine with multiple methods such as reducing the output shaft speed, which solves the problem that the over-torque test of a certain turboprop engine cannot be realized. It is relatively easy to implement, greatly saves manpower and financial resources, and succeeds at one time, greatly shortening the time to complete the test.

[0072] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0073] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A method for supertorque test of a turboprop engine, characterized in that: Includes steps: S1. Determine the target requirements for the turboprop engine overtorque test, including the engine lubricating oil temperature target, turbine inlet gas steady-state temperature target, engine torque target, engine output shaft speed target, and test time requirements; S2. Performing a performance calibration test on the turboprop engine before the test to obtain performance calibration data of the turboprop engine; S3. Performing an overtorque test on the turboprop engine according to the overtorque test target requirements of the turboprop engine and the performance calibration data obtained from the performance calibration test; S4. Disassemble and inspect the turboprop engine that has completed the super-torque test.

2. The turboprop engine whole machine overtorque test method according to claim 1, characterized in that: In step S1, the engine lubricating oil temperature target is specifically: for an engine with an internal speed reducer, the lubricating oil temperature of the internal speed reducer is equal to the highest temperature when the maximum torque occurs during the use of the engine.

3. The turboprop engine whole machine overtorque test method according to claim 2, characterized in that: In step S1, the turbine inlet gas steady-state temperature target is specifically: the turbine inlet gas steady-state temperature is equal to the maximum allowable steady-state temperature.

4. The turboprop engine whole machine super torque test method according to claim 3, characterized in that: In step S1, the engine torque target is specifically: if the maximum allowable steady-state torque limit of the turboprop engine is 106%, the over-torque is 120% of the limit, that is, the engine torque target is 127.2% torque.

5. The turboprop engine whole machine super torque test method according to claim 4, characterized in that: In step S1, the engine output shaft speed target is specifically: the maximum output shaft speed n1 when the engine has a maximum steady-state torque, wherein the maximum steady-state torque is the torque when the engine torque reaches 106% of the maximum value.

6. The turboprop engine whole machine overtorque test method according to claim 5, characterized in that: In step S1, the test time requirement is specifically: 15 minutes to reach the lubricating oil temperature, turbine inlet gas steady-state temperature, output shaft speed, and torque target. The test is run in stages, each stage is at least 2.5 minutes.

7. The turboprop engine whole machine overtorque test method according to claim 3, characterized in that: In step S1, when determining the turbine inlet gas temperature target, the power turbine outlet temperature is used to monitor instead of the turbine inlet gas temperature.

8. The turboprop engine whole machine overtorque test method according to claim 6, characterized in that: In step S1, when determining the test time, the test is divided into three stages, each stage lasting 5 minutes.

9. The turboprop engine whole machine overtorque test method according to claim 5, characterized in that: In step S1, according to the corresponding relationship between the engine output shaft speed and the power turbine speed, the engine output shaft speed is reduced during over-torque, that is, the power turbine speed is reduced.

10. The turboprop engine whole machine super torque test method according to claim 1, characterized in that: Step S3 specifically includes the following steps: S31. Based on the engine performance calibration data, estimate the engine power and air intake volume that can achieve the super torque test target as a test reference; S32, according to the relationship between the propeller electronic control simulator and the output shaft speed, modify the relevant parameters in the propeller electronic control simulator to obtain the output shaft speed required for super torque; S33, calculating the power rod angle required for the over-torque test according to the relationship between the power rod angle and the power, and between the power and the torque; S34, calculating or estimating the torque and speed according to the over-torque target torque, and setting the corresponding alarm values ​​and protection values ​​of the torque, speed and temperature before the over-torque test; S35, start the engine to ground slow speed state, and operate for 2 to 3 minutes; S36, push the engine up to the air slow state, and work for 3 to 5 minutes; S37, push the engine state to 60% to 70% of the maximum rated power state, operate for 4 to 6 minutes, stabilize the lubricating oil temperature within the test requirement range, and heat the intake air heating device according to the required inlet temperature; S38, continue to push the engine up to the middle state and work for 2 to 3 minutes; S39. Slowly push up the engine power lever to reach the target torque value of the over-torque test. If the power turbine outlet temperature does not reach the target temperature, open the bleed air to the target temperature. When all indicators reach the over-torque target, start the 5-minute timer and pay close attention to the engine condition. S310, pull the engine down to the intermediate state, turn off the bleed air, and wait for 2 to 3 minutes until the lubricating oil temperature stabilizes to the limit value; S311, repeat steps S39 and S310 once; S312, repeat step S39 once; S313, slowly pull down the engine to the air slow state, turn off the bleed air and intake air heating, and work for 3 to 5 minutes; S314, pull down the engine to the ground slow speed state and operate for 2 to 3 minutes; S315: Stop the engine.

Images