Turboprop engine complete machine overtemperature test method

Abstract

The invention discloses a turboprop engine complete machine overtemperature test method comprising the following steps: S1, determining turboprop engine overtemperature test target requirements including a temperature target, a 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, performing an overtemperature test on the turboprop engine according to the target requirement of the overtemperature test of the turboprop engine and the performance calibration data obtained by the performance calibration test; and S4, performing decomposition inspection on the turboprop engine subjected to the over-temperature test. The overtemperature test is carried out by utilizing the thermal power margin of the engine, the problem that the overtemperature test is difficult to realize by combining multiple methods of some engines is solved, the implementation is convenient, the manpower and financial resources are saved, the consumed time is short, the test can be successful at one time, and the time and the cost for completing the test are greatly shortened.

Description

Technical Field

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

[0002] The engine overtemperature test is an important test subject that must be conducted in the initial pre-flight prescribed test and finalization test. Its purpose is to evaluate the structural integrity of the hot end component rotor under high temperature conditions. The engine overtemperature test should be carried out for at least 5 minutes at a temperature that is at least 45°C higher than the maximum allowable steady-state gas temperature at the inlet of the first-stage turbine rotor and at a speed not lower than the maximum allowable steady-state speed. After the test, the dimensions of the parts and components are within the allowable limits and there is no sign of imminent failure, which means that the test is considered to be completed satisfactorily.

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

[0004] The over-temperature 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 releasing the nozzle, anti-icing and other methods, but some of them are complicated to implement, difficult to control, and time-consuming. Even some engines cannot meet the over-temperature test requirements according to the above methods. For example, the guide vane angle can only be adjusted in the assembly stage of some engines, and the adjustment of the turbine guide vane area must be calculated based on the influence of the engine turbine guide vane stream 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 takes a long time and may not guarantee success at one time. It requires multiple iterations of calculation and processing, which wastes manpower and financial resources. Summary of the invention

[0005] The present application provides a method for over-temperature testing of a whole turboprop engine to solve the technical problems of existing engine over-temperature testing, such as being complicated 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 over-temperature testing of a turboprop engine comprises the following steps:

[0008] S1. Determine the target requirements for turboprop engine overtemperature testing, including temperature target, 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. Perform an over-temperature test on the turboprop engine according to the turboprop engine over-temperature test target requirements and the performance calibration data obtained from the performance calibration test;

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

[0012] Furthermore, in step S1, the temperature target is specifically a target requirement of the temperature before the first-stage turbine Tt4.1.

[0013] Furthermore, the target requirement for the first-stage turbine inlet temperature Tt4.1 is specifically: the Tt4.1 temperature is at least 45°C higher than the first-stage turbine rotor inlet steady-state maximum allowable gas temperature.

[0014] Furthermore, in step S1, the speed target is a speed target requirement of the first-stage turbine rotor.

[0015] Furthermore, the speed target requirement of the first-stage turbine rotor is specifically: the first-stage turbine rotor is not lower than the maximum allowable steady-state speed, that is, the high-pressure rotor speed is not lower than 100%.

[0016] Furthermore, in step S1, the test time requirement is specifically: when the temperature and the high-pressure rotor speed both reach the requirements, run for 5 minutes.

[0017] Furthermore, in step S1, in the over-temperature test, the power turbine outlet temperature is tested instead of monitoring the first-stage turbine inlet temperature Tt4.1.

[0018] Furthermore, step S3 specifically includes the steps of:

[0019] S31. Based on the engine performance calibration data, estimate the engine power and bleed air volume that meet the over-temperature test target as a test reference;

[0020] S32. Calculate the power rod angle required for the over-temperature test based on the relationship between power and power turbine outlet temperature, and between the power rod angle and power, as a test reference;

[0021] S33, calculate and estimate the torque and speed according to the target temperature of the over-temperature test, and set the corresponding alarm value and protection value of the torque, speed and temperature before the over-temperature test;

[0022] S34, start the engine to ground slow speed state, and operate for 2 to 3 minutes;

[0023] S35, push the engine up to the air slow state, and work for 3 to 5 minutes;

[0024] S36. Push the engine to 60% to 70% of the maximum rated power and operate for 4 to 6 minutes to stabilize the lubricating oil temperature within the test requirement range. The intake air heating device heats the air according to the required inlet temperature, and the bleed air system bleeds air according to the required bleed air flow rate.

[0025] S37. After the engine is stable at the maximum rated power for 2 to 3 minutes, push up the power lever according to the over-temperature test target temperature and high-pressure speed of 100%, so that the current power of the engine is greater than the maximum rated power and less than or equal to the maximum power of the engine thermal power margin. If the temperature and speed reach the test target, start timing for 5 minutes and pay close attention to the engine condition;

[0026] S38. After the overheating is completed for 5 minutes, the engine is slowly pulled down to the intermediate rated power state, the bleed air and intake air heating devices are turned off, and the engine is operated for 2 to 3 minutes;

[0027] S39, pull down the engine to the air slow state, and work for 2 to 3 minutes;

[0028] S310, pull down the engine to the ground slow speed state and operate for 2 to 3 minutes;

[0029] S311: The engine is stopped.

[0030] Furthermore, in step S37, when the current engine power is greater than the maximum rated power and less than or equal to the maximum power of the engine thermal power margin, if the temperature and the speed have not reached the test target, the bleed air flow is adjusted to make the engine reach the test target.

[0031] Compared with the prior art, this application has the following beneficial effects:

[0032] The present application provides a method for over-temperature testing of a whole turboprop engine. The method for over-temperature testing of a whole turboprop engine proposes for the first time to use the thermal power margin of the engine to conduct an over-temperature test, which solves the problem that over-temperature testing of certain engines is difficult to achieve even with a combination of multiple methods, and has strong adaptability. The present application provides an additional method for achieving over-temperature testing, which provides new ideas for other engines and greatly improves the technical level of over-temperature 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, which greatly shortens the time and cost of completing the test.

[0033] 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

[0034] 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.

[0035] Figure 1 It is a schematic flow chart of the turboprop engine whole machine overtemperature test method according to the preferred embodiment of the present application. DETAILED DESCRIPTION

[0036] 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.

[0037] like Figure 1 As shown, the preferred embodiment of the present application provides a method for over-temperature testing of a turboprop engine, comprising the steps of:

[0038] S1. Determine the target requirements for turboprop engine overtemperature testing, including temperature target, speed target and test time requirements;

[0039] S2. Performing a performance calibration test on the turboprop engine before the test to obtain performance calibration data of the turboprop engine;

[0040] S3. Perform an over-temperature test on the turboprop engine according to the turboprop engine over-temperature test target requirements and the performance calibration data obtained from the performance calibration test;

[0041] S4. Disassemble and inspect the turboprop engine that has completed the over-temperature test.

[0042] The present embodiment provides a method for over-temperature testing of a turboprop engine as a whole. The method for over-temperature testing of a turboprop engine as a whole proposes for the first time to use the thermal power margin of the engine to conduct an over-temperature test, which solves the problem that it is difficult to implement an over-temperature test for some engines by combining multiple methods, and has strong adaptability. The present embodiment provides an additional method for implementing an over-temperature test, which provides a new idea for other engines and greatly improves the technical level of over-temperature testing of 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, which greatly shortens the time and cost of completing the test.

[0043] Preferably, in step S1, the temperature target is specifically a target requirement of the first stage turbine inlet temperature Tt4.1. The target requirement of the first stage turbine inlet temperature Tt4.1 is specifically: Tt4.1 temperature is at least 45°C higher than the first stage turbine rotor inlet steady-state maximum allowable gas temperature.

[0044] Specifically, in step S1, in the over-temperature test, the power turbine outlet temperature is tested instead of monitoring the first-stage turbine inlet temperature Tt4.1.

[0045] For a certain turboprop engine, it is difficult to directly measure the temperature Tt4.1 before the first-stage turbine. The above embodiment takes into account a series of problems such as the high temperature level of the first-stage high-pressure turbine front rotor, the harsh test environment, the complex structure and the difficult modification of the test layout, which will cause air leakage, cooling structure changes, greatly reduced strength and reliability, and uneven temperature, pressure and flow fields. In the over-temperature test, the power turbine outlet temperature is tested to indirectly monitor the Tt4.1 temperature. According to the relationship between the Tt4.1 temperature and the power turbine outlet temperature, the power turbine outlet temperature required for the over-temperature test is calculated, which solves a series of problems such as the high temperature level of the first-stage high-pressure turbine front rotor, the harsh test environment, the complex structure and the difficult modification of the test layout, which will cause air leakage, cooling structure changes, greatly reduced strength and reliability, and uneven temperature, pressure and flow fields.

[0046] Preferably, in step S1, the speed target is the speed target requirement of the first-stage turbine rotor, and the speed target requirement of the first-stage turbine rotor is specifically: the first-stage turbine rotor is not lower than the maximum allowable steady-state speed, that is, the high-pressure rotor speed is not lower than 100%.

[0047] Preferably, in step S1, the test time requirement is specifically: when the temperature and the high-pressure rotor speed both meet the requirements, run for 5 minutes.

[0048] In a preferred embodiment of the present application, step S3 specifically includes the steps of:

[0049] S31. Based on the engine performance calibration data, estimate the engine power and bleed air volume that meet the over-temperature test target as a test reference;

[0050] S32. Calculate the power rod angle required for the over-temperature test based on the relationship between power and power turbine outlet temperature, and between the power rod angle and power, as a test reference;

[0051] S33, calculate and estimate the torque and speed according to the target temperature of the over-temperature test, and set the corresponding alarm value and protection value of the torque, speed and temperature before the over-temperature test;

[0052] S34, start the engine to ground slow speed state, and operate for 2 to 3 minutes;

[0053] S35, push the engine up to the air slow state, and work for 3 to 5 minutes;

[0054] S36. Push the engine to 60% to 70% of the maximum rated power and operate for 4 to 6 minutes to stabilize the lubricating oil temperature within the test requirement range. The intake air heating device heats the air according to the required inlet temperature, and the bleed air system bleeds air according to the required bleed air flow rate.

[0055] S37. After the engine is pushed up and stabilized at the maximum rated power state for 2 to 3 minutes, push up the power lever according to the over-temperature test target temperature and high-pressure speed of 100%, so that the current power of the engine is greater than the maximum rated power and less than or equal to the maximum power of the engine thermal power margin. For example, when the maximum power of the thermal power margin is reached, that is, 120% of the maximum rated power, if the temperature and speed reach the test target, start timing for 5 minutes and pay close attention to the engine condition;

[0056] S38. After the overheating is completed for 5 minutes, the engine is slowly pulled down to the intermediate rated power state (the engine is reduced from the overheating state to the intermediate rated power state, which can gradually reduce the state of the engine and the internal temperature without causing problems caused by sudden temperature changes), and the bleed air and intake air heating devices are turned off and work for 2 to 3 minutes;

[0057] S39, pull down the engine to the air slow state, and work for 2 to 3 minutes;

[0058] S310, pull down the engine to the ground slow speed state and operate for 2 to 3 minutes;

[0059] S311: The engine is stopped.

[0060] Preferably, in step S37, when the current power of the engine is greater than the maximum rated power and less than or equal to the maximum power of the engine thermal power margin, for example, if the maximum power of the thermal power margin is reached, that is, 120% of the maximum rated power, if the temperature and speed have not reached the test target, the bleed air flow rate is adjusted to make the engine reach the test target, that is, when the temperature and speed reach the test target, the timing is started for 5 minutes, and the engine condition is closely monitored.

[0061] The above embodiment completes the over-temperature test according to the thermal power margin function unique to a turboprop engine. The thermal power margin of the engine is to move the power lever above the rated power position, which will cause the required power to reach 100% to 120% of the maximum rated power. A turboprop engine can successfully complete the over-temperature test once by adding the thermal power margin function of a turboprop engine.

[0062] In summary, the above embodiments of the present application propose for the first time to mainly utilize the thermal power margin of the engine to conduct over-temperature testing, which solves the problem that it is difficult to achieve over-temperature testing for certain engines by combining multiple methods. 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.

[0063] 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.

[0064] 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 turboprop engine whole machine overtemperature test method, characterized in that: Includes steps: S1. Determine the target requirements for turboprop engine overtemperature testing, including temperature target, 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. Perform an over-temperature test on the turboprop engine according to the turboprop engine over-temperature test target requirements and the performance calibration data obtained from the performance calibration test; S4. Disassemble and inspect the turboprop engine that has completed the over-temperature test.

2. The turboprop engine whole machine overtemperature test method according to claim 1, characterized in that: In step S1, the temperature target is specifically the target requirement of the temperature before the first-stage turbine Tt4.

1.

3. The turboprop engine whole machine overtemperature test method according to claim 2, characterized in that: The target requirement for the first-stage turbine inlet temperature Tt4.1 is specifically: the Tt4.1 temperature is at least 45°C higher than the first-stage turbine rotor inlet steady-state maximum allowable gas temperature.

4. The turboprop engine whole machine overtemperature test method according to claim 1, characterized in that: In step S1, the speed target is the speed target requirement of the first-stage turbine rotor.

5. The turboprop engine whole machine overtemperature test method according to claim 4, characterized in that: The speed target requirement of the first-stage turbine rotor is specifically: the first-stage turbine rotor is not lower than the maximum allowable steady-state speed, that is, the high-pressure rotor speed is not lower than 100%.

6. The turboprop engine whole machine overtemperature test method according to claim 1, characterized in that: In step S1, the test time requirement is specifically: when the temperature and the high-pressure rotor speed both reach the requirements, run for 5 minutes.

7. The turboprop engine whole machine overtemperature test method according to claim 2, characterized in that: In step S1, in the over-temperature test, the power turbine outlet temperature is tested instead of monitoring the first-stage turbine inlet temperature Tt4.

1.

8. The turboprop engine whole machine overtemperature 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 bleed air volume that meet the over-temperature test target as a test reference; S32. Calculate the power rod angle required for the over-temperature test based on the relationship between power and power turbine outlet temperature, and between the power rod angle and power, as a test reference; S33, calculate and estimate the torque and speed according to the target temperature of the over-temperature test, and set the corresponding alarm value and protection value of the torque, speed and temperature before the over-temperature test; S34, start the engine to ground slow speed state, and operate for 2 to 3 minutes; S35, push the engine up to the air slow state, and work for 3 to 5 minutes; S36. Push the engine to 60% to 70% of the maximum rated power and operate for 4 to 6 minutes to stabilize the lubricating oil temperature within the test requirement range. The intake air heating device heats the air according to the required inlet temperature, and the bleed air system bleeds air according to the required bleed air flow rate. S37. After the engine is stable at the maximum rated power for 2 to 3 minutes, push up the power lever according to the over-temperature test target temperature and high-pressure speed of 100%, so that the current power of the engine is greater than the maximum rated power and less than or equal to the maximum power of the engine thermal power margin. If the temperature and speed reach the test target, start timing for 5 minutes and pay close attention to the engine condition; S38. After the overheating is completed for 5 minutes, the engine is slowly pulled down to the intermediate rated power state, the bleed air and intake air heating devices are turned off, and the engine is operated for 2 to 3 minutes; S39, pull down the engine to the air slow state, and work for 2 to 3 minutes; S310, pull down the engine to the ground slow speed state and operate for 2 to 3 minutes; S311: The engine is stopped.

9. The turboprop engine whole machine overtemperature test method according to claim 8, characterized in that: In step S37, when the current engine power is greater than the maximum rated power and less than or equal to the maximum power of the engine thermal power margin, if the temperature and the speed have not reached the test target, the bleed air flow is adjusted to make the engine reach the test target.

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