Helicopter turbine shaft engine installation loss test system and test method

Abstract

The invention belongs to a test flight test technology, and particularly relates to a helicopter turbine shaft engine installation loss test system and test method. The standards or regulations only require the installation loss of the engine, but a specific implementation mode of the measurement test of the installation loss of the engine is not given. In the installation loss test system, a data acquisition recorder acquires and records a drawing original machine signal, a GPS time signal, a pressure sensor signal and a temperature sensor signal and sends the signals to a processing unit, a pressure signal of an air inlet channel is acquired through a pressure sensor, and a temperature signal of the air inlet channel is acquired through a temperature sensor; the processing unit establishes a ground test bed experiment database according to test data obtained by ground test, establishes a flight test database according to test data obtained by flight test, extracts steady-state data of each flight state and corresponding torque TQ2 from the flight test database, and outputs the extracted steady-state data to the ground test bed experiment database. And finding the closest test data and the corresponding torque TQ1 in the ground test bed test database according to the steady-state data of the flight state, and calculating the installation loss TQ of the engine. The problem of helicopter turbine shaft engine installation loss measurement is solved.

Description

Technical Field

[0001] The invention belongs to flight test technology, and in particular relates to a helicopter turboshaft engine installation loss test system and a test method. Background Art

[0002] During the development of new helicopter models, especially during the verification of new engine installation, the engine installation loss measurement test is an indispensable test. Helicopters have corresponding standards or regulations for engine installation loss. The available power must be equal to the engine power (not exceeding the approved power) minus: (1) installation loss; (2) the power consumed by the accessories and service facilities for which certification and approval are applied. The above standards or regulations only put forward requirements for engine installation loss, but do not provide specific implementation methods for engine installation loss measurement tests. Summary of the invention

[0003] The present invention designs an engine installation loss test system and a test method for a helicopter turboshaft engine, which are used to obtain the installation loss of the turboshaft engine installed on a helicopter.

[0004] In one aspect, the present invention provides a helicopter turboshaft engine installation loss test system, which includes a data acquisition recorder, a GPS antenna, a pressure sensor, a temperature sensor and a processing unit, wherein the data acquisition recorder collects and records the extraction source machine signal, the GPS time signal, the pressure sensor signal and the temperature sensor signal and sends them to the processing unit, the pressure signal of the air inlet is collected by the pressure sensor, and the temperature signal of the air inlet is collected by the temperature sensor; the processing unit establishes a ground test bench experimental database according to the test data obtained by the ground test, establishes a flight test database according to the test data obtained by the flight test, extracts the steady-state data of each flight state and the corresponding torque TQ2 in the flight test database, finds the closest test data and the corresponding torque TQ1 in the ground test bench test database according to the steady-state data of the flight state, and calculates the engine installation loss △TQ by the following formula:

[0005] △TQ=(TQ2-TQ1) / TQ2×100%.

[0006] Advantageously, the raw engine signals include speed, engine intake duct pressure, engine intake duct temperature, ambient air temperature, engine gas turbine speed and engine torque.

[0007] Advantageously, the data acquisition recorder and the processing unit are mounted on a test equipment mounting frame on the floor inside the helicopter cabin or on a ground test bench.

[0008] Advantageously, the pressure sensor collects pressure signals by separating the pressure sensor from the measuring position, and transmits the pressure signal through a transparent rubber hose, and a pressure probe is arranged at the other end of the transparent rubber hose.

[0009] Advantageously, the temperature sensor is a Pt100 industrial platinum thermal resistor.

[0010] In another aspect, the present invention further provides a method for testing a helicopter turboshaft engine using the above-mentioned installation loss system, the method comprising the following steps:

[0011] S1. The engine is installed on a ground test bench, and a ground test bench test is performed to simulate the helicopter's hovering flight state, climbing flight state, level flight state and descending flight state, to obtain a ground test bench test database under each state;

[0012] S2. The engine is installed on the helicopter, and flight tests of the helicopter in hovering flight state, climbing flight state, level flight state and descending flight state are performed to obtain a flight test database in each state;

[0013] S3. Extracting steady-state data of each flight state from the flight test database and reading the corresponding engine torque TQ2;

[0014] S4, using the speed, outside air temperature, engine gas turbine speed, and intake duct temperature sensor temperature parameters in the steady-state data as a benchmark, find the closest ground test bench data column and the corresponding torque TQ1 in the ground test bench test database;

[0015] S5. Calculate the engine installation loss △TQ under each state:

[0016] △TQ=(TQ2-TQ1) / TQ2×100%.

[0017] Advantageously, during the ground test bench test simulating the hovering flight state of a helicopter, the engine gas turbine speed NG is adjusted to control the engine power to operate stably from 80% to 106% at intervals of 2%, and winds of different temperatures ranging from -40°C to +50°C at intervals of 2°C and a wind speed close to zero are blown into the engine air inlet, and the test data under each operating condition is recorded.

[0018] Advantageously, during the ground test bench test simulating the climbing flight state of a helicopter, the engine power is stably operated at 100% and 102% by adjusting the engine gas turbine speed NG, and winds of different temperatures ranging from -40°C to 50°C with intervals of 2°C and different wind speeds of 45kts-NG102% and 68kts-NG100% are blown into the engine air inlet, and the test data under each operating condition is recorded.

[0019] Advantageously, during the ground test bench test simulating the level flight state of a helicopter, the engine power is stably operated from 80% to 106% at intervals of 2% by adjusting the engine gas turbine speed NG, and winds of different temperatures ranging from -40°C to +50°C at intervals of 2°C and different wind speeds ranging from 40kts to 140kts at intervals of 10kts are blown into the engine air inlet, and the test data under each operating condition is recorded.

[0020] Advantageously, during the ground test bench test simulating the helicopter descent flight state, the engine power is adjusted to the power when the helicopter descent rate is simulated at 1000ft / min by adjusting the engine gas turbine speed NG for stable operation, and different temperatures of 68kts at intervals of 2°C from -40°C to +50°C are blown into the engine inlet, and the test data under each working condition is recorded.

[0021] Beneficial effects: By collecting key test data through the designed test system, the engine installation loss data is obtained by comparing and analyzing the flight test data with the ground test bench test data, which solves the problem of helicopter turboshaft engine installation loss measurement.

[0022] The features, functions, and advantages that have been discussed can be achieved independently in various examples or may be combined in yet other examples. Further details of the examples can be seen with reference to the following description and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Examples, as well as preferred modes of use, other objects and description thereof, will be best understood by reference to the following detailed description of examples of the invention when read in conjunction with the accompanying drawings, in which:

[0024] Figure 1 Schematic diagram of the test frame for the installation loss test system;

[0025] Figure 2 Schematic diagram of the installation loss test method. DETAILED DESCRIPTION

[0026] The disclosed examples will be more fully described with reference to the accompanying drawings, in which some (but not all) of the disclosed examples are shown. In fact, many different examples may be described and these examples should not be construed as limited to the examples set forth herein. Instead, these examples are described so that this disclosure will be thorough and complete and will fully convey the scope of the disclosure to those skilled in the art.

[0027] See also Figure 1 The helicopter turboshaft engine installation loss test system includes a data acquisition recorder, a GPS antenna, a pressure sensor, a temperature sensor, a processing unit and cables.

[0028] The data acquisition recorder is used to collect and record the original engine signals (speed, engine inlet pressure, engine inlet temperature, external atmospheric temperature, engine gas turbine speed, engine torque), GPS time signal, pressure sensor signal and temperature sensor signal. The data acquisition recorder is installed on the test equipment mounting frame on the floor inside the helicopter cabin (or the ground test bench) and fixed by bolt connection. In one embodiment, the data acquisition recorder uses the KAM-500 data acquisition recorder produced by ACRA Company of Ireland.

[0029] The GPS antenna is used to provide the GPS time signal to the data acquisition recorder as the time reference in the time history curve of each test parameter, and is connected to the data acquisition recorder using a cable. In order to enhance the strength of the search satellite signal, it is installed in principle at an unobstructed or weakly obstructed position of the helicopter (or test bench), usually installed on the upper part of the helicopter nose (or test bench). In one embodiment, the GPS antenna uses the L1 antenna produced by NovAtel, Canada.

[0030] The pressure sensor is used to collect the pressure signal of the air intake duct. Considering the installation environment of the measurement location and the applicable temperature range of the pressure sensor, the pressure sensor is separated from the measurement location for pressure signal collection. The pressure signal is transmitted using a transparent rubber hose. The pressure sensor is installed inside the cabin (or test bench) together with the data acquisition recorder. One end of the pressure sensor is connected to the data acquisition recorder using a cable, and the other end is connected to one end of the transparent rubber hose. The other end of the transparent rubber hose is provided with a pressure probe, which is fixed at the measurement location of the air intake duct.

[0031] The pressure probe is installed on the intake duct, and the distribution principle of the pressure probe on the intake duct is symmetrical and evenly arranged. The arrangement of the intake duct pressure measurement position is as follows: when observing the intake duct from the front of the intake duct, its cross section is circular, with the angle of 0 degrees directly above the front view and the clockwise angle as positive, and 6 measurement positions are selected at equal angles, namely 0 degrees, 60 degrees, 120 degrees, 180 degrees, 240 degrees, 300 degrees, etc.

[0032] The temperature sensor is used to collect the temperature signal of the intake duct. It is connected to the data acquisition recorder with a cable and installed inside the intake duct. To ensure the test accuracy, the temperature sensor uses a Pt100 industrial platinum thermal resistor. The temperature sensor is installed on the intake duct. The distribution principle is symmetrical and evenly arranged, and it is arranged at a different position from the intake duct pressure sensor. Therefore, the arrangement position of the temperature sensor is determined: when observing from the front end of the intake duct to the intake duct, its cross section is circular, with the angle of 0 degrees directly above the front view, and the clockwise angle is positive. Six measurement positions are selected at equal angles and are different from the arrangement position of the pressure sensor, namely 30 degrees, 90 degrees, 150 degrees, 210 degrees, 270 degrees, 330 degrees, etc. Use a cable to connect the temperature sensor to the data acquisition recorder.

[0033] See also Figure 2 , taking a certain type of helicopter turboshaft engine as an example, the testing method of the present invention is explained.

[0034] (1) The engine is installed on a ground test bench for testing and a ground test bench test database is obtained.

[0035] ① Install the engine on the ground test bench and complete the installation of the test equipment;

[0036] ②Power on the engine and test system, and start the engine;

[0037] ③ Ground test bench test simulating the hovering flight state of a helicopter: by adjusting the engine gas turbine speed (NG), the engine power is stably operated from 80% to 106% at intervals of 2%. During stable operation, different temperatures of -40°C to +50°C at intervals of 2°C and wind speed close to zero are blown into the engine inlet duct, and the GPS time, wind speed, engine inlet duct pressure, engine inlet duct temperature, outside atmospheric temperature (wind temperature), engine gas turbine speed, engine torque, inlet duct pressure sensor pressure (average value of each point), inlet duct temperature sensor temperature (average value of each point) under each working condition are recorded to establish a ground test bench test database simulating the hovering flight state of a helicopter (engine inlet duct pressure, engine inlet duct temperature, GPS time and other parameters are only for reference, wind speed, wind temperature, engine gas turbine speed, engine torque, inlet duct temperature sensor temperature are used for subsequent data comparison and analysis);

[0038] ④ Ground test bench test simulating the climbing flight state of a helicopter: by adjusting the engine gas turbine speed (NG), the engine power is stably operated at 100% and 102%. During stable operation, different temperatures of 45kts (NG is 102%) and 68kts (NG is 100%) at intervals of 2°C from -40°C to 50°C are blown into the engine inlet duct. The GPS time, speed (wind speed), engine inlet pressure, engine inlet temperature, outside atmospheric temperature (wind temperature), engine gas turbine speed, engine torque, inlet pressure sensor pressure (average value of each point), inlet temperature sensor temperature (average value of each point) under each working condition are recorded to establish a ground test bench test database simulating the climbing flight state of a helicopter (engine inlet pressure, engine inlet temperature, inlet pressure sensor pressure, GPS time and other parameters are only used for reference, wind speed, wind temperature, engine gas turbine speed, engine torque, inlet temperature sensor temperature are used for subsequent data comparison and analysis);

[0039] ⑤ Ground test bench test simulating helicopter level flight state: by adjusting the engine gas turbine speed (NG), the engine power is stably operated from 80% to 106% at intervals of 2%. During stable operation, different temperatures ranging from -40°C to +50°C at intervals of 2°C and wind speeds ranging from 40kts to 140kts at intervals of 10kts are blown into the engine inlet duct. The GPS time, speed (wind speed), engine inlet duct pressure, engine inlet duct temperature, outside atmospheric temperature (wind temperature), engine gas turbine speed, engine torque, inlet duct pressure sensor pressure (average value of each point), inlet duct temperature sensor temperature (average value of each point) under each working condition are recorded to establish a ground test bench test database simulating helicopter hovering flight state (engine inlet duct pressure, engine inlet duct temperature, inlet duct pressure sensor pressure, GPS time and other parameters are only used for reference, wind speed, wind temperature, engine gas turbine speed, engine torque, inlet duct temperature sensor temperature are used for subsequent data comparison and analysis);

[0040] ⑥ Ground test bench test simulating helicopter descent flight state: by adjusting the engine gas turbine speed (NG), the engine power is adjusted to the power when the helicopter descent rate is simulated to be 1000ft / min for stable operation. During stable operation, different temperatures ranging from -40℃ to +50℃ with an interval of 2℃ and 68kts wind are blown into the engine inlet duct, and the GPS time, speed (wind speed), engine inlet duct pressure, engine inlet duct temperature, external atmospheric temperature (wind temperature), engine gas turbine speed, engine torque, inlet duct pressure sensor pressure (average value of each point), inlet duct temperature sensor temperature (average value of each point) under each working condition are recorded to establish a ground test bench test database simulating helicopter hovering flight state (engine inlet duct pressure, engine inlet duct temperature, inlet duct pressure sensor pressure, GPS time and other parameters are only for reference, wind speed, wind temperature, engine gas turbine speed, engine torque, inlet duct temperature sensor temperature are used for subsequent data comparison and analysis);

[0041] ⑦ Turn off the engine and disconnect the power to the engine and test system.

[0042] (2) The engine is installed on a helicopter for flight testing to obtain a flight test database

[0043] ① Install the engine on the helicopter and complete the installation of the test equipment;

[0044] ②Power on the engine and test system, and start the engine;

[0045] ③ Conduct helicopter hovering flight test: The helicopter is subjected to ground effect hovering and ground effect hovering without ground effect at three weight states: maximum take-off weight, medium weight (average of maximum take-off weight and minimum test weight), and minimum test weight. The GPS time, speed, engine inlet pressure (average of each point), engine inlet temperature (average of each point), outside air temperature, engine gas turbine speed, and engine torque are recorded to establish a helicopter hovering flight test database (engine inlet pressure, engine inlet temperature, inlet pressure sensor pressure, GPS time and other parameters are only used for reference, speed, outside air temperature, engine gas turbine speed, engine torque, and inlet temperature sensor temperature are used for data comparison and analysis);

[0046] ④ Conduct helicopter climb flight test: The helicopter climbs at the maximum take-off weight with take-off power (NG is 102%), speed 45kts and maximum continuous power (NG is 100%), speed 68kts, respectively, and records GPS time, speed, engine inlet pressure (average value of each point), engine inlet temperature (average value of each point), outside air temperature, engine gas turbine speed, engine torque, and establish a helicopter climb flight test database (engine inlet pressure, engine inlet temperature, inlet pressure sensor pressure, GPS time and other parameters are only for reference, speed, outside air temperature, engine gas turbine speed, engine torque, inlet temperature sensor temperature are used for data comparison and analysis);

[0047] ⑤ Conduct helicopter level flight test: The helicopter, under the maximum take-off weight, performs level flight at altitudes of 5000ft, 10000ft, and 15000ft, at speeds of 40kts, 60kts, 80kts, and 100kts and level flight speeds at maximum continuous power; at an altitude of 5000ft, lock the NG of one engine at 90%, and repeat the level flight work at 2% increments from 90% until the maximum continuous power is reached. After the engine completes this part, the other engine does the same work; record GPS time, speed, engine inlet pressure (average value of each point), engine inlet temperature (average value of each point), external atmospheric temperature, engine gas turbine speed, and engine torque, and establish a helicopter level flight test database (engine inlet pressure, engine inlet temperature, inlet pressure sensor pressure, GPS time and other parameters are only for reference, speed, external atmospheric temperature, engine gas turbine speed, engine torque, and inlet temperature sensor temperature are used for data comparison and analysis);

[0048] ⑥ Conduct helicopter descent flight test: The helicopter weight is not limited. Start from an altitude of 12,000ft and descend at a speed of 68kts and a descent rate of 1,000ft / min. Record GPS time, speed, engine inlet pressure (average value of each point), engine inlet temperature (average value of each point), outside air temperature, engine gas turbine speed, engine torque, and establish a helicopter descent flight test database (engine inlet pressure, engine inlet temperature, inlet pressure sensor pressure, GPS time and other parameters are only for reference; speed, outside air temperature, engine gas turbine speed, engine torque, and inlet temperature sensor temperature are used for data comparison and analysis).

[0049] ⑦The helicopter lands and shuts down the engine.

[0050] (3) Calculation of engine installation loss

[0051] ① Extract the steady-state data of each flight state from the flight test database and directly read the engine torque TQ2;

[0052] ② Taking the outside air temperature (wind temperature), engine gas turbine speed, intake duct temperature sensor temperature and other parameters in the steady-state data as the benchmark, find the ground test bench data column that is closest to the test data (temperature error does not exceed 1°C, speed error does not exceed 1%) in the ground test bench test database, and determine the torque TQ1 in this state during the ground test bench test;

[0053] ③ Calculate the engine installation loss △TQ:

[0054] △TQ=(TQ2-TQ1) / TQ2×100%.

[0055] A positive installation loss means that the engine has a power gain after being installed on the helicopter, and a negative installation loss means that the engine has a power loss after being installed on the helicopter. Actual test results show that the engine installation loss varies with speed.

[0056] Descriptions of different advantageous arrangements have been presented for purposes of illustration and description, but the description is not intended to be exclusive or limited to examples of the disclosed form. Many modifications and variations will be apparent to those of ordinary skill in the art. Additionally, different advantageous examples may be described as having different advantages over other advantageous examples. The selected example or examples are selected and described in order to best illustrate the principles of the examples, practical applications, and to enable those of ordinary skill in the art to understand the disclosure as having various examples with various modifications suitable for the particular use contemplated.

Claims

1. A helicopter turboshaft engine installation loss test system, characterized in that: The system includes a data acquisition recorder, a GPS antenna, a pressure sensor, a temperature sensor and a processing unit, wherein the data acquisition recorder collects and records the extraction original machine signal, the GPS time signal, the pressure sensor signal and the temperature sensor signal and sends them to the processing unit, collects the pressure signal of the air inlet through the pressure sensor, and collects the temperature signal of the air inlet through the temperature sensor; the processing unit establishes a ground test bench experimental database according to the test data obtained from the ground test, establishes a flight test database according to the test data obtained from the flight test, extracts the steady-state data of each flight state and the corresponding torque TQ2 from the flight test database, finds the closest test data and the corresponding torque TQ1 in the ground test bench test database according to the steady-state data of the flight state, and calculates the engine installation loss △TQ by the following formula: △TQ=(TQ2-TQ1) / TQ2×100%.

2. The helicopter turboshaft engine installation loss test system according to claim 1, characterized in that: The raw engine signals include speed, engine intake duct pressure, engine intake duct temperature, ambient air temperature, engine gas turbine speed and engine torque.

3. The helicopter turboshaft engine installation loss test system according to claim 1, characterized in that: The data acquisition recorder and the processing unit are installed on the internal floor of the helicopter cabin or on a test equipment mounting frame of a ground test bench.

4. The helicopter turboshaft engine installation loss test system according to claim 1, characterized in that: The pressure sensor collects pressure signals by separating the pressure sensor from the measuring position, and transmits the pressure signals through a transparent rubber hose, and a pressure probe is arranged at the other end of the transparent rubber hose.

5. The helicopter turboshaft engine installation loss test system according to claim 1, characterized in that: The temperature sensor is a Pt100 industrial platinum thermal resistor.

6. A method for testing a helicopter turboshaft engine installation loss system according to any one of claims 1 to 5, characterized in that: The method comprises the following steps: S1. The engine is installed on a ground test bench, and a ground test bench test is performed to simulate the helicopter's hovering flight state, climbing flight state, level flight state and descending flight state, to obtain a ground test bench test database under each state; S2. The engine is installed on the helicopter, and flight tests of the helicopter in hovering flight state, climbing flight state, level flight state and descending flight state are performed to obtain a flight test database in each state; S3. Extracting steady-state data of each flight state from the flight test database and reading the corresponding engine torque TQ2; S4, using the speed, outside air temperature, engine gas turbine speed, and intake duct temperature sensor temperature parameters in the steady-state data as a benchmark, find the closest ground test bench data column and the corresponding torque TQ1 in the ground test bench test database; S5. Calculate the engine installation loss △TQ under each state: △TQ=(TQ2-TQ1) / TQ2×100%.

7. The testing method according to claim 6, characterized in that: During the ground test bench test simulating the hovering flight state of a helicopter, the engine gas turbine speed is adjusted to NG, and the engine power is controlled to operate stably at intervals of 2% from 80% to 106%. Winds of different temperatures ranging from -40°C to +50°C in intervals of 2°C and with a wind speed close to zero are blown into the engine air inlet, and the test data under each operating condition is recorded.

8. The testing method according to claim 6, characterized in that: During the ground test bench test simulating the climbing flight state of a helicopter, the engine power was stably operated at 100% and 102% by adjusting the engine gas turbine speed NG, and winds of different temperatures ranging from -40°C to 50°C with an interval of 2°C and different wind speeds of 45kts-NG102% and 68kts-NG100% were blown into the engine inlet, and the test data under each operating condition was recorded.

9. The testing method according to claim 6, characterized in that: During the ground test bench test simulating the level flight state of a helicopter, the engine power was stably operated from 80% to 106% at intervals of 2% by adjusting the engine gas turbine speed NG, and winds of different temperatures ranging from -40°C to +50°C at intervals of 2°C and wind speeds ranging from 40kts to 140kts at intervals of 10kts were blown into the engine inlet, and the test data under each operating condition was recorded.

10. The testing method according to claim 6, characterized in that: During the ground test bench test simulating the helicopter descent flight state, the engine power is adjusted to the power when the helicopter descent rate is 1000ft / min by adjusting the engine gas turbine speed NG for stable operation, and different temperatures of -40℃ to +50℃ with intervals of 2℃ and 68kts wind are blown into the engine inlet, and the test data under each working condition is recorded.

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