An overall engine test method for testing the high-altitude performance of an afterburner

Abstract

The present invention provides a whole-engine test method for testing the high-altitude performance of an afterburner. During engine bench tests, by adjusting the control schedule of the relationship between the throttle lever and the whole-engine speed, the fan speed when the whole engine engages the afterburner is reduced, and the afterburning performance test is carried out by controlling the throttle lever at this fan speed. The present invention conducts the afterburner performance test after reducing the speed on the ground bench, provides a basis for demonstrating the high-altitude performance in the improvement and modification design of the afterburner, takes into account the actual conditions at the afterburner inlet in the test compared with the sector test, and significantly reduces the test cost compared with the full-ring and high-altitude test bench tests.

Description

Technical Field

[0001] The present invention relates to a whole - machine test method for testing the high - altitude performance of an afterburner. Background Technique

[0002] In order to find out the performance of the afterburner component at high - altitude state points, the afterburner sector, afterburner full - ring test, and whole - machine high - altitude test bench test are usually adopted. Since the inlet of the sector test cannot fully simulate the actual inlet flow field state of the engine, and is affected by the wall - surface effect on both sides of the sector, the combustion performance and flow - field characteristics of the afterburner cannot be accurately evaluated. Although the afterburner full - ring test can simulate similar inlet flow field conditions in the test inlet transition section, it has high requirements for the gas source capacity and test equipment, and the test cost is high. The whole - machine high - altitude test bench test achieves the simulation and verification of the real working conditions, but the test cost is extremely high and is generally carried out during technical appraisal or type - approval tests.

[0003] As a result, during the improvement of the afterburner scheme and the modification design, due to financial constraints, the performance of the afterburner at high - altitude state points cannot be fully investigated. At present, the whole - machine test bench test only verifies the performance of the afterburner at the design point, and does not master the performance of the afterburner at high altitude (with reduced air flow, low pressure, and low - temperature inlet), and the performance evaluation of the afterburner is not comprehensive. Summary of the Invention

[0004] To solve the above - mentioned technical problems, the present invention provides a whole - machine test method for testing the high - altitude performance of an afterburner. This whole - machine test method for testing the high - altitude performance of an afterburner can simulate the high - altitude inlet conditions of the afterburner type when the engine is in the test - bench state, and achieve the purpose of investigating the high - altitude performance by comparing the performance after the reduction of rotation speed during the improvement of the afterburner scheme and the modification design.

[0005] The present invention is achieved through the following technical solutions.

[0006] A whole - machine test method for testing the high - altitude performance of an afterburner provided by the present invention, during the engine test - bench test, by adjusting the control plan of the relationship between the throttle lever and the whole - machine rotation speed, reducing the fan rotation speed when the whole - machine turns on the afterburner, and conducting the afterburning combustion performance test through the throttle lever control at this fan rotation speed.

[0007] The reduction of the fan rotation speed when the whole - machine turns on the afterburner makes the fan rotation speed of the whole - machine at the time of afterburner turning - on within a predetermined range to simulate the high - altitude inlet conditions.

[0008] It includes the following steps:

[0009] ① Obtain parameters: Obtain the aerodynamic parameters at the inlet of the afterburner inner flow path, the aerodynamic parameters at the inlet of the afterburner outer flow path, and the engine throttle state performance parameters recorded at the ground test stand point under a certain state point at high altitude in the simulation test.

[0010] ② Calculate the rotational speed: Calculate the ground test stand fan rotational speed that is close to the parameters of the high altitude state point to be simulated.

[0011] ③ Select the available rotational speed: Conduct a simulation, and select the fan rotational speed that meets the preset conditions.

[0012] ④ Input control: Input the fan rotational speed that meets the preset conditions into the controller through the control plan table.

[0013] In step ④, the controller modifies the correspondence between the throttle lever angle and the engine rotational speed in the overall machine control program to achieve the fan rotational speed target that meets the preset conditions.

[0014] In step ③, the method of selecting the fan rotational speed that meets the preset conditions is to compare the differences in the flow fields. When the simulation difference is less than or equal to the preset value, the corresponding fan rotational speed is selected.

[0015] The preset value is 5%.

[0016] In step ②, it is calculated through a one-dimensional overall machine performance calculation program.

[0017] In step ③, the simulation uses a three-dimensional CFD simulation of the afterburner.

[0018] The simulation difference is the difference in the flow field distribution or the difference in the combustion simulation results.

[0019] The beneficial effects of the present invention are as follows: By conducting afterburner performance tests after reducing the rotational speed at the ground test stand, it provides a basis for demonstrating high altitude performance in the improvement and modification design of the afterburner. Compared with the sector test, the test takes into account the actual working conditions at the inlet of the afterburner, and compared with the full ring and high altitude test stand tests, the test cost is significantly reduced. Description of the Drawings

[0020] Figure 1 is a schematic flow chart of at least one embodiment of the present invention;

[0021] Figure 2 is a schematic diagram of the relationship between the fan conversion rotational speed and the throttle lever angle in at least one embodiment of the present invention;

[0022] Figure 3 is the air flow rate change curve corresponding to different fan conversion rotational speeds;

[0023] Figure 4 is the bypass ratio change curve corresponding to different fan conversion rotational speeds;

[0024] Figure 5 are the total pressure change curves corresponding to the converted speeds of different fans;

[0025] Figure 6 are the total temperature change curves corresponding to the converted speeds of different fans. Specific embodiments

[0026] The technical solution of the present invention will be further described below, but the scope of protection is not limited thereto.

[0027] Example 1

[0028] As Figure 1 shown, a whole-machine test method for testing the high-altitude performance of an afterburner chamber. During the engine bench test, by adjusting the control plan of the relationship between the throttle lever and the whole-machine speed, the fan speed when the whole machine turns on the afterburner is reduced, and the afterburning performance test is carried out by controlling the throttle lever at this fan speed.

[0029] Example 2

[0030] Based on Example 1, the fan speed when the whole machine turns on the afterburner is reduced so that the fan speed of the whole machine when the afterburner is turned on is within a predetermined range to simulate the high-altitude inlet conditions.

[0031] Example 3

[0032] Based on Example 1, it includes the following steps:

[0033] ① Obtain parameters: Obtain the aerodynamic parameters at the inlet of the afterburner chamber's inner flow path, the aerodynamic parameters at the inlet of the afterburner chamber's outer flow path, and the engine throttle state performance parameters recorded at the whole-machine ground bench point under a certain state point in the high altitude of the simulation test;

[0034] ② Calculate the speed: Calculate the ground bench fan speed similar to the parameters of the high-altitude state point to be simulated;

[0035] ③ Select the available speed: Conduct simulation and select the fan speed that meets the preset conditions;

[0036] ④ Input control: Input the fan speed that meets the preset conditions into the controller through the control plan.

[0037] Example 3

[0038] Based on Example 1, in step ④, the controller modifies the correspondence between the throttle lever angle and the engine speed in the whole-machine control program to achieve the fan speed target that meets the preset conditions.

[0039] Example 4

[0040] Based on Embodiment 1, in step ③, the method for selecting the fan speed that meets the preset conditions is to compare the flow field difference. When the simulation difference is less than or equal to the preset value, the corresponding fan speed is selected.

[0041] Embodiment 5

[0042] Based on Embodiment 4, the preset value is 5%.

[0043] Embodiment 6

[0044] Based on Embodiment 1, in step ②, it is calculated by a one-dimensional overall engine performance calculation program.

[0045] Embodiment 7

[0046] Based on Embodiment 1, in step ③, the simulation is a three-dimensional CFD simulation of the afterburner.

[0047] Embodiment 8

[0048] Based on Embodiment 4, the simulation difference is the difference in flow field distribution or the difference in combustion simulation results.

[0049] Embodiment 9

[0050] Based on the above embodiments, the following steps are adopted:

[0051] 1. Given the aerodynamic parameters at the inlets of the afterburner inner and outer ducts at a certain state point in the high altitude that needs to be simulated and the engine throttle state performance parameters recorded at the ground test stand point of the whole engine, calculate the ground test stand speed close to the parameters of the high altitude state point that needs to be simulated through a one-dimensional overall engine performance calculation program (one-dimensional numerical simulation of the whole aeroengine);

[0052] 2. Respectively, for the speed conditions (test stand speed reduction points) selected in step 1 and the aerodynamic parameters at the high altitude state point, conduct a three-dimensional CFD simulation of the afterburner, compare the flow field difference. When the difference in flow field distribution or the difference in combustion simulation results is small (≤±5%), it is determined that this speed can simulate this high altitude state point;

[0053] 3. Input the obtained fan speed into the controller through the control plan table, that is, modify the correspondence between the throttle lever angle and the speed. The format of the control plan table is shown in Table 1, achieving the effect of turning on the afterburner at the set speed and conducting an afterburner performance test. After the speed reaches the intermediate state, the speed remains unchanged, as Figure 2 shown.

[0054] Table 1 Control Plan Table

[0055] Fan conversion speed (N1, hs%) Throttle lever angle / ° Engine state 80 65 Intermediate state 80 70 Small afterburner state 80 80 Partial afterburner state 80 ＞90 Full afterburner state

[0056] In summary, during the engine bench test, by adjusting the control plan of the relationship between the throttle lever and the overall engine speed, the fan speed when the overall engine turns on afterburner is reduced, so that the fan speed of the overall engine when the afterburner is turned on is within a certain range, to simulate the inlet conditions of quasi-high altitude (decreased air flow, low pressure, low temperature inlet), such as Figures 3 to 6 as shown, and at this speed, the afterburning performance test (including small afterburner, partial afterburner, full afterburner) is carried out through throttle lever control, realizing the simulation of the quasi-high altitude inlet conditions of the afterburner in the engine bench state, and achieving the purpose of understanding the high altitude performance by comparing the performance after speed reduction during the improvement and modification design of the afterburner.

Claims

1. An overall engine test method for testing the high-altitude performance of an afterburner, characterized in that: During the engine bench test, by adjusting the control plan of the relationship between the throttle lever and the engine speed, the fan speed when the afterburner is turned on for the whole engine is reduced, and the afterburning performance test is carried out through the throttle lever control at this fan speed; reducing the fan speed when the afterburner is turned on for the whole engine makes the fan speed of the whole engine at the time of afterburner turn-on within a predetermined range to simulate the quasi-high-altitude inlet conditions; It includes the following steps: ① Obtain parameters: Obtain the aerodynamic parameters at the inlet of the afterburner inner flow path, the aerodynamic parameters at the inlet of the afterburner outer flow path, and the engine throttle state performance parameters recorded at the ground bench point of the whole engine under a certain state point in the high altitude of the simulation test; ② Calculate the speed: Calculate the ground bench fan speed close to the parameters of the high altitude state point to be simulated; ③ Select the available speed: Conduct a simulation, and select the fan speed that meets the preset conditions; ④ Input control: Input the fan speed that meets the preset conditions into the controller through the control plan; In step ④, the controller modifies the correspondence between the throttle lever angle and the engine speed in the whole engine control program to achieve the fan speed target that meets the preset conditions; In step ③, the method of selecting the fan speed that meets the preset conditions is to compare the flow field difference. When the simulation difference is less than or equal to the preset value, the corresponding fan speed is selected.

2. The whole-machine test method for testing the high-altitude performance of an afterburner as claimed in claim 1, characterized in that: The preset value is 5%.

3. The whole-machine test method for testing the high-altitude performance of an afterburner as claimed in claim 1, characterized in that: In step ②, it is calculated through the one-dimensional whole engine performance calculation program.

4. The whole-machine test method for testing the high-altitude performance of an afterburner as claimed in claim 1, characterized in that: In step ③, the simulation adopts the three-dimensional CFD simulation of the afterburner.

5. The full-machine test method for testing the high-altitude performance of an afterburner as described in claim 1, characterized in that: The simulation difference is the flow field distribution difference or the combustion simulation result difference.

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