Rotary harrow total pressure test system and test method suitable for aircraft air inlet channel

Abstract

The invention discloses a rotary harrow total pressure test system and test method suitable for an aircraft air inlet channel. The test system comprises a total pressure harrow module, a rotating module and a driving device. The total pressure harrow module is driven by a driving device to rotate so that the pressure probe on the total pressure harrow can test the total pressure at different positions in the outlet of the air inlet channel in a pneumatic operation process. The system is simple in structure, small in size, wide in test range, high in quantization precision and rich in obtained data, avoids additional blockage of a test flow channel by traditional total pressure test systems such as a *-shaped harrow, a water-shaped harrow and the like and even adverse effects that the air inlet channel is not started, and solves the problems that the traditional total pressure harrow is fixed in structure position, single in data and the like. The test precision is greatly improved, the test cost is reduced, the influence on a test flow field is small, and the system is particularly suitable for a total pressure test with a small scaling model and a small flow channel area.

Description

technical field [0001] The invention belongs to the field of air inlet wind tunnel tests, and in particular relates to a total pressure test device for air inlet outlets used in wind tunnel tests. Background technique [0002] The intake port is responsible for providing sufficient capture flow to the downstream engine, and its performance has a decisive impact on the thrust and stability of the engine. The main evaluation indicators of the inlet performance are the recovery coefficient of the total pressure at the outlet of the inlet and the distortion index of the outlet flow field, that is, the quality of the outlet flow field. an important part of. Due to the limitation of the size of the wind tunnel and the experimental funds, the inlet test often adopts a scaled model, so a small change in the flow area of ​​the inlet test model will have a significant impact on the test state and test accuracy, and may cause further damage in severe cases. The airway does not start,...

AI Technical Summary

Problems solved by technology

This method has been widely used in wind tunnel tests and flight tests, but due to the limited number of total pressure probes installed, the "meter" word rake or "water" word rake cannot obtain the true distribution of the total outlet pressure. The error is large, especially for the measurement of outlet distortion

In addition, the traditional "rice" or "water" rake has a larger total frontal area, which obviously intensifies the degree of throttling at the outlet and has a greater impact on the flow field in the inlet. This situation is even more severe when the model size is small. as significant

In addition to the above unfavorable factors, due to the limitations of the structure of the traditional total pressure rake, the positions of the total pressure rake and the total pressure probe are fixed, so the circumferential angle of the total pressure data is fixed. Compared with the high cost of wind tunnel operation, a single experiment The data obtained are too limited and the economy is poor

Especially for the outlet distortion index that is concerned with the design of the inlet, a large number of experiments are required to obtain effective data, which is a huge loss in terms of personnel, material resources and time.

[0004] For example, the Chinese invention patent application with publication number 107917793A discloses a multi-row pressure measuring rake used in fluid mechanics experiments, but this multi-row pressure measuring rake structure only increases the number of spanwise probes, but also aggravates the flow path The clogging can easily have an adverse effect on the flow

In addition, the area occupied by the supporting and fixed structure itself is too large, exceeding the area of ​​the flow channel occupied by the Pozi rake, which will have a greater adverse effect on the flow channel

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