A method for obtaining static pressure matching accuracy in uniform region of large-scale supersonic jet flow field

Abstract

The invention belongs to the technical field of high-speed free jet wind tunnel testing, and discloses a method for obtaining static pressure matching accuracy in a uniform region of a large-scale supersonic jet flow field. The method for obtaining the static pressure matching accuracy in the uniform region of the large-scale supersonic jet flow field of the present invention includes the following steps: arranging static pressure measuring points in the high-speed free jet wind tunnel; installing a cross total pressure on the moving measuring mechanism of the high-speed free jet wind tunnel Bent frame; start the high-speed free-jet wind tunnel; operate the high-speed free-jet wind tunnel by continuously varying the total pressure of the stable section; continuously collect relevant flow field parameters during the operation of the high-speed free-jet wind tunnel; close the high-speed free-jet wind tunnel; data processing to obtain the best static pressure matching accuracy. The method for obtaining the static pressure matching accuracy in the uniform region of the large-scale supersonic jet flow field of the present invention has simple and clear ideas, sufficient theoretical basis, and has engineering application value.

Description

technical field [0001] The invention belongs to the technical field of high-speed free jet wind tunnel tests, and particularly relates to a method for obtaining static pressure matching accuracy in a uniform region of a large-scale supersonic jet flow field. Background technique [0002] In traditional high-speed free-jet wind tunnels, when performing supersonic tests, the total operating pressure is usually increased to blow air, which can ensure uniform airflow at the rhombus-shaped area of ​​the nozzle outlet. However, the air flow will undergo repeated expansion acceleration and compression deceleration processes outside the diamond-shaped area and within the jet boundary, which makes the flow field quality outside the diamond-shaped area deteriorate sharply. The uniform airflow within the diamond-shaped area can be used for small-angle-of-attack air inlets, engine characteristics and other tests that require a smaller scope of the uniform area, and the model size cannot...

AI Technical Summary

Problems solved by technology

However, the range of the uniform flow field in the rhombic area is too small to meet the high-quality test requirements of the high-angle-of-attack inlet, the integration of air intake, airframe, and engine, thrust vector characteristics, and large-scale models.

[0003] The significant advantage of the high-speed free-jet wind tunnel is that the blockage of the model is allowed to be large, but the uniform area of ​​the supersonic jet flow field under the traditional operation mode is small, which limits the role of the high-speed free-jet wind tunnel

The static pressure matching point method can only adapt to the situation where the model state remains unchanged or changes slightly. Once the model state changes greatly, the matching pressure of the flow field needs to be changed accordingly to maintain a large uniform area in the supersonic flow field. scope

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