A method to obtain the static pressure matching accuracy of large-scale supersonic jet uniform region

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 area of ​​a large-scale supersonic jet. The method for quickly obtaining the static pressure matching accuracy in the uniform region of a large-scale supersonic jet of the present invention includes the following steps: arranging static pressure measuring points in a high-speed free jet wind tunnel; determining the total pressure in the stable section of the wind tunnel; Jet wind tunnel; after the high-speed free-jet wind tunnel runs stably, collect relevant flow field parameters; close the high-speed free-jet wind tunnel; data processing to obtain static pressure matching accuracy. The method of the invention for quickly obtaining the static pressure matching accuracy in the uniform area of ​​the large-scale supersonic jet is simple and clear in idea, has sufficient theoretical basis, takes into account the requirements of Mach number variation and the requirements of the pressure control performance of the wind tunnel, and helps to accurately obtain the high-speed free jet wind tunnel The supersonic jet static pressure matching accuracy has the engineering application value.

Description

technical field [0001] The invention belongs to the technical field of high-speed free jet wind tunnel tests, and in particular relates to a method for obtaining static pressure matching accuracy in a uniform area of ​​a large-scale supersonic jet. 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 tested for small-angle-of-attack intake ports, engine characteristics, etc., which require a smaller range of the uniform area, and the model size cannot exceed the sc...

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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