Method for controlling temporary flush type supersonic velocity wind tunnel with ejector function

Abstract

The invention provides a method for controlling a temporary flush type supersonic velocity wind tunnel with an ejector function. The method includes that when the wind tunnel is started, firstly, the total pressure of a gas collection chamber of an ejector is adjusted to be working total pressure, then the total pressure of a stable section is adjusted to be a running total pressure value of a wind tunnel test, and then the ejector is closed for carrying out the wind tunnel test; and after specified testing items are finished, the total pressure value of the stable section maintains the same, the ejector is started to adjust the total pressure of the gas collection chamber to be a working total pressure value in a closed-loop mode, then gas flow is cut off, after the total pressure of the stable section is reduced to a preset cutoff total pressure value, the ejector is closed, and then a whole air-blowing testing process is finished. Through the method for controlling the temporary flush type supersonic velocity wind tunnel with the ejector function, the impact load in a start-up process of the wind tunnel and the impact load in a cutoff process of the wind tunnel can be reduced effectively, safety of models, a balance and a wind tunnel system can be guaranteed, requirements of the balance on strength and rigidity in a designing process of the balance can be effectively reduced, sensitivity of the balance can be improved, and the accuracy of the measurement of the balance and the quality of testing data can be improved.

Description

technical field [0001] The invention relates to the field of supersonic wind tunnel flow field control, and the invention is suitable for a temporary supersonic wind tunnel with independent air supply for ejectors, quick opening / closing and closed-loop control of the total pressure of the ejector air collection chamber. Background technique [0002] When the temporary supersonic wind tunnel is started, in order to quickly establish the supersonic flow field and shorten the time for the model to vibrate strongly when the normal shock wave passes through the test section, the main inlet valve is usually opened quickly to increase the total start-up pressure of the wind tunnel (total start-up pressure greater than the total operating pressure), push the normal shock wave out of the test section, and then reduce it to the operating total pressure after the flow field is established to save energy; for the same purpose as above, in the process of wind tunnel shutdown, a quick shut...

AI Technical Summary

Problems solved by technology

The above methods have certain effects in ensuring model security, but they also have certain limitations.

One is the method of adding auxiliary devices to the model. How to effectively realize the retraction and sealing of the device and eliminate the interference to the supersonic flow field is relatively difficult; the second is that the delivery method has obvious advantages for slender bodies and small load models It is difficult to realize the model with large wingspan and large load; the third is to increase the geometric size of the balance. While increasing the strength and rigidity of the balance, the sensitivity of the balance is obviously reduced, and it is difficult to achieve accurate measurement of the aerodynamic force on the model. quality of wind tunnel test data

[0004] There is no other better method mentioned in domestic and foreign literature on how to more effectively reduce the impact load on the model during the start-up / shutdown of the wind tunnel in the temporary supersonic wind tunnel

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