Diaphragm-free shock tunnel throat device and test method thereof

Abstract

The invention discloses a diaphragm-free shock tunnel throat device and a test method thereof. The throat device comprises a driven section, a piston supporting section and a throat section; a piston ring is arranged in the piston supporting section and moves front and back to form a moving cavity; and an air inlet through hole is formed in the round-tube-shaped air inlet cylinder protruding forwards from the throat section, an end socket is installed at the front end of the round-tube-shaped air inlet cylinder, the end socket and the piston ring form a ball head conical surface line sealing structure, and an inflation hole and a breathing hole which are communicated with the movable cavity are further formed in the throat section. During test, high-pressure test gas pushes the piston ring to move backwards, gas in a moving cavity is exhausted through a breathing hole, the piston ring impacts the front end face of the throat section, the piston ring and the spherical head conical surface line sealing structure of the sealing head lose efficacy, and the high-pressure test gas enters the shock tunnel throat through the gas inlet through hole. The throat device and the test method are simple and reliable, the test efficiency is high, and the damage to the test model and the test sensor on the test model is small.

Description

technical field [0001] The invention belongs to the technical field of shock wave wind tunnels, and in particular relates to a diaphragm-less shock wave wind tunnel throat device and a test method thereof. Background technique [0002] The reflection type shock wave wind tunnel is a pulse type wind tunnel that uses the shock wave to compress the test gas and generates the hypersonic test air flow through the steady expansion of the nozzle. The reflection type shock wave wind tunnel is composed of sequentially connected driving section, driven section, throat, nozzle, test section and other sections, in which the driving section and the driven section are separated by the main diaphragm, and the two diaphragms are separated The driven section and the throat, the driving section is filled with high-pressure driving gas, the driven section is filled with lower-pressure test gas, the nozzle and the test section are in a vacuum environment, and the test model is located in the te...

AI Technical Summary

Problems solved by technology

[0004] During the instantaneous cracking process of the main diaphragm and the secondary diaphragm and after they are opened, under the action of airflow pressure, slag or even flaps are prone to drop off, and the diaphragm residue moves downstream with the airflow at high speed, which can easily cause damage to the throat and the test model. damage

In addition, the high-temperature, high-pressure, and stagnant effective test gas generated at the inlet of the reflective shock tunnel nozzle lasts for a short time. After the effective test time, the driving gas flowing into the nozzle has a higher pressure and a longer duration. The test sensor on the model caused a long washout, shortening the life of the test sensor

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