An opening blocking device for the constricted section of a hypersonic wind tunnel diffuser

Abstract

The invention discloses an opening blocking device for a constricted section of a hypersonic wind tunnel diffuser. The opening blocking device takes the incoming flow direction of the hypersonic wind tunnel as the front, and includes a lower sealing assembly located at the lower part of the diffuser constriction section for sealing the lower gap; and located at the upper part of the diffuser constriction section for sealing the upper part The upper sealing component of the gap; the lower sealing component includes a left cover plate and a right cover plate symmetrically installed on both sides of the lower gap, sliding toward each other along the outer wall of the diffuser contraction section can reduce the lower gap; plate, and the upper cover plate is clamped in the upper gap of the contracting section of the diffuser, and has a smooth transition with the contact end surface of the upper gap. The opening sealing device is low in cost and high in efficiency, and can reduce the gap in the shrinkage section of the diffuser according to the degree of interference between the model support mechanism and the diffuser, improve the range and quality of the uniform airflow area in the test section, and flexibly adapt to the needs of wind tunnel tests .

Description

technical field [0001] The invention belongs to the field of hypersonic wind tunnel equipment, and in particular relates to an opening sealing device for a constricted section of a hypersonic wind tunnel diffuser. Background technique [0002] Hypersonic wind tunnels often use an open free-jet test section, and the upstream and downstream of the test section are respectively connected to a nozzle and a diffuser. The hypersonic airflow is first injected into the ambient airflow in the test section from the outlet of the nozzle, and the jet interacts with the ambient gas to form a regular boundary between the uniform airflow area of ​​the test section and the ambient air. The gas flows through the aircraft in the uniform airflow area and then enters Diffuser, finally collected by the downstream vacuum tank. [0003] The hypersonic wind tunnel diffuser usually adopts the aerodynamic layout of "diffuser contraction section - straight section - expansion section". Disturbance, ...

AI Technical Summary

Problems solved by technology

[0004] However, the model support mechanism often interferes with the diffuser during the attitude change of the aircraft. In order to achieve the attitude change of the aircraft smoothly, it is necessary to cut and remove the profile of the contracted section of the diffuser located in the interference space, thereby creating a gap. Destruction of the converging section profile will adversely affect the performance of the diffuser

In addition, the high-speed air flow will also overflow from the gap of the diffuser contraction section and re-enter the test section, which will increase the ambient pressure of the test section, thereby compressing the uniform area of ​​the air flow in the test section, affecting the quality of the air flow in the uniform area, and even causing the flow field of the wind tunnel to be blocked

Images