Supersonic wind tunnel testing apparatus capable of generating high-frequency downstream disturbance

Abstract

The embodiment of the invention discloses a supersonic wind tunnel testing apparatus capable of generating high-frequency downstream disturbance, which relates to the field of aerodynamics, and can solve a problem that the disturbance frequency of a counter-pressure mechanism of downstream pressure disturbance. The supersonic wind tunnel testing apparatus can also simulate various forms of downstream periodic disturbance with various frequencies, and a requirement of considering both conventional counter-pressure disturbance and high-frequency disturbance in a shock wave motion characteristic test is met. The supersonic wind tunnel testing apparatus comprises a spraying pipe section (1), an equal straight section (2), a cam spindle (3), a cam spindle driving power device (4), a flow channel connecting section (5), a closed cavity connecting section (6), a closed bearing supporting component (7), upper and lower side spraying pipe profiles (8), pressure measuring points (9), a schlieren observation window (10), a stepping motor and control system (11), a coupling (12), an inner supporting rod (13) and a ball bearing (14). The supersonic wind tunnel testing apparatus is applicable to a supersonic wind tunnel experiment in which high-frequency periodic disturbance is generated at the downstream.

Description

technical field [0001] The invention relates to the technical field of aerodynamics, in particular to a supersonic wind tunnel test device for generating high-frequency downstream disturbances. Background technique [0002] In supersonic and hypersonic flows, geometric and aerodynamic airflow obstructions will generally generate shock waves, and the related shock waves and shock wave / boundary layer interaction flow fields are a basic flow field in the field of high-speed aerodynamics . In practical engineering applications, the interaction between the shock wave structure and the vortex flow caused by the downstream back pressure is still an important cause of aerodynamic noise. On the other hand, it will also cause structural fatigue damage, which will directly affect the design performance and safety of the aircraft. The shock wave and the pressure disturbance downstream of the shock wave / boundary layer interference structure are considered to be the dominant factors lead...

AI Technical Summary

Problems solved by technology

[0003] At present, most of the wind tunnel tests on the upstream shock wave structure for the downstream pressure disturbance are carried out under the condition of steady-state back pressure, and a small number of studies have considered the downstream pulsating back pressure condition, and only focus on the lower few hertz, the highest ten Backpressure pulsation frequency in Hertz order

However, in practical engineering applications, the pressure disturbance downstream of the shock wave often reaches 100 Hz or even higher frequency conditions; Mainly manifested in:

[0004] First, there is a lack of test devices that generate dynamic changes in the form of downstream pressure disturbances; second, in the existing small amount of experimental research under pulsating back pressure conditions, the back pressure frequency is realized in the form of a stepper motor driving the back pressure cone to move along the flow direction Or the closed form of the sloping plate can achieve a low back pressure disturbance frequency, only a few Hz, up to a dozen Hz; third, there is a lack of devices that can achieve a wider back pressure pulsation frequency range

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