Compared with the cavity model installed into the side wall of the wind tunnel, the cavity model located in the core-flow of the wind-tunnel has obvious advantages in simulating the thickness of the boundary layer. However, the core-flow cavity model suffers from the problems that the thickness of the approaching boundary layer is significantly higher than the theoretical estimate and the sound pressure level in the cavity is significantly lower than the numerical result, which seriously affects the accuracy of the test results. In the present study, effects of leading-edge shapes on cavity flow tests at the subsonic and supersonic speeds are comprehensively evaluated, using the technologies including boundary layer measurement, pressure fluctuation measurement and surface fluorescent oil flow. The C201 cavity model is investigated, whose leading-edge shape can be changed during the tests. The test results show that at the subsonic speed, the elliptical leading-edge helps to eliminate flow separation. The obtained approaching boundary layer thickness and sound pressure level distribution in the cavity is consistent with the calculated results. At the supersonic speed, the leading-edge of the small-angle wedge shape helps to avoid formation of detached shock waves. The research results could provide guidance for the design of cavity model shape, so that the adverse effects of leading-edge flow separations and detached shock waves on cavity flow tests can be avoided.
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