Abstract
Experiments were performed to study the geometric effects on the compressible rectangular cavity flows at Mach 0.33, 0.62, and 0.82. Typical characteristics of mean surface pressure distributions show a slight pressure variation near the front face, a local peak surface pressure ahead of the rear corner, and a low pressure immediately downstream of the cavity. The length-to-width ratio of a cavity has a strong effect on the recompression and downstream expansion near the rear face, and the Mach number effect is minimized. Surface pressure fluctuation distributions show a damping near the leading edge at a higher freestream Mach number, a minor peak near the middle of the cavity floor, an increase toward the cavity rear face, and a peak value immediately downstream of the cavity. The amplitude of the pressure fluctuations ahead of the rear face increases with the length-to-width ratio for transitional- and closed-type cavity flows, and the maximum of peak pressure fluctuations rises rapidly for the transitional cavity flows at higher length-to-width ratio.
