SUPPRESSION OF AERODYNAMICALLY INDUCED CAVITY PRESSURE OSCILLATIONS.

Abstract

A flight test program was performed to gain further insight into the phenomenon of flow-induced cavity pressure oscillations and to evaluate the effectiveness of suppression concepts in eliminating or reducing the pressure oscillations. The cavities tested were rectangular. The flight speeds ranged from Mach number 0. 6 to 1. 3 at pressure altitudes of 3,000, 20,000, and 30,000 feet. The suppression devices included leading edge spoilers and deflectors and trailing edge ramps and deflectors. Several combinations of these were tested. The results indicate that the flow-induced pressure oscillations in a cavity of the dimensions tested and for the speed range tested can be significantly reduced with leading edge spoilers in conjunction with a trailing edge ramp.