Aerodynamic Characteristics of Transonic and Supersonic Flow over Rectangular Cavities

An experimental and computational investigation has been performed to investigate flow characteristics and flow-field structures for three types of rectangular cavities. The data presented herein was obtained with cavity length to depth ratio of 6, 10 and 15 at 0° of attack, yawing and rolling angles of 0° over free-stream Mach numbers of 0.6, 0.8, 1.2 and 1.5 at Reynolds numbers of 1.23 ×107, 1.55 ×107, 2.01 ×107 and 2.26 ×107 per meter. The results indicate that the shear-layer expands over the cavity leading edge and impinges on the cavity floor for closed cavity flow, whereas it bridges the open cavity. The static pressure distributions are relatively uniform with the exception of a small adverse gradient occurring ahead of the rear face inside open cavity. Cavity length to depth ratio is a key geometrical parameter to define cavity flow types and influent pressure distributions inside cavities, and its decrease induces a decrease in pressure gradient. Increase in free-stream Mach numbers results in the trend that cavity flow types transform from closed to transitional cavity flow and from transitional to open cavity flow.