INVESTIGATION OF THE FLOW IN A RECTANGULAR CAVITY IN A FLAT PLATE AT A MACH NUMBER OF 3.55

摘要

An investigation has been made in the Mach 3.5 blowdown jet of the Langley High-Temperature Fluid Mechanics Section of the flow in a rectangular cavity in a flat plate. The results indicate that a criti¬cal value of the ratio of depth to chord length existed between 0.093 and 0.146 such that the pressure distribution in the cavity was very sensitive to depth changes for ratios of depth to chord length less than the critical value and was insensitive to depth changes for ratios of depth to chord length greater than the critical value. Span varia¬tions had large effects on the pressure distribution only in the narrow cavities (cavities having ratios of span to chord length less than 0.25) at the moderately shallow depth (ratio of depth to chord length equal to 0.093). Varying the upstream and downstream lip radii caused large changes in the pressure distribution only in the moderately wide (ratio of span to chord length equal to 0.75), moderately shallow cavity.nThe critical depth of the cavity and the pressure distribution in the very shallow cavity (ratio of depth to chord length equal to 0.042) were predicted analytically over the supersonic Mach number range, and the predictions agreed with experiment at a Mach number of 3.55.nThe boundary layer of the flow approaching the cavity was turbulent.