Supersonic flow measurements in the body vortex wake of an ogive nose cylinder

Abstract

Abstract : This report covers an experimental investigation of the symmetric body vortex wake of a circular cylinder in supersonic flow. Flow field measurements were made in the cross-flow plane at various axial body stations for angles of attack from 10 to 25 degrees. Data were obtained for two Reynolds numbers at a freestream Mach number of 2 and for one Reynolds number at a freestream Mach number of 3. A conical pressure probe was used to measure total pressure, Mach number, and three orthogonal velocity components at a large number of grid points in each of the survey planes. The pitch and yaw angles of the probe were manipulated in the wind tunnel in order to minimize any probe interference effects on the body vortex. A new experimental technique was used which involved the interaction of a theoretical predictive technique, a computer driven probe, and real time data quality optimization. Results are presented for the distribution of total pressure, Mach number, cross-flow velocity field, and axial velocity component in the cross-flow plane. These quantities are further processed to infer the position of the primary body vortex in the cross-flow plane, local circulation distribution in the cross-flow plane, vortex core size, wake height, and total circulation in the cross-flow plane. (Author)