STUDYING FLOW AROUND ELLIPTICAL CONES,

An experimental investigation of three-dimensional transonic and supersonic flows past elliptic cones in an aerodynamic wind tunnel is presented. Six models of elliptic cones with different eccentricities and half-cone angles were investigated. The results are presented in graphs and compared with available theoretical and experimental data obtained by many authors. The comparisons show that the nonlinear thinbody theory agrees satisfactorily with experimental data for slender elliptic cones in a limited range of M however, the theoretical values lie substantially lower than the experimental values, in proportion to the increases in flow velocity and cone width. Various methods used for calculating supersonic and hypersonic flows around conic bodies are reviewed, analyzed, and at times compared. Comparisons of methods such as tangential and equivalent-cone with the improved equivalent-cone method of Willi F. Jacobs show that the results of the first two agree satisfactorily with experiment only for bodies which do not deviate substantially from circular cones, though those obtained by the third method agree much better with experimental data. Optical investigations of all models at low M numbers showed that the shock fronts retain the same form of nearly circular cones and the local angle of the compression shock depends more on surface distribution along the body axis than on the shape of the body cross section. As the flow velocity increases, the shape of the shock wave in the section normal to the direction of flow approaches the shape of the body and the compression shock takes a conic, nonaxisymmetric form. Author