Abstract:

ESDU 83017 gives graphs of forebody volume coefficient and wave drag coefficient for various blunting radii on secant ogive forebodies of various geometries in the Mach number range 0.70 to 1.05. The wave drag was calculated using a program based on a modified version of the South-Jameson finite difference method for inviscid transonic flow around unducted axisymmetric bodies. It is assumed for such bodies that viscous effects are small so that wave drag is approximately equal to pressure drag which can be obtained by integrating surface pressure. Examples compare forebody pressure distribution and wave drag calculated by the program with wind-tunnel results, and reference is made to other such comparisons. Axial pressure coefficient data for these bodies are given in ESDU 83018, while data for spherically blunted tangent ogive forebodies are in ESDU 79004.