APPROXIMATE TURBULENT BOUNDARY-LAYER DEVELOPMENT IN PLANE COMPRESSIBLE FLOW ALONG THERMALLY INSULATED SURFACES WITH APPLICATION TO SUPERSONIC-TUNNEL CONTOUR CORRECTION

摘要

Numerical solutions of the differential equation obtained from the momentum theorem for the development of a turbulent boundary layer along a thermally insulated surface in two-dimensional and in radial shock-free flow are presented in tabular form for a range of Mach numbers from 0.100 to 10. The solution can be used in a step¬wise procedure with any given distribution of favorable pressure gradients and for zero pressure gradients. Solutions are also given for use with moderate adverse pressure gradients. The mean velocity in the boundary layer is approximated -by a power-law profile. In view of the stepwise integration methods to be used, the exponent designating the profile shape can be varied along the surface between the integral fraction limits l/5 and l/ll through interpo¬lation. Agreement obtained between theoretical and experimental boundary-layer development in a supersonic nozzle at a nominal Mach number of 2 indicates the general validity of the approximations used in the analysis - in particular, the method of extrapolating low-speed skin-friction relations to high Mach number flows. The extrapolation method used assumes that the skin-friction coeffi-cients depend primarily on Reynolds number, provided that the den-sity and the kinematic viscosity are evaluated at surface conditions.