Accession Number : AD0278579

Title :   APPLICATION OF SCHMIDT'S METHOD TO THE CALCULATION OF SPALDING'S FUNCTION AND OF THE SKINFRICTION COEFFICIENT IN TURBULENT FLOW

Corporate Author : BROWN UNIV PROVIDENCE R I

Personal Author(s) : KESTIN,J. ; PERSEN,L.N.

Report Date : DEC 1961

Pagination or Media Count : 1

Abstract : I NTIFIERS: Spalding function. The details of the numerical computation of the so-called Spalding function (ASME 1961, Part II: 39) which occurs in the theory of heat transfer across turbulent boundary layers, are described. The present calculation is confined to the case when the Prandtl number Pr = 1 and when the assumption of a constant turbulent Prandtl number equal to unity can be made. The method used is a modification of E. Schmidt's numerical scheme for the integration of the time-dependent, onedimensional Fourier equation of heat conduction. In the present case, the term which plays the part of thermal diffusivity depends on the analog of the space-coordinate and renders the equation singular at the origin. T e singularity is circumvented by making use of the fact that the temperature profiles must possess zero curvature at the wall. By the use of the Reynolds analogy for turbulent boundary layers it is shown that the prceding calculations can be used to obtain a relation between the skin friction coeffcient and the length Reynolds number for a flat plate wetted by a turbulent boundary layer. The integration is very simple and provides a method of judging the accuracy of D. B. Spalding's law of the wall. This turns out to be reasonably satisfactory. (Author)

Descriptors :   FUNCTIONS(MATHEMATICS), NUMERICAL INTEGRATION

Distribution Statement : APPROVED FOR PUBLIC RELEASE