Accession Number : AD0603503

Title :   VORTICITY AMPLIFICATION IN STAGNATION-POINT FLOW AND ITS EFFECT ON HEAT TRANSFER.

Descriptive Note : Interim technical rept.,

Corporate Author : BROWN UNIV PROVIDENCE R I

Personal Author(s) : Sutera,S. P.

Report Date : JUN 1964

Pagination or Media Count : 72

Abstract : Recently a mathematical model was proposed to demonstrate that vorticity amplification by stretching was an important mechanism underlying the sensitivity of stagnation-point heat transfer on cylinders to free stream turbulence. In this work a second, more general, case is treated in which the approaching flow carries vorticity of scale 1.5 times the neutral. By means of iterative procedures applied on an electronic analog computer an approximate solution to the full Navier-Stokes equation is generated. The heat transfer problem is solved simultaneously for Pr = 0.70, 7.0 and 100. It is found that a vorticity input which increases the wall shear rate by less than 3% is capable of increasing the wall heat transfer rate by as much as 40%. The sensitivity of the thermal boundary layer depends on Prandtl number. In the three cases investigated it is greatest for Pr = 7.0 and least for Pr = 100. (Author)

Descriptors :   (*HEAT TRANSFER, STAGNATION POINT), (*STAGNATION POINT, HEAT TRANSFER), (*VORTICES, STAGNATION POINT), MATHEMATICAL MODELS, FLUID FLOW, BOUNDARY LAYER, THERMODYNAMICS, PARTIAL DIFFERENTIAL EQUATIONS, ANALOG COMPUTERS, NUMERICAL ANALYSIS

Distribution Statement : APPROVED FOR PUBLIC RELEASE