A correlation of maximum turbulent heat transfer coefficient in reattachment flow region

Abstract

A correlation of the maximum turbulent heat or mass transfer coefficient in the reattachment region of separated flow is proposed based on surveying thoroughly previous data and also on conducting heat transfer measurements. A newly proposed formula is expressed by h Rl λ =0.192( U sl v ) 0.665 Pr 1 3 in which h R , l, U s and Pr denote the maximum heat transfer coefficient, the streamwise distance from the separation point to the reattachment point, the velocity along the separated shear layer and Prandtl number, respectively. In the case of mass transfer, Pr and λ are to be replaced by Sc and D, which are the Schmidt number and diffusion coefficient, respectively. That formula is found to be valid in a range of 0.7 ⩽ Pr ⩽ 9, 0.6 ⩽ Sc ⩽ 2500 and 8 × 10 3 ⩽ U s l/ v ⩽ 2 × 10 6.