Numerical analysis of heat transfer due to confined slot-jet impingement on a moving plate

Abstract

Convective heat transfer from a moving isothermal hot plate due to confined slot-jet impingement is investigated numerically. Two-dimensional turbulent flow is considered. The rectangular flow geometry consists of a confining adiabatic wall placed parallel to the moving impingement surface with the slot-jet located in the middle of the confining wall. The k − ε turbulence model with enhanced wall treatment is used for the turbulence computations. The problem parameters are the jet exit Reynolds number, ranging from 5000 to 20,000, the normalized plate velocity, ranging from 0 to 2, and the normalized distance of separation between the impingement plate and the jet exit, ranging from 6 to 8. The computed flow patterns and isotherms for various combinations of these parameters are analysed to qualitatively understand the effect of the plate motion on the heat transfer phenomena. The distribution of the local and average Nusselt numbers and the skin friction coefficients at the hot moving surface for above combinations of the flow parameters are presented. Results are compared against corresponding cases for heat transfer from a stationary plate. The analysis reveals that the average Nusselt number increases considerably with the jet exit Reynolds number as well as with the plate velocity. The average skin friction coefficient, on the other hand, is relatively insensitive to the Reynolds number but increases significantly with the plate velocity.