Numerical analysis of turbulent flow and heat transfer over a backward facing step: Comparison with experimental results

Numerical analysis of flow over a backward facing step is presented in this paper. The principal aim of this paper is to investigate some problems associated with the k-ε model in simulating turbulent flows. Dependence of the predicted reattachment length on the inlet conditions of k and ε is discussed. The strength of the k-l model in simulating turbulent flow problems is explored and its advantages over the k-ε model is presented. A new mixing length distribution based on the stream line pattern of the flow is presented for solving problems with recirculation. The study clearly indicates that for solving turbulent flow problems of industrial importance, in a cost-effective way, k-l model should be further evaluated.