JFET_V8_N3_RP1 Yasser Rihan Journal on Future Engineering and Technology 2230 – 7184 8 3 1 10 Simulation, Step, Turbulent Flow, Heat Transfer This paper deals with a numerical analysis to investigate the heat transfer and the fluid flow behavior in a rectangular channel with a horizontal step on one principal wall. A mathematical model is proposed to simulate the heat transfer process inside the heat exchangers. The model is based on the conservation equations of continuity, momentum and energy. The two equations of turbulence model ‘k-epcelon’ are also applied. The implicit scheme of finite volume method is used for solving the coupled differential equations with iterative procedure. Thereby, the degree of flow separation is varied by changing the step height. The step height ratio (b/H) ranging from 0.25 to 0.75. The Reynolds number ranges from 10,000 to 80,000. The results show that the local heat-transfer coefficients in the separated reattached and redeveloped regions are several times as large as those for a fully developed flow. In general, the increase of the heat transfer coefficient owing to flow separation is accentuated as the Reynolds number increases. The comparison between the presented model and previously published experimental data shows a good agreement. February - April 2013 Copyright © 2013 i-manager publications. All rights reserved. i-manager Publications http://www.imanagerpublications.com/Article.aspx?ArticleId=2216