Tri-Dimensional Numerical Analysis for Forced Convection over a Forward Facing Step

Abstract

A FINITE VOLUME DISCRETIZATION TECHNIQUE IS USED TO DEVELOP A NUMERICAL CODE TO SIMULATE THE FLOW STRUCTURES AND FORCED CONVECTION IN A FORWARD FACING STEP CHANNEL. THE VELOCITY FIELD AND PRESSURE DISTRIBUTION INSIDE THE COMPUTACIONAL DOMAIN ARE LINKED BY THE SIMPLE ALGORITHM. THE DUCT DIMENSIONS ARE DEFINED IN TERMS OF THE STEP HEIGHT, SUCH THAT THE ASPECT AND EXPANSION RATIOS ARE FOUR AND TWO RESPECTIVELLY. THE TOTAL LENGTH IN THE STREAMFLOW DIRECTION IS SIXTY TIMES THE STEP HEIGHT, WHILE THE STEP EDGE IS LOCATED TWENTY TIMES THE STEP HEIGHT AFTER THE CHANNEL INLET. THE BOUNDARY CONDITIONS AT THE CHANNEL INLET CORRESPOND TO A FULLY DEVELOPED FLOW AT A CONSTANT TEMPERATURE T0. THE HEATING CONDITIONS ARE THOSE OF CONSIDEREING THE BOTTOM WALL AT A HIGH CONSTANT TEMPERATURE (TW>T0) AND THE OTHER WALLS AS ADIABATIC ONES. RESULTS FOR THE LOCATION AND SIZE OF THE RE-CIRCULATING ZONES, AS WELL AS THE FLOW STRUCTURES AND TEMPERATURE DISTRIBUTIONS AT DIFFERENT PLANES INSIDE THE COMPUTATIONAL DOMAIN FOR THREE DIFFERENT REYNOLDS PARAMETERS ARE PRESENTED.