BACKWARD FACING STEP

The backward facing step is a well know benchmark calculation to test the ability of a numerical code to model sensitive recirculation zones in velocity dominated flow problems (high Reynolds number). Since such calculations require some stabilization method to guarantee wiggle free solutions, it is a good test to see if the recirculations zone is not suppressed by the stabilization method.

The first picture shows the results of the velocity profile. Behind the step the recirculation zone matches accurately the desired value.

The second picture displays the shear stress as found in the calculations. The main shear stress is, as to be expected, present in the narrow in-flow channel.