Modification of Performance in a 2D-Diffuser by an Incoming Turbulent Wake of a Circular Cylinder.

Performance of a two-dimensional diffuser is modified by means of an incoming turbulent wake of a circular cylinder installed upstream of the inlet of the diffuser. The pressure recovery coefficient and velocity distribution are measured under various combinations of the diameter and position of the circular cylinder. Reynolds number based on the inlet height and the velocity at the inlet of the diffuser is 4.7×104. The optimum combinations for improvement of the pressure recovery and reduction of loss are determined. Turbulent separation in the otherwise undisturbed diffuser is suppressed by using the optimum combinations.