Flows in Diffusers Interfered with Wake behind a Circular Cylinder

Abstract

Effects of the wake behind a cylindrical stay upon internal flows and performances of rectangular cross-sectional diffusers were examined. When a stay of a moderate diameter is set at an appropriate position in the passage, the flow separation is controlled effectively. This seems to be mainly attributable to the blockage effect of the stay, the displacement effect of the wake flow and the increment of the turbulent energy. As the result, the performance of the diffuser with a fairly large divergent angle is improved. The flow pattern and pressure recovery are also discussed theoretically in this paper.