A Method for Computing Three-Dimentional Viscous Diffuser Flows

Authors

Published in 1975

A method for computing three-dimentional turbulent subsonic flow in curved diffusers is described. An approximate set of governing equations is derived for viscous flows which have a primary flow direction. The derivation is coordinate invariant, and the resulting equations are expressed in terms of tensors. General tube-like coordinates are developed for a general class of geometries applicable to subsonic diffusers. The coordinates are then particularized to diffusers having superelliptic cross sections whose shape can vary continuously between a circle and a near rectangle. The necessary metric information is derived for these superelliptic tube-like coordinates. Techniques for numerical solution of these equations by forward marching integration from upstream starting conditions are outlined.