Study of incompressible separated flow using an implicit time-dependent technique

It is pointed out that accurate numerical simulation of high-Reynolds number incompressible separated flows poses a significant challenge even for simple two-dimensional configurations. An unsteady analysis which needs significant computer resources is required to study such flows numerically. For many physical configurations of engineering and scientific relevance, such as airfoils, diffusers, and turbomachinery cascades, the resulting unsteady separating-reattaching shear flows necessitate a true time-dependent analysis. The present investigation is, therefore, mainly concerned with the development of an efficient unsteady flow analysis. The developed analysis for the study of separated viscous flow uses the conservation form of the incompressible Navier-Stokes equations in generalized orthogonal coordinates so that the analysis is versatile enough to treat flow geometries of arbitrary shape. The numerical method developed uses central differences for all spatial derivatives and provides an accurate solution for flow inside a backstep channel.