Three-dimensional flow in cavity at yaw

Abstract

This study introduces a “building block” prototype model of three-dimensional (3-D) flows about protrusions and cavities with an arbitrary angle between the external flow and rigid elements. The considered flow in a 3-D cavity has the lid of cavity moving along the lid diagonal (Case A). The proposed case is taken as a typical representative of essentially 3-D highly separated vortical flows having simple single-block rectangular geometry of computational domain. This 3-D lid-driven cavity flow is studied by numerical solution of the 3-D viscous Navier–Stocks equations using FLUENT software with second-order upwind schemes for convective terms. Computational results are compared to the classical benchmark case where the lid moves in the direction parallel to the cavity side walls (Case B).The volume and plane integrals of momentum in the direction of lid motion and perpendicular to it are introduced to compare cases in a quantitative way. The integral momentum of the secondary flow (transverse to the lid motion) appears to be about an order of magnitude larger than that in Case B. In the proposed flow, the number and strength of secondary vortices depend substantially on the Re number of the flow whereas in Case B only one pair of secondary vortices appears for arbitrary Re number. For a rectangular 3-D 3:1:1 cavity, the integral momentum of the secondary flow in Case A is an order of magnitude larger than that in the Case B. The flowfield in Case A includes a curvilinear separation line and non-symmetrical vortices.