Fluid flow in wall-driven enclosures with corrugated bottom

In this article, incompressible, continuum regime, viscous flow of Newtonian fluid in two-dimensional (2D) wall-driven enclosures consisting of regular, square shaped, corrugations on the bottom wall is studied numerically. Steady and consistent simulation results are obtained using kinetic theory based lattice Boltzmann equation method (LBM) and solution of Navier-Stokes equation based on fictitious domain method (FDM). First, numerical validation is performed by comparing LBM and FDM results for velocity profiles at particular sections inside the enclosures and vertical velocity gradient at the top of the corrugation cavity. Flow features are then compared for variations in Reynolds number, bottom-wall corrugation height and number of these corrugations. Further, complex eddy dynamics with respect to input parameters and geometry is discussed in detail. Flow transition Reynolds numbers showing distinct flow behavior are found. The numerical results obtained are verified and appear to be consistent with the previously published results for 2D flow inside slender and shallow cavity enclosures.