FLOW DYNAMICS OF LID-DRIVEN CAVITIES WITH OBSTACLES OF VARIOUS SHAPES AND CONFIGURATIONS USING THE LATTICE BOLTZMANN METHOD
Isac Rajan, D. Arumuga Perumal
Abstract
This work implements the emerging computational technique namely the Lattice Boltzmann Method (LBM) to a fluid flow problem of single sided lid-driven cavities with various shapes of obstacles placed in it. The numerical methodology employs the Single-Relaxation-Time (SRT) model applicable to low Mach number hydrodynamic problem for incompressible flow regime. Three geometrical shapes of the obstacles considered are circular, square, and elliptic. Cavity with obstacles exhibited remarkable circulation zones and structures in contrast to the classical lid driven cavity. The flow mechanics and the vortex dynamics are studied for various values of Reynolds Number (Re = 100, 400, and 1000). Due to the introduction of the obstacles, a strong induced vortex forms close to the obstacles and its size changes interestingly with the variation of Reynolds number, which is captured by LBM. Further the study is extended to examine the vortex phenomena induced by changing the position of the obstacles within the cavity. It is observed that the flow structures change dramatically with little change in the position of obstacle inside the cavity which helps to identify position with enhanced mixing characteristics.