Lattice Boltzmann Simulation for a Lid-Driven Cavity with Discrete Heating/Cooling Sources

The convective flow and heat transfer of nanofluids in a square lid-driven cavity have been analyzed numerically using a lattice Boltzmann method. First, the results of lattice Boltzmann simulation are compared with those available in the literature and the solution of the finite volume method for the present problem. Justified by satisfactory accuracy, the method is then applied to studying heat transfer characteristics with various arrangements of heaters and coolers on the walls in a lid-driven cavity. The top wall moves in its own plane either leftward or rightward. The vertical walls are heated/cooled fully or partially, and the horizontal walls are adiabatic. It is observed that the heater/cooler location plays a vital role in the flow pattern and consequently the characteristics of heat transfer, for which partially heated/cooled surfaces exhibit better performance than fully heated/cooled ones. Specifically, with asymmetric allocation of thermal sources and amoving plate that introduces forced convection, the heat transfer rate is enhanced due to the coherent fluid motion driven under symmetry breaking of the thermal flow pattern. Addition of nanoparticles may also enhance heat transfer characteristics, but the improvement appears not impressive, relatively, when the added volume faction is up to 4% in this study. The work thus proposes an intriguing design on the allocation of discrete sources, which will be helpful for designing structure of electronic components and coolants of various types.