Mixed Convection in a Cavity with an Oscillating Moving Wall

A numerical investigation of unsteady laminar mixed convection heat transfer in a lid driven cavity of aspect ratio of 5 is performed. The forced convective flow inside the cavity is attained by a mechanically induced sliding lid, which is set to oscillate horizontally. The natural convection effect is sustained by subjecting the bottom wall to a higher temperature than its top counterpart. In addition, the two vertical walls are kept insulated. Discretization of the governing equations is achieved through a finite volume method. Fluid flow and heat transfer characteristics are examined in the domain at Richardson number, Grashof number and dimensionless lid oscillation frequency of:, , and S=0.001, 0.01, respectively the working fluid is assigned a Prandtl number of 0.7 throughout this investigation. Temporal variations of streamlines, isotherms, and Nusselt number are presented for various dimensionless groups. The results show that with decreasing the value of oscillation frequency, while Ri<1, the amplitude and the period of the rate of heat transfer oscillations increase.