Abstract
In this work, we analyze the characteristics of periodic flows in non-isothermal viscous fluid over a heated block in the presence of thermal plates at Reynolds number ( Re = 100 ) . The unsteady, incompressible Navier-Stokes (NS) equations with suitable initial and boundary data in 2D are executed by the finite element technique using a highly refined hybrid mesh. The temporal discretization is performed by an implicit stable backward differencing in time and a stable choice of finite elements from the finite element library for spatial discretization. The discrete nonlinear system arising from this discretization is linearized by Newton's method and then solved through a direct linear solver PARDISO. For this forced convective study, the range of dimensionless parameters, namely, the Prandtl number (Pr) and power law index (n) , are varied from 1 to 10 and 0.6 to 1.4 with a low Grashof number varying as ( 1 <= Gr <= 10 ) to produce a forced convection regime, respectively. For the authentication, we have compared our results with the literature at a similar configuration. After simulation, the results accomplished in the velocity profile, pressure, isotherm contours, drag and lift coefficients (trajectory motion), average Nusselt number (Nu(avg)) , etc. are considered. For convergence of solution at low shear rate (n < 1) , crosswind stabilization (CWS) function has been incorporated. It is observed that Nu(avg) becomes oscillatory for the shear-thinning case (n < 1) , while for the shear-thickening cases (n > 1) , it converges to a single value. Furthermore, the drag (C-D) and lift (C-L) coefficients are more pronounced for shear-thinning cases (n < 1) as compared with shear-thickening cases (n > 1) .