A SUPG-Finite Element study for conjugate heat transfer analysis in two-dimensional ribbed passages

In the present study, conjugate heat transfer predictions are performed for forced convection and natural convection in a twodimensional, vertical channel attached with surface mounted obstacles and having a solid wall of considerable thickness. The Streamline Upwind Petrov-Galerkin (SUPG) Finite Element (FE) method with Cartesian frame work is used for solving the equations governing Newtonian, viscous, laminar, timedependent, incompressible flow in fluid region where as Galerkin finite element method is used for analysis of heat conduction in solid region. The effect of isothermal boundary conditions for different Blockage Ratios (BR Ratio of channel height to rib height) has been investigated when Reynolds number (based on inlet length) is varying from Re = 500 to Re = 1500 for forced convection and Rayleigh number ranging from Ra = 10 to Ra =10 for natural convection. The enhancements of heat transfer due to the increase in recirculation bubbles upstream and downstream of the ribs entailing a better mixing are quantified. The results for local Nusselt number distribution, skin friction coefficient along the heated wall with obstacles and pressure distribution are presented and discussed. The working fluid is assumed to be air (Prandtl number, Pr = 0.71).