Conjugate mixed convection in a cooling duct

Abstract

This work reports a numerical study of the mixed convection in finned duct flow that occurs in heat sinks devices. The laminar flow is considered fully developed and the convection-conduction coupling is treated by a conjugated approach. The mathematical formulation of this problem is constituted by the mass, momentum and energy equations. This partial differential equations system is solved by the Galerkin finite element method, adopting a pressure Poisson equation to establish the pressure-velocity coupling and to obtain a mass conserving flow. It was studied the effect of duct aspect ratio on the heat transfer rate and friction coefficient. Also the influence of the fluid to wall conductivity ratio in the Nusselt number results was investigated. This analysis tool was shown appropriate for the optimization of electronic components air-cooled heat sinks.