Optimum thermal design of triangular, trapezoidal and rectangular grooved microchannel heat sinks

A three-dimensional numerical simulation is conducted to investigate the effect of geometrical parameters on laminar water flow and forced convection heat transfer characteristics in grooved microchannel heat sink (GMCHS). Four geometry variables which are; the depth, tip length, pitch and orientation of the cavities are taken into account in order to optimize the aluminum heat sink design. These geometric parameters could change the cavity shape from triangular to trapezoidal and then to rectangular shape. The governing and energy equations are solved using the finite volume method (FVM). The performance of GMCHS is evaluated in terms of Nusselt number ratio, thermal/hydraulic performance (JF) and isotherm and streamlines contours. The results showed that the trapezoidal groove with groove tip length ratio of delta = 0.5, groove depth ratio beta = 0.4, groove pitch ratio of psi = 3.334, grooves orientation ratio of zeta = 0.00 and Re = 100 is the optimum thermal design for GMCHS with Nusselt number enhancement of 51.59% and friction factor improvement of 2.35%. (C) 2015 Elsevier Ltd. All rights reserved.