Constructal Parallel-Flow and Counterflow Microchannel Heat Sinks with Bifurcations

Abstract

Based on the Constructal Theory, parallel-flow and counterflow microchannels heat sinks with bifurcations are put forward to manage the temperature nonuniformity and further reduce the temperature of microchannel heat sinks bottom plates. Several models with different lengths of bifurcations are designed, and the corresponding laminar fluid flow and heat transfer of all models have been investigated through numerical simulations. The pressure, velocity, temperature distributions, and averaged Nusselt numbers are analyzed in details, and then the overall thermal resistances and overall thermal performance are compared. The results show that the thermal performance of counterflow microchannel heat sinks is better than that of parallel-flow heat sinks for the same geometry, and bifurcation can improve the thermal performance for all cases. It is suggested that a proper design of the length of bifurcation counterflow microchannel can be employed to improve the overall thermal performance of microchannel heat sinks. The study complements and extends previous works.