Temperature Synchronization in Microchannel Cooling Systems

Microchannel evaporators are capable of removing large heat fluxes by taking advantage of the latent heat of phase- change. However, flow maldistribution in the parallel channels of the evaporator can cause a considerable variation in the cooling performance of each channel. Such variations in performance are undesirable and present a significant challenge to implement this strategy effectively. To address this issue, we analyze the fluid flow and heat transfer taking place in an evaporator consisting of two parallel channels. The computational model presented in this study quantifies the effect of thermal and flow coupling between the channels. The experiments characterize the performance of the evaporators with channels that are either thermally-coupled or thermally-decoupled. Our experiments and model indicate that flow oscillations with sufficient amplitude can aid in synchronizing the temperature across the channels that are thermally-coupled, flow-coupled, or both. Hence, with the simple strategy of allowing controllable flow oscillations, the performance of microchannel evaporators can be improved by mitigating flow maldistribution.