Hydraulic And Thermal Performances Of Tree-Like Convergent Microchannel Heat Sinks

This paper proposes a kind of tree-like convergent microchannel heat sink (TCMCHS) and numerically investigates effects of the outlet-to-inlet width ratio α of the convergent microchannel, the width ratio of the inlet of the daughter microchannel to the outlet of the parent microchannel γ (D-P width ratio), the channel length ratio β, the initial branching number N, and the branching levels m on the maximum temperature Tmax, the total thermal resistance RT, the pressure drop ΔP and the coefficient of performance (COP) of the TCMCHS with rectangular channel cross-section under the size limitations of fixed total channel volume. The results display that both the maximum temperature and the total thermal resistance drop with the decrease of the outlet-to-inlet width ratio α; however, the pressure drop ΔP of TCMCHS first drops and then increases with the rise of the outlet-to-inlet width ratio α. The different influences of the outlet-to-inlet width ratio α on the hydraulic and thermal performances lead to first increased and then decreased COP with the growth of the outlet-to-inlet width ratio α. Moreover, the COP declines with the increasing length ratio β, initial branching number N and the branching level m, but first rises when α is small and then declines when α is large with the rising D-P width ratio γ. The findings of this paper provide a feasible scheme for the improvement of the thermal and hydraulic performances of MCHS by using tree-like convergent microchannel.