HYDRAULIC AND THERMAL PERFORMANCES OF TREE-LIKE CONVERGENT MICROCHANNEL HEAT SINKS

Abstract

This paper proposes a kind of tree-like convergent microchannel heat sink (TCMCHS) and numerically investigates effects of the outlet-to-inlet width ratio [Formula: see text] of the convergent microchannel, the width ratio of the inlet of the daughter microchannel to the outlet of the parent microchannel [Formula: see text] (D-P width ratio), the channel length ratio [Formula: see text], the initial branching number [Formula: see text], and the branching levels [Formula: see text] on the maximum temperature [Formula: see text], the total thermal resistance [Formula: see text], the pressure drop [Formula: see text] 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 [Formula: see text]; however, the pressure drop [Formula: see text] of TCMCHS first drops and then increases with the rise of the outlet-to-inlet width ratio [Formula: see text]. The different influences of the outlet-to-inlet width ratio [Formula: see text] on the hydraulic and thermal performances lead to first increased and then decreased COP with the growth of the outlet-to-inlet width ratio [Formula: see text]. Moreover, the COP declines with the increasing length ratio [Formula: see text], initial branching number [Formula: see text] and the branching level [Formula: see text], but first rises when [Formula: see text] is small and then declines when [Formula: see text] is large with the rising D-P width ratio [Formula: see text]. 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.