Flow Boiling Performance Evaluation of Recharging Microchannel

Abstract

Nowadays, miniaturization of high-performance electronic devices leads to higher heat generation, which needs efficient cooling to maintain device temperature below its operating temperature. This work proposed an efficient cooling technique using two-phase flow boiling in a recharging microchannel (RMC) and compared its performance with the conventional simple microchannel (SMC). A three-dimensional numerical investigation is carried out using the volume-of-fluid multiphase model and evaporation–condensation phase-change model in ANSYS Fluent V15. Water with mass fluxes of 100 and 500 kg/(m2·s) enters through the microchannel at inlet subcooling of 5 °C, whereas the substrate bottom surface is subjected to constant heat flux in the range of 10–40 W/cm2. The water saturation temperature is considered as 50 °C, corresponding to the saturation pressure of 12.352 kPa. Results reveal that the RMC shows enhanced heat transfer coefficient, reduced thermal resistance, reduced wall superheat, and reduced substrate temperature compared to SMC. Besides, the RMC shows a reduced pressure drop than the SMC at lower mass flux, whereas it shows an increased pressure drop at higher mass flux. The flow boiling instabilities can mitigate during the bubbly flow regime in RMC. This study suggests the possible application of flow boiling in RMC to cool high-performance electronic devices.