EFFECT OF PHASE-CHANGING MATERIAL ENCAPSULATION ON FLOW BOILING IN A MICROCHANNEL-BASED ELECTRONICS COOLING SYSTEM

摘要

Numerous innovative cooling solutions have been suggested to evade peak heat dissipation demand as part of efforts in developing effective self-contained cooling methods for high heat flux management in electronics cooling systems. Dynamic thermal modelling and simulation of a heat sink making use of subcooled flow boiling of water in a microchannel in the presence of a phase-changing material encapsulated inside a variable-area storage is presented here. The developed dynamic heat transfer model is based on the heat stored in phase-changing material, heat transferred by natural convection in addition to the subcooled boiling in the microchannel. Simulations have been performed, based on the solution of this heat transfer model, for a wide range of times varying heat input from the processor as well as mass flux admitted through the channel. The characteristics of subcooled boiling in the microchannel have been assessed in detail with and without the presence of latent heat storage. Analysis of the heat transfer response shows that the heat absorbed in variable-area latent heat storage helps to damp the wall superheat within the nucleate boiling regime as well as prolong the occurrence of critical heat flux in the microchannel.