Effect of Operational Conditions on Cooling Performance of Pump-Assisted and Capillary-Driven Two-Phase Loop

摘要

As electronics advance and require higher power densities, the demand for efficient cooling methods increases.nBecause of high heat flux capability, two-phase cooling systems may be applied to cool a wide variety of newlynemergent technologies, such as power electronics seen in electric-drive vehicles.This paper presents the experimentalnresults of the cooling performance of a pump-assisted and capillary-driven two-phase loop, which uses a uniquenplanar evaporator.Water is used as theworking fluid. The evaporator is fed liquid by bothmechanical and capillarynpumping, while the vapor and liquid phases in the evaporator are separated by capillary force to prevent it fromnflooding. To reduce the heat leakage through the wall of the evaporator, stainless steel of a relatively low thermalnconductivity is used as evaporator enclosure material, while copper is used as the heater body material. This paperndiscusses the effects of various operation variables of the two-phase cooling loop, such as dynamic and stepwise heatninput, systempressure, liquid flowrate, and heat sink temperature on the cooling performance of the two-phase loop.nThe two-phase loop was tested up to 400 W (68:7 W=cm2n) and had a thermal resistance measured to be as low asn0:12 K u0001 cm2n=W.