The effects of nanoparticles on pool boiling and critical heat flux

Abstract

The use of nanofluids, which are aqueous fluids containing nanoparticles, facilitates the ability to increase the critical heat flux (CHF) of a system. This study conducted pool boiling experiments at 50 °C and atmospheric pressure to examine the CHF features of CuO nanoparticles, Al₂O₃ nanoparticles, and a hybrid of Al₂O₃ and CuO colloids. Ni–Cr wire is used as the primary heating element. The concentrations of nanoparticles in the base fluid varied between 0.1 and 0.5 percent by weight, with each increase representing a doubling of the previous value. From a low of roughly 2%, the critical heat flow climbed by around 19% in each of the test conditions. The appearance of a nanofluid on the heating surface, which enhances surface wettability, is associated with an increase in CHF. The accumulation of nanoparticles on the surface of the heater also contributes to the increase in CHF. After attaining a peak at 17% at 0.2 weight%, the rate of CHF enhancement shown by hybrid nanofluid began to fall. These findings have important applications in thermal management systems used in nuclear reactors, electronics cooling, and other high-heat flow scenarios.