Enhancement of Pool Boiling Performance using SWCNT based Nanofluids: A Sustainable Method for the Wastewater Heat Recovery

Abstract

Heat extraction from wastewater is an important and challenging task in the industry. Performance of the heat extraction decreases mainly due to the boiling crisis. Researchers are using nanofluids as a better alternative for conventional base fluids. Nanofluids exhibit better performance due to higher thermo-physical properties. Thus, in this study, we used single-walled carbon nanotubes (SWCNT) for the boiling operation. In the experimentations, we used two types of heater surfaces; the first is bare heater surface, and the other is the SWCNT deposited heater surface. Then we compared the performance of both heater surfaces. The critical heat flux (CHF) value observed in the case of nanoparticle deposited surface is 2.14 MW/m² and theCHF value observed in bare heater surface is 2.26 MW/m². This observed increment in nanoparticle deposited surface promotes the smaller size of the bubbles at a rapid rate and reduction in bubble size occurs because of the increased surface roughness. The heat-transfer  coefficient is also 5 % more in the nanoparticle deposited surfaces than the bare heater surface.