An experimental study on the heat transfer performance of a radiator using MWCNT-SiO2 hybrid nanofluid

Abstract

The study aims to investigate the effect of nanofluids on heat transfer through experimentation. To prepare the nanofluids, water, commonly used in radiator cooling systems, served as the base liquid. Multi-walled carbon nanotubes (MWCNT) and silicon dioxide (SiO2) nanoparticles were added at weight concentrations of 0.1%, 0.2%, 0.3%, and 0.4%, with two different flow rates tested. Sodium dodecyl sulfate (SDS) surfactant was used to prevent the nanoparticles from agglomerating. After visually observing the hybrid nanocoolant, it was found that SDS as a surfactant prevented sedimentation and maintained stability for two weeks. Furthermore, STEM imaging demonstrated that spherical SiO2 particles evenly distributed throughout the tube-shaped CNTs improved the fluid's thermophysical properties regarding heat transfer. Heat transfer improvements were assessed with water experiments. The findings indicate that greater nanoparticle weight concentration promotes heat transfer. The most significant improvement in thermal conductance (UxA) was recorded as 28% in the case of 0.4 wt.% MWCNT water-based nanofluid at 0.034 kg/s flow rate as against water. The economical performance of a nanoparticle-containing cooling system was gauged for a natural gas-powered engine.