Experimental investigation of heat transfer enhancement during quenching using carbon-based nanofluids

Nanofluids offer superior thermal properties compared to conventional fluids, making them ideal for heat transfer applications such as cooling systems. This study experimentally investigates the effect of adding carbon-based nanoparticles, such as multi-wall carbon nanotubes (MWCNTs), nanodiamonds (NDs), and graphene nanoparticles (GNPs), on the heat transfer performance in distilled water using a quenching setup at a near-saturation pool and atmospheric pressure. Nanofluids were prepared using a two-step method at concentrations of 0.01%, 0.025%, and 0.05% wt. with Gum Arabic (GA) added as a surfactant to enhance stability. Stability was monitored through photographic analysis, while SEM imaging provided detailed nanoparticle characterization on bare and quenched surfaces. Results demonstrated significant improvement in the minimum film boiling temperature (T min ), with nanodiamonds showing the highest enhancement: 29.90% at 0.01%, 23.38% at 0.025%, and 18.75% at 0.05%. GNPs followed, while MWCNTs showed the lowest improvements. The superior performance of NDs is attributed to their high thermal conductivity and the formation of a porous nanoparticle layer on the surface, which increases surface area and disrupts vapor layer formation more effectively. Comparison with existing literature confirms the enhanced performance and highlights the role of nanoparticle shape and concentration. This study provides valuable insight into the literature by investigating in-depth how the same material with various shapes can contribute to improving heat transfer efficiency.