EFFECTS OF SIC AND GRAPHENE OXIDE NANOPARTICLE-COATED SURFACES ON QUENCHING PERFORMANCE

Quenching experiments were conducted to investigate the effect of deposition of SiC and graphene oxide (GO) nanoparticles on heat transfer during rapid cooling in vertical tubes. Temperature histories during quenching were measured for each test section to confirm the effect of the nanoparticle-coated layer on quenching performance. Boiling curves for each test were obtained by using the inverse heat transfer method. Quenching performance was enhanced similar to 20% to 31% for nanoparticle-coated tubes compared to the bare tube. Scanning electron microscope images of the inner surfaces of the tubes following the experiments were acquired, and the contact angles were measured to observe the effect of surface structures and wettability on quenching performance. In the case of tubes coated with GO nanoparticles for 900 s, quenching performance and critical heat flux (CHF) were enhanced although the contact angle increased. To confirm the surface effect on the enhanced quenching performance and CHF of GO nanoparticle-coated tubes, FC-72 refrigerant was used as the working fluid of the quenching experiment to reduce the wettability effect on the heat transfer.