Experimental investigation of heat transfer characteristics of the hot surface using Al2O3–water nanofluids

An experimental investigation has been carried out to analyze the heat transfer characteristics of a hot vertical stainless steel foil by circular impinging jets of pure water and Al2O3–water nanofluids. The local heat transfer characteristics are estimated from the thermal images obtained from infrared thermal imaging camera (A655sc, FLIR System). Tests are performed for different Reynolds number (Re = 5000–12000), nanofluids concentration (Φ = 0.15%, 0.6%) and for a different nozzle to plate distance (l/d = 6, 12). The results indicated that the heat transfer characteristics of Al2O3–water nanofluids were better compared with water. Based on the investigation a correlation among various parameter, namely, Nusselt number (Nu), Prandtl number (Pr), nozzle to plate distance (l/d), Reynolds number (Re) and particle volume fraction (Φ) is presented.