Enhancement of heat transfer by water–Al₂O₃and water–TiO₂nanofluids jet impingement in cooling hot steel surface

Abstract

Two different nanofluids, namely waterÀAl 2 O 3 and waterÀTiO 2 , were impinged in the form of jet on hot steel surface to remove high heat flux, and their performance was compared. The dimension of the test steel sample was 120 mm £ 120 mm and 4 mm thickness. Four K-type thermocouples were embedded on the bottom surface of the plate to measure the transient temperature distribution. The time-temperature data were recorded by the help of a data acquisition system (make: CHINO, model: KR2000), and the results were analysed by ZAILA application software. Effect of impinging nanofluids with weight concentrations of 0.01%, 0.03%, 0.05% and 0.07% Al 2 O 3 and TiO 2 nanoparticles on heat transfer from the hot surface was tested. The surface heat transfer coefficient (HTC) was computed from the time-temperature history recorded during experimentation. Experimental results revealed that addition of nanoparticles to the base fluid (water) surprisingly enhanced the heat transfer rate and HTC as expected. The heat transfer rate increased up to certain limit of nanoparticle concentrations, and then declined. Application of nanofluids for the steel strip cooling was found very effective in terms of heat transfer phenomena as compared to the conventional fluid cooling methods.

Optimization of spray parameters for effective microchannel cooling using surface response methodology

“…The convective heat transfer coefficient (h) is the proportionality coefficient between the heat flux (q) and the temperature difference between the surface and the coolant (Ts-Tc). The surface HTC (h) can be calculated from Equation 1 as used by Nayak et al [39].…”

The enhancement of laminar jet cooling effectiveness at very high surface temperature by using Al2O3 nanofluid as a coolant

“…In the research by Tie et al, 18 they disclose that the augmentation is also observed in case of multiple array jet cooling. In addition to the above, according to Nayak et al, 19 jet cooling performance is more effective if Al 2 O 3 nanoparticles of lower concentration are used. The information and the methodology discussed above still depicts that the achieved quenching rate is not suitable for fast quenching operation, although each parameter variation in the favorable direction of heat transfer shows augmentation.…”

Effect of Nano-Fluid Jet Impingement on Heat Transfer of Surfaces With Different Shapes

“…Experimental data were generated for nanofluids with Al 2 O 3 and TiO 2 nanoparticle weight concentrations of 0.01%, 0.03%, 0.05% and 0.07%. They found that the nanofluid prepared with Al 2 O 3 nanoparticles provided better heat transfer characteristics as compared to that of TiO 2 and DI water [23]. Jaware and Bhagatexperimentally investigated the heat transfer and fluid flow due to the impingement of vertical circular single jet on a horizontal heated surface.…”