Pool Boiling Heat Transfer Using Nanofluids

Abstract

Nucleate pool boiling regime can be considered as one of the most effective ways to make a viable great amount of heat exchange in a relatively small area. To investigate the characteristics of HTC (Heat Transfer Coefficient) enhancement using nanofluids, pool boiling HTC experiments of two water – based nanofluids with alumina Al2O3and titanium TiO2 were performed using electrically heated flat plate and heating element made of stainless steel under atmospheric pressure.Systematic experiments were carried out with pure water and nanofluids containing, Al2O3 and TiO2 nanoparticles in different concentrations of (0.05w %, 0.1w %, 0.3 w%, and 0.5 w %). A comparison is made between nucleate boiling of pure water and a widely used correlation proposed in 1952 by Rohsenow is done. The results show good correspondence. Pool boiling heat transfer coefficient and phenomena of nanofluids are compared with those of pure water. The experimental results show increase in the heat transfer coefficient value and decrease in the surface superheat temperatures of heating element. This value increases with increasing nanoparticles concentration. The best nucleate boiling heat transfer performance enhancement is generally observed to be at Al2O3 nanofluid, compared to that of TiO2nanofluid and pure water.

Keywords

• heat transfer