Pool boiling of water-Al2O3 and water-Cu nanofluids on horizontal smooth tubes

Abstract

Experimental investigation of heat transfer during pool boiling of two nanofluids, i.e., water-Al2O3 and water-Cu has been carried out. Nanoparticles were tested at the concentration of 0.01%, 0.1%, and 1% by weight. The horizontal smooth copper and stainless steel tubes having 10 mm OD and 0.6 mm wall thickness formed test heater. The experiments have been performed to establish the influence of nanofluids concentration as well as tube surface material on heat transfer characteristics at atmospheric pressure. The results indicate that independent of concentration nanoparticle material (Al2O3 and Cu) has almost no influence on heat transfer coefficient while boiling of water-Al2O3 or water-Cu nanofluids on smooth copper tube. It seems that heater material did not affect the boiling heat transfer in 0.1 wt.% water-Cu nanofluid, nevertheless independent of concentration, distinctly higher heat transfer coefficient was recorded for stainless steel tube than for copper tube for the same heat flux density.

Nucleate pool boiling heat transfer of binary nano mixtures under atmospheric pressure around a smooth horizontal cylinder

“…For copper plate with nanofluids concentrations more than 0.0001%, the heat transfer coefficient was found to be less than that of the base fluid at both levels of surface roughness. On the other hand, for aluminum surfaces the heat transfer coefficient was found to be less than that of base fluid at every level of nanofluids concentration and surface roughness [22].…”

“…They discovered that adding a small amount of nanoparticles did not influence on boiling heat transfer rate, but addition of TiO 2 nanoparticles at 0.03% and 0.05% by volume deteriorated the boiling heat transfer [22]. Moreover, the boiling heat transfer coefficient decreased with increasing particle volume concentrations, especially at higher heat flux.…”

“…On the other hand, representing more details about quality of heated surface, such as purity and homogenization of surface, has been neglected in some works that strongly influence on surface temperature and heat transfer coefficient. Also Faced with these contradictions, it is obvious that a better understanding of the impact of nanoparticles on pool boiling heat transfer is required [1,22]. Fig.…”

The effect of pressure on heat transfer during pool boiling of water-Al2O3 and water-Cu nanofluids on stainless steel smooth tube

“…Copper nanoparticles, of a spherical form had a diameter from 7 nm to 257 nm; their mean diameter was estimated to be 48 nm according to the manufacturer (Sigma-Aldrich Co.). The photographs of the tested nanofluids are shown in Cieśliński and Kaczmarczyk (2011). The results of the thermal conductivity of the nanofluids measurements are discussed in Cieśliński and Kaczmarczyk (2011), as well.…”

“…Many aspects of pool boiling of nanofluids were investigated, among others the effect of concentration of nanoparticles (Das et al, 2003;Trisaksri and Wongwises, 2009), the effect of nanoparticle material (Cieśliński and Kaczmarczyk, 2011;Lotfi andShafii, 2009, Shi et al, 2006), the effect of heating surface orientation , material and finish (Cieśliński and Kaczmarczyk, 2011;Coursey and Kim, 2008), the effect of base liquid (Liu and Liao, 2008). Only a few publications are devoted to the effect of pressure on pool boiling heat transfer of nanofluids.…”