Laminar Mixed Convection of Large-Prandtl-number Nanofluids in Horizontal Tube
This paper describes an experimental investigation into combined forced and natural convection heat transfer for large-Prandtl-number nanofluids flow in a horizontal tube at low Reynolds number (9 < Re < 450). Silicon dioxide (SiO2) with diameter of 15 and 50 nm nanofluids with various particle concentrations (up to 2％ in volume) were used to investigate the effects of size and concentration of the nanoparticles to the convective heat transfer in laminar mixed flow regime. The effect of base fluid difference was illustrated by using two liquids of extremely dissimilar viscosities. The average Nusselt number measured increases with increasing the Reynolds number and Grashof number. By the inclusion of nanoparticles, the contribution of natural convection to the overall convective heat transfer can be either deteriorated under the same heat flux or enhanced under a given Grashof number. The huge increasing of the viscosity and Prandtl number were turned out to be the major reason for the observed deterioration and enhancement, respectively.
Laminar mixed convection heat transfer coefficient buoyancy force dynamic viscosity nanofluids
Zhao-Zan Feng Wei Li
Department of Energy Engineering, Zhejiang University, Hangzhou, Zhejiang 310027, PR China
国际会议
4th International Symposium on Heat Transfer and Energy Conservation(第四届传热与节能国际研讨会 ISHTEC2012)
广州
英文
1-5
2012-01-06（万方平台首次上网日期，不代表论文的发表时间）