TY - JOUR
T1 - Experimental investigation of turbulent convective heat transfer and pressure loss of alumina/water and zirconia/water nanoparticle colloids (nanofluids) in horizontal tubes
AU - Williams, Wesley
AU - Buogiorno, Jacopo
AU - Hu, Lin Wen
PY - 2008/4
Y1 - 2008/4
N2 - The turbulent convective heat transfer behavior of alumina (Al2O3) and zirconia (ZrO2) nanoparticle dispersions in water is investigated experimentally in a flow loop with a horizontal tube test section at various flow rates (9000 < Re < 63,000), temperatures (21-76°C), heat fluxes (up to ∼ 190 kW/m2), and particle concentrations (0.9-3.6 vol % and 0.2-0.9 vol % for Al2O3 and ZrO2, respectively). The experimental data are compared to predictions made using the traditional single-phase convective heat transfer and viscous pressure loss correlations for fully developed turbulent flow, Dittus-Boelter and Blasius/MacAdams, respectively. It is shown that if the measured temperature- and loading-dependent thermal conductivities and viscosities of the nanofluids are used in calculating the Reynolds, Prandtl, and Nusselt numbers, the existing correlations accurately reproduce the convective heat transfer and viscous pressure loss behavior in tubes. Therefore, no abnormal heat transfer enhancement was observed in this study.
AB - The turbulent convective heat transfer behavior of alumina (Al2O3) and zirconia (ZrO2) nanoparticle dispersions in water is investigated experimentally in a flow loop with a horizontal tube test section at various flow rates (9000 < Re < 63,000), temperatures (21-76°C), heat fluxes (up to ∼ 190 kW/m2), and particle concentrations (0.9-3.6 vol % and 0.2-0.9 vol % for Al2O3 and ZrO2, respectively). The experimental data are compared to predictions made using the traditional single-phase convective heat transfer and viscous pressure loss correlations for fully developed turbulent flow, Dittus-Boelter and Blasius/MacAdams, respectively. It is shown that if the measured temperature- and loading-dependent thermal conductivities and viscosities of the nanofluids are used in calculating the Reynolds, Prandtl, and Nusselt numbers, the existing correlations accurately reproduce the convective heat transfer and viscous pressure loss behavior in tubes. Therefore, no abnormal heat transfer enhancement was observed in this study.
KW - Convective heat transfer
KW - Enhancement
KW - Nanofluids
KW - Thermal conductivity
UR - http://www.scopus.com/inward/record.url?scp=42549095595&partnerID=8YFLogxK
U2 - 10.1115/1.2818775
DO - 10.1115/1.2818775
M3 - Article
AN - SCOPUS:42549095595
SN - 0022-1481
VL - 130
JO - Journal of Heat Transfer
JF - Journal of Heat Transfer
IS - 4
M1 - 042412
ER -