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Al2O3-based nanofluids: a review.

Sridhara V, Satapathy LN - Nanoscale Res Lett (2011)

Bottom Line: These suspended nanoparticles can change the transport and thermal properties of the base fluid.As can be seen from the literature, extensive research has been carried out in alumina-water and CuO-water systems besides few reports in Cu-water-, TiO2-, zirconia-, diamond-, SiC-, Fe3O4-, Ag-, Au-, and CNT-based systems.The Al2O3 nanoparticles varied in the range of 13 to 302 nm to prepare nanofluids, and the observed enhancement in the thermal conductivity is 2% to 36%.

View Article: PubMed Central - HTML - PubMed

Affiliation: Ceramic Technological Institute, BHEL, Malleswaram Complex, Bangalore 560012, India. satpathy@bhelepd.com.

ABSTRACT
Ultrahigh performance cooling is one of the important needs of many industries. However, low thermal conductivity is a primary limitation in developing energy-efficient heat transfer fluids that are required for cooling purposes. Nanofluids are engineered by suspending nanoparticles with average sizes below 100 nm in heat transfer fluids such as water, oil, diesel, ethylene glycol, etc. Innovative heat transfer fluids are produced by suspending metallic or nonmetallic nanometer-sized solid particles. Experiments have shown that nanofluids have substantial higher thermal conductivities compared to the base fluids. These suspended nanoparticles can change the transport and thermal properties of the base fluid. As can be seen from the literature, extensive research has been carried out in alumina-water and CuO-water systems besides few reports in Cu-water-, TiO2-, zirconia-, diamond-, SiC-, Fe3O4-, Ag-, Au-, and CNT-based systems. The aim of this review is to summarize recent developments in research on the stability of nanofluids, enhancement of thermal conductivities, viscosity, and heat transfer characteristics of alumina (Al2O3)-based nanofluids. The Al2O3 nanoparticles varied in the range of 13 to 302 nm to prepare nanofluids, and the observed enhancement in the thermal conductivity is 2% to 36%.

No MeSH data available.


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Effect of temperature on thermal conductivity of Al2O3-based nanofluids. 21°C to 51°C, 1 φ% [7]; 21°C to 51°C, 4 φ% [7]; 20°C to 40°C, 2 φ% [20]; 20°C to 40°C, 1 φ% [20]; 27.5°C to 34.7°C, 2 φ% [13]; 27.5°C to 34.7°C, 6 φ% [13]; 27.5°C to 34.7°C, 10 φ% [13]; 52°C to 67°C, 1.25 φ% [15]; 52°C to 67°C, 2.75 φ% [15]; 52°C to 67°C, 4.25 φ% [15].
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Figure 6: Effect of temperature on thermal conductivity of Al2O3-based nanofluids. 21°C to 51°C, 1 φ% [7]; 21°C to 51°C, 4 φ% [7]; 20°C to 40°C, 2 φ% [20]; 20°C to 40°C, 1 φ% [20]; 27.5°C to 34.7°C, 2 φ% [13]; 27.5°C to 34.7°C, 6 φ% [13]; 27.5°C to 34.7°C, 10 φ% [13]; 52°C to 67°C, 1.25 φ% [15]; 52°C to 67°C, 2.75 φ% [15]; 52°C to 67°C, 4.25 φ% [15].

Mentions: The thermal conductivity of nanofluids is temperature sensitive compared to that of base fluids. The effect of temperature on water-based Al2O3 nanofluids is shown in Figure 6. Different groups measured thermal conductivity at different temperatures. Das et al. [7] varied temperatures in the range of 21°C to 51°C demonstrating an enhancement of 2% to 10.8% for the particle load of 2 vol.% and observed thermal conductivity enhancement of 9.4% as compared to 24.3% for 4 vol.% solids. The authors suggested that strong temperature dependence of nanofluid thermal conductivity is due to the motion of the particles. The larger sized particles used by Murshed et al. [20] resulted in enhancement similar to that reported earlier [7] indicating that the enhancement is due to the intensification of the Brownian motion of the nanoparticles by addition of a surfactant and the application of temperature. The general trend in Figure 6 of increased thermal conductivity enhancement with increased temperature is not in line with a very early report of Masuda et al. [15].


Al2O3-based nanofluids: a review.

Sridhara V, Satapathy LN - Nanoscale Res Lett (2011)

Effect of temperature on thermal conductivity of Al2O3-based nanofluids. 21°C to 51°C, 1 φ% [7]; 21°C to 51°C, 4 φ% [7]; 20°C to 40°C, 2 φ% [20]; 20°C to 40°C, 1 φ% [20]; 27.5°C to 34.7°C, 2 φ% [13]; 27.5°C to 34.7°C, 6 φ% [13]; 27.5°C to 34.7°C, 10 φ% [13]; 52°C to 67°C, 1.25 φ% [15]; 52°C to 67°C, 2.75 φ% [15]; 52°C to 67°C, 4.25 φ% [15].
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3211876&req=5

Figure 6: Effect of temperature on thermal conductivity of Al2O3-based nanofluids. 21°C to 51°C, 1 φ% [7]; 21°C to 51°C, 4 φ% [7]; 20°C to 40°C, 2 φ% [20]; 20°C to 40°C, 1 φ% [20]; 27.5°C to 34.7°C, 2 φ% [13]; 27.5°C to 34.7°C, 6 φ% [13]; 27.5°C to 34.7°C, 10 φ% [13]; 52°C to 67°C, 1.25 φ% [15]; 52°C to 67°C, 2.75 φ% [15]; 52°C to 67°C, 4.25 φ% [15].
Mentions: The thermal conductivity of nanofluids is temperature sensitive compared to that of base fluids. The effect of temperature on water-based Al2O3 nanofluids is shown in Figure 6. Different groups measured thermal conductivity at different temperatures. Das et al. [7] varied temperatures in the range of 21°C to 51°C demonstrating an enhancement of 2% to 10.8% for the particle load of 2 vol.% and observed thermal conductivity enhancement of 9.4% as compared to 24.3% for 4 vol.% solids. The authors suggested that strong temperature dependence of nanofluid thermal conductivity is due to the motion of the particles. The larger sized particles used by Murshed et al. [20] resulted in enhancement similar to that reported earlier [7] indicating that the enhancement is due to the intensification of the Brownian motion of the nanoparticles by addition of a surfactant and the application of temperature. The general trend in Figure 6 of increased thermal conductivity enhancement with increased temperature is not in line with a very early report of Masuda et al. [15].

Bottom Line: These suspended nanoparticles can change the transport and thermal properties of the base fluid.As can be seen from the literature, extensive research has been carried out in alumina-water and CuO-water systems besides few reports in Cu-water-, TiO2-, zirconia-, diamond-, SiC-, Fe3O4-, Ag-, Au-, and CNT-based systems.The Al2O3 nanoparticles varied in the range of 13 to 302 nm to prepare nanofluids, and the observed enhancement in the thermal conductivity is 2% to 36%.

View Article: PubMed Central - HTML - PubMed

Affiliation: Ceramic Technological Institute, BHEL, Malleswaram Complex, Bangalore 560012, India. satpathy@bhelepd.com.

ABSTRACT
Ultrahigh performance cooling is one of the important needs of many industries. However, low thermal conductivity is a primary limitation in developing energy-efficient heat transfer fluids that are required for cooling purposes. Nanofluids are engineered by suspending nanoparticles with average sizes below 100 nm in heat transfer fluids such as water, oil, diesel, ethylene glycol, etc. Innovative heat transfer fluids are produced by suspending metallic or nonmetallic nanometer-sized solid particles. Experiments have shown that nanofluids have substantial higher thermal conductivities compared to the base fluids. These suspended nanoparticles can change the transport and thermal properties of the base fluid. As can be seen from the literature, extensive research has been carried out in alumina-water and CuO-water systems besides few reports in Cu-water-, TiO2-, zirconia-, diamond-, SiC-, Fe3O4-, Ag-, Au-, and CNT-based systems. The aim of this review is to summarize recent developments in research on the stability of nanofluids, enhancement of thermal conductivities, viscosity, and heat transfer characteristics of alumina (Al2O3)-based nanofluids. The Al2O3 nanoparticles varied in the range of 13 to 302 nm to prepare nanofluids, and the observed enhancement in the thermal conductivity is 2% to 36%.

No MeSH data available.


Related in: MedlinePlus