Experimental investigation of thermal radiative properties of Al2O3-paraffin nanofluid. (1st January 2019)

• Record Type: Journal Article
• Authors: Wang, Qiushi; Wei, Wei; Li, Dong; Qi, Hanbing; Wang, Fuqiang; Arıcı, Müslüm
• Is Part Of: Solar energy. Volume 177(2019)
• Page Start: 420
• Page End: 426
• Publication Date: 2019-01-01
• Subjects: Thermal radiative properties -- Al2O3-paraffin nanofluid -- Absorption coefficient -- Reflectivity; Solar energy -- Periodicals; Solar engines -- Periodicals; 621.47
• DOI: 10.1016/j.solener.2018.11.034
• Languages: English
• ISSNs: 0038-092X

Abstract

Highlights: Thermal radiative properties of Al2 O3 -paraffin nanofluid were investigated. Influences of volume concentration, nanoparticle size, temperature, and optical path were investigated. Absorption coefficient of nanofluid at 0.01 vol% is 15.5 times higher compared to that of paraffin. Nanoparticle size has more influence on reflectivity than on absorption coefficient. Abstract: The thermal radiative properties of nanofluids have considerable contribution to the effectiveness of harvesting solar energy. In this work, the thermal radiative properties of Al2 O3 -paraffin nanofluid were experimentally investigated in terms of the influence of volume concentration, nanoparticle size, temperature and optical path. The transmittance spectrums of Al2 O3 -paraffin nanofluid were measured by a TU-19 FTIR spectrometer which was used for the calculation for the absorption coefficient and reflectivity of nanofluid. The experimental results show that Al2 O3 -paraffin nanofluid performs excellent ability to absorb solar energy compared to pure paraffin, with higher absorption coefficients increased up to 15.5 times at volume concentration 0.01%. The reflectivity of nanofluid is sensitive to nanoparticle size. When the nanoparticle size decreases from 30 to 10 nm the reflectivity of Al2 O3 -paraffin nanofluid reduces about 37.04%. With increasing temperature, the absorption coefficient of Al2 O3 -paraffin nanofluid increases and the reflectivity accordingly decreases.