https://eva.fing.edu.uy/pluginfile.php/55828/mod_resource/content/1/kalogiru.pdf

Solar thermal collectors and applications

Evaluation of the effect of nanofluid-based absorbers on direct solar collector

This paper gives a comprehensive overview about the recent advances related with the application of the nanotechnology in various kinds of the solar collectors. Papers reviewed including theoretical, numerical and experimental up to date works related with the nanotechnology applications in the flat plate, direct absorption, parabolic trough, wavy, heat pipe and another kinds of the solar collectors. A lot of literature are reviewed and summarized carefully in a useful tables ( Table 1 , Table 2 , Table 3 , Table 4 , Table 5 , Table 6 , Table 7 ) to give a panoramic overview about the role of the nanotechnology in improving the various types of the solar collectors. It was found that the use of the nanofluid in the solar collector field can play a crucial role in increasing the efficiency of these devises. We think that this paper can be considered as an important link between the nanotechnology and all available kinds of the solar collectors. From the other side, further researches are required to study the effect of nanotechnology to enhance the solar collector industry over the next several coming years.

Applications of nanotechnology to improve the performance of solar collectors – Recent advances and overview

A comprehensive review on the application of hybrid nanofluids in solar energy collectors

Solar energy is one of the best sources of renewable energy with minimal environmental impact. A numerical study has been conducted to investigate the natural convection inside a solar collector having a flat-plate cover and a sine-wave absorber. The water-alumina nanofluid is used as the working fluid inside the solar collector. The governing differential equations with boundary conditions are solved by the penalty finite element method using Galerkin's weighted residual scheme. The effects of physical parameters on the natural convection heat transfer are simulated. These parameters include the number of wave λ and non-dimensional amplitude A of the sinusoidal corrugated absorber. Comprehensive average Nusselt number, average temperature, and mean velocity field for both nanofluid and base fluid within the collector are presented as functions of the parameters mentioned above. Comparison with previously published work is made and found to be in excellent agreement. The numerical results show that the highest heat transfer rate is observed for both the largest λ and A. In addition, the design for enhancing the performance of the collector is determined by examining the above-mentioned results. © 2012 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library (wileyonlinelibrary.com/journal/htj). DOI 10.1002/htj.21026

H. Soltau

Papers

Testing the thermal performance of uncovered solar collectors