3D numerical study of thermofluid characteristics of a flat plate solar collector using nanofluid

Abstract

Solar collector generation is growing quickly around the world to lessen some of the negative environmental impacts of the heating sector. The variability of these renewable sources of heat possesses technical and economical challenges when integrated on a large scale. One of the potential solutions to deal with the variations of renewable energy sources, energy storage is being widely regarded. An elaborate theoretical study on thermofluid characteristics of a nanofluid filled flat plate solar collector (FPSC) has been presented in this thesis. The relevant governing equations have been solved by using finite element method. In this thesis numerical analysis has been performed for better understanding of the heat transfer phenomena of the flat plate solar collector using water as well as water/copper nanofluid. Both 2D and 3D models of the flat plate solar collector (FPSC) have been taken into account. Heat transfer and flow characteristics have been presented for various pertinent parameters. Then comparison in various forms has been shown to check whether 3D study is necessary or not. Two correlations for heat transfer rate and thermal efficiency have been developed from obtained 3D results. Higher heat transfer rate of 3%, mean output temperature of 1.6K and collector efficiency of 5% have been obtained in 3D analysis than that of 2D analysis. Not more than 2% solid volume fraction of water/copper nanofluid has found to be advantageous. Suitable mass flow rate has obtained 0.0248Kg/s from this numerical study. More heat transfer rate of 17% and thermal efficiency of 8% has found for using 2% concentrated water/copper nanofluid than base fluid in 3D simulation. Water based nanofluid having double nanoparticles (copper and silver) has also been used as heat transfer medium instead of nanofluid having single nanoparticle (copper or silver) in 3D study to observe whether thermal efficiency of FPSC increases or not. Also a quadratic form of thermal efficiency has been derived using the results obtained from current 3D numerical study and compared with a survey report for a good FPSC available in the literature.