Impacts of edge seal material on thermal insulation performance of a thermally resistive photovoltaic glazing (TRPVG): CFD research with experimental validation

Abstract

A novel design of photovoltaic (PV) glazing technology called TRPVG is introduced within the scope of this research, and thermal insulation performance of TRPVG for different edge seal materials is evaluated through a well-known and reliable commercial software ANSYS FLUENT. For a typical TRPVG configuration, CFD results are compared with the experimental data, and a good accordance is achieved. Then, different potential edge seal materials are considered for TRPVG technology in terms of their impacts on thermal bridging and hence overall heat transfer coefficient (U-value) of entire glazing. Besides the plastic based edge seals, which are widely utilized in fenestration products, thermal superinsulation materials like flexible aerogel are also considered in the research to analyze their potential effects for reducing the U-value range of TRPVG. A recent experimental research indicates a U-value of 1.10 W/m2K in which unplasticised polyvinyl chloride (PVC-U) is considered as edge seal. The U-value from the CFD research for the said configuration is determined to be 1.19 W/m2K, which verifies the accuracy of the numerical analyses. Further investigations reveal that the U-value of TRPVG can be enhanced to 1.13 W/m2K only if PVC-U edge seal is replaced with aerogel. This can be attributed to the competitively low thermal conductivity of PVC-U material (0.19 W/mK) as an edge seal. The predicted U-values of TRPVG are reported to be 1.44 W/m2K for polymer seal, 1.32 W/m2K for glass fiber seal, 1.26 W/m2K for polycarbonate seal, 1.24 W/m2K for polyethylene seal, 1.20 W/m2K for acrylic seal and 1.18 W/m2K for epoxy seal.

Keywords

• PV glazing,U-value,CFD,Edge seal material,Thermal insulation,CFD

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