Mathematical Modeling and Experimental validation of a Highly Efficient Flat Plate Solar Collector with compound Transparent Insulation Materials including a Silica Layer

Abstract

The present work consists in the development of a highly efficient solar thermal flat plate solar collector [FPC] with transparent insulation materials [TIM] at high-temperature ranges ( η at ∆T/G close to 0.1 Km 2 /W ). The emphasis of the research is set on determining the combination of insulation materials that can boost the overall efficiency at a reasonable cost. Thus, to assess the proportions of honeycomb and granulate silica aerogel layers. A collector without a high-temperature protection system is targeted regarding the previous versions. Additionally, a fast mathematical model is being developed to predict the collector's efficiency with a high degree of confidence with low computational effort based on parallel object-oriented simulation tools. The design is tested experimentally to prove the increment in its efficiency and confirm its reliability and durability. After the simulations, a silica layer of 1cm seems to boost efficiency but does not fully protect the TIM layer of 7.5cm since temperatures are estimated to reach above 165ºC in stagnation conditions. In contrast, the thickest layer of silica simulated of 3cm decreases the temperature reached in the TIM layer by a ∆T of 30K. Thus, a overheating protection systems appears to be mandatory in any case. The experience obtained will be used to improve the next generation prototype.