الفهرس 
SummaryOnly 14 pages are availabe for public view
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Abstract
To enhance the heat dissipation process from the silicon layer in low-concentrator polycrystalline solar photovoltaic system, several methods are examined. In the first step, a new cooling technique for concentrator photovoltaic (CPV) systems is developed using various configurations of microchannel heat sinks. Five distinct configurations integrated with a CPV system are investigated. The investigated heat sinks include a wide rectangular microchannel, a single layer parallel- and counter- flow microchannel, and a double layer parallel- and counter- flow microchannel. Based on the computational fluid dynamic results, the temperature contours on a plane located at the mid-thickness of the silicon layer are presented at different operating conditions and heat sink configurations. Accordingly, the maximum local temperature can be detected and temperature uniformity can be accurately estimated. Furthermore, at a concentration ratio of 20, the CPV system integrated with a single layer parallel- flow microchannel heat sink configuration (B) achieves the highest cell net power, electrical efficiency, and the minimum cell temperature. On the contrary, at the same operating conditions, the use of a single layer counter-flow microchannel heat sink configuration (C) is found to be the least effective cooling technique. The results of this study can guide industrial designers to adopt compact heat sink configurations and simple designs in the manufacturing process of hybrid CPV-thermal systems. Further, non-traditional coolants like nanofluids, high thermal conductive nanoparticles dispersed in the base fluid, are used as coolants. The results showed that using SiC-water nanofluid is favorable for these applications in comparison to Al2O3-water nanofluid. Furthermore, a modified polycrystalline silicon solar cell structure is introduced to dissipate more heat from the silicon wafer. The Ethylene Vinyl Acetate (EVA) layer underneath the silicon used is replaced with a nanocomposite layer that includes an EVA matrix doped with Boron Nitride (BN) nanoparticles at different loading ratios. In addition, the Tedlar Polyester Tedlar (TPT) layer is substituted with a high thermal conductivity aluminum backing foil layer. The findings reveal that at a solar concentration ratio up to 3.5 where no external cooling technique is used, the modified cell attains a slight reduction in solar cell temperature compared to the conventional cell. On the other hand, at a concentration ratio of 20, where the solar cell is integrated with a microchannel heat sink, a significant reduction of cell temperature is observed compared to the conventional cell. It is found that at a concentration ratio of 20, and a coolant mass rate of 100 g/min, the maximum temperature of the modified cell with 60% BN and an aluminum back sheet is 66 °C, while the conventional solar cell temperature is 108 °C. Additionally, of the two cells, the modified solar cell produces the highest net power of 45 W, and achieves the highest electrical and thermal efficiency of 17.5%, and 70.8%, respectively. Meanwhile, the conventional solar cell produces 34 W, and attains an electrical and thermal efficiency of 13.5%, and 69%, respectively.