CFD Modeling on a Solar Thermal Energy Transfer Performances with Experimental Validations in a Water-Based Serpentine Photovoltaic-Thermal Collector

The Korea government announced an expansion of electricity generation ratio to 20% by 2030 from renewable energy. PVT (photovoltaic thermal) has a great potential to be used as a renewable and clean solar energy. In current article, in order to investigate and analysis solar thermal transfer performance in a water-based serpentine PVT collector, three-dimensional computational fluid dynamics (CFD) modeling was carried out using commercial code with ANSYS FLUENT 2019R3. The CFD modeling results were carefully validated with experimental data. The thermal efficiencies of CFD modeling results were in good agreement with experimental data as error scale from 1.4% to 5.76%. After this careful verification, the CFD modeling was also carried out to investigations of solar thermal energy performances by pitch sizes (40 mm, 60 mm, 80 mm, 100 mm, and 120 mm) and water inlet positions. Specifically, significant parameters of a useful thermal energy (Q_u), water outlet temperature, pressure drop, and Q_u/DP (useful thermal energy (ḿ‧Cp‧DT)/pressure drop (DP)) were numerically derived with the pith sizes and the water inlet positions. Given the selected significant parameters and by considering Q_u/DP, the optimal pitch size was found to be 80 mm, while it was shown that the optimal position for the water inlet was on the left side of the unit.