Thermal behavior of a flat plate solar collector with simultaneous use of helically heat collecting tubes and phase change materials

Abstract The thermal energy storage (TES) system, not only can it save a great deal of energy, but it can extensively use for accommodating needs of renewable energy as well; Therefore, phase change materials (PCMs) can be applied as a TES system to meet the needs of solar energy in solar systems during their operation owing to the high heat of fusion. In this study, the impacts of helically corrugated heat collecting tubes and PCM on the thermal behavior of a flat plate collector (FPC) are experimentally investigated. The variations of outlet temperature of working fluid, and the increase in the thermal efficiency of the FPC are considered. The heat losses in the FPC by using helically corrugated heat collecting tubes decrease by about 39.8% in comparison to that by using plain heat collecting tubes. Results demonstrated that despite decreasing the output temperature of working fluid in the FPSC with PCM in the morning, hot water can be provided during the discharging process in the evening. The efficiency of the FPC increased from 41.5% to 48.9% by using PCM.