4E analysis of a novel hybrid double-pass solar air heater integrated with a latent heat storage unit: an experimental study
摘要
Ensuring a consistent air temperature for extended periods using a solar air heater remains challenging, especially under fluctuating solar radiation. This experimental study evaluates the performance of a novel hybrid double-pass solar air heater (HDPSAH) integrated with a latent heat thermal storage unit (TSU). The primary objective is to maintain a stable outlet air temperature and assess the impact of positioning an auxiliary heater in the U-turn section on the system's thermal behavior. A comprehensive analysis was conducted from energy, exergy, environmental, and economic perspectives. The findings indicate that incorporating the TSU effectively stabilized the outlet temperature at 54 ± 1.25 °C, extending heat availability by 1.5 h after sunset. The system reduced reliance on electrical energy to 18.65%, with a daily consumption of 1674.6 Wh. At a mass flow rate of 0.024 kg s−1, the HDPSAH achieved a thermal efficiency of 72.3% and an exergetic efficiency of 3.5%. Additionally, sustainability indicators, including the sustainability index, improvement potential, and relative CO₂ reduction potential, were recorded as 1.04, 0.709 kW, and 2.89, respectively, highlighting its environmental benefits, with an energy payback time of 0.48 years. Furthermore, the system demonstrated significant economic feasibility, with an investment payback period of 0.65 years, indicating that the proposed HDPSAH is a cost-effective and sustainable solution for various agricultural and industrial applications.