Efficiency analysis of solar drying system integrated with flat-plate solar collector and thermal storage units

Solar drying can address the issues of product quality and high energy consumption associated with open-air drying. However, the efficiency of solar drying largely depends on weather conditions, and the drying temperature in traditional solar drying systems can exceed the optimal temperature range for the products, affecting product quality. Herein, we design a solar thermal storage-drying system that integrates a flat-plate solar collector and thermal storage units, with the outlet temperature of the system subsequently analyzed through numerical simulation. The results show that the effective drying temperature range was maintained at 46 degrees C-64 degrees C, ensuring the drying temperature staying within the optimal range, preventing high temperatures from affecting the drying quality, and extending the nighttime drying time by 3-4 h. Additionally, it was calculated that drying 1.0 kg of carrots required 32.8 h, which is a 16.17 % reduction in drying time compared to the traditional solar drying system (36.9 h). The average drying efficiency of the solar drying system was found to be 11.24 %. This study provides important insights into the development of efficient solar drying technologies, underscoring the significant potential of integrating thermal storage units to greatly enhance the efficiency of solar drying systems.