Evaluation of α-AL_2O_3-PW nanocomposites for thermal energy storage in the agro-products solar dryer

摘要

The shortage of fossil fuels and environmental pollution is one of the main issues of the recent century. One of the optimal ways to save energy resources is to use phase change materials for storing thermal energy. In this research, three types of AL(2)O(3)-PW nanocomposites were used to store solar thermal energy and use it in a solar dryer. Nanoparticles of AL(2)O(3) were combined in three levels of 0.5, 1 and 1.5% w / w with paraffin wax. Synthesized nano-composites were poured into steel pipes and were used to store solar energy. The results showed that by adding nanoparticles to paraffin, the thermal properties of paraffin are improved, and its thermal energy storage potential is increased. The maximum amount of absorbed thermal energy was 3393, 6109, 6445, and 6089 kJ, for composites with 0, 0.5, 1, and 1.5 (wt%) nanoparticles of AL(2)O(3), respectively. Also, the results showed that the time required to reach agro-products with equilibrium moisture is reduced by increasing the amount of AL(2)O(3) in the nanocomposite. Considering the cost-benefit economic discussion, the use of nanocomposites with 1 wt% nano-particles of AL(2)O(3) is recommended.