Simulation of Performance of Thermal Energy Storage in a Solar Cooker
Finite element analysis was used to simulate the performance of thermal energy storage in a solar cooker which was fabricated by our team. This cooker stores solar energy in materials like sand for future use. It is inexpensive to construct and can be widely used in villages and urban areas. The cooker energy storage unit consists of a cubical solid block which contains sand as a solar-energy storage unit, along with conducting aluminum sheets for uniform heat distribution throughout the block. The block is enclosed in a uniform layer of insulation, except the cavities on the top surface to allow heating of the sand and as well as near the cooking pot. This heated sand can be used at night to heat a cooking pot which is centrally located in the storage box. A paraboloidal concentrator focuses solar radiation through a secondary reflector onto the central zone of the storage block through the cavity in the insulation. The storage is charged for a set period of time and heat is subsequently discharged to a pot during the night time. The effects on cooker performance are compared for various numbers of plates in the storage block. The temperature attained at various stages is studied for various models. This can be used to cook food in a slow manner and can be kept heated until night.