Simulation and Performance Evaluation of a Dual - operated Solar Cooking and Drying System for developing Countries

Solar Cooking and Drying System for developing Countries

Abstract

This paper presents performance evaluation of a dual operated passive solar cooking and drying system for an arid and semi arid region. The system has the ability to utilise a range of thermal storage materials including phase change material (PCM) and other locally available oils as the medium for energy storage. The stored energy could be used as a backup to extend the drying and cooking operation of the system during low solar insolation period and night time.
The system has been tested and evaluated in accordance to the figures of merits viz; stagnation temperature test (F ) and 1 water boiling test (F ) for both cooking and drying applications. The system was further tested using different thermal storage 2 materials including water, vegetable oil, wasted engine oil and selected PCM materials for solar cooking and drying applications. The results have shown that, the system could replace most of the current conventional cooking and drying systems in the arid and semi arid climates, and have ability to provide heat retention for up to 5 hours using 4 litres wasted vegetable and engine oils. The heat retention period could practically be further extended when PCM materials are used as a heat storage medium owing to its latent heat storage capability. Computational Fluid Dynamics (CFD) was used for the performance evaluation, the CFD simulation of the dual operated system have shown the optimum outlet duct positions for drying applications. The computated results have shown that dual operation could be best achieved by positioning the duct air outlet at the middle or a bit lower position of the dual operated passive solar drying and cooking system.