ARTICLE INFO In this work efforts have been made to develop the mixed mode forced convection solar grape dryer for grapes drying with thermal energy storage. The performance of the dryer has been investigated experimentally. Dryer is designed for capacity of 25 kg and consist of the flat plate collector based air heating system integrated with thermal energy storage which utilizes Paraffin wax (PCM) as phase change material. Effect of mass flow rate of air on moisture content, drying rate and

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... ying time with and without incorporation of thermal energy system has also been evaluated. Grapes are dried with developed solar dryer to check effect of air flow on drying time. The thermal efficiency of dryer has been evaluated with and without use of thermal energy storage system for grapes at different air flow rates. The raisins are tested for final moisture content and its nutrition value with the commercially available resins in the market. The result shows that drying of grapes is technically feasible in accordance with international norms for moisture content and nutrition value for raisins with reduced drying time. The moisture reduction of grapes obtained with developed dryer is from 80% to 20% in 24 sunshine hours with thermal energy storage system. Incorporation of thermal energy storage system reduces drying time from 30 sunshine hours to 24 sunshine hours for grapes with mass flow rate air 0.01484 kg/sec. Drying time reduction is observed with decrease in mass flow rate of air for grapes.