Numerical investigation of phase change material assisted indirect solar dryer for food quality preservation

Abstract

High temperature and direct sunlight due to tropical climatic conditions in India causes excessive heating in traditional solar dryer or open air sun drying process. Due to this, loss of nutrients and browning of the food products occurs which leads to food quality deterioration. Present study aims at modelling of latent heat storage material integrated solar dryer which maintains drying chamber temperature between 50 ⁰C and 55 ⁰C. This study also assesses the Phase Change Material (PCM) implementation in different configurations to assess the impact on the drying temperature. The model is first validated and then detailed performance evaluation for PCM integrated solar dryer for hot and dry conditions has been carried out for drying different food products viz. ginger, hot yellow pepper, onion, sweet green pepper and tomato is carried out. This study assesses three different configurations of PCM incorporation within the solar dryer i.e. (Case 1) Conventional indirect dryer, (Case 2) Modified solar dryer with PCM inside collector and (Case 3) Modified dryer with PCM incorporation inside the drying chamber. The results show that, the required thermal condition for selected crops was maintained more efficiently by Case-3 compared to the other cases.

Keywords

• Computational fluid dynamics
• Phase change material
• Latent heat storage
• Solar drying
• Energy efficiency