CFD studies on different configurations of drying chamber for thin-layer drying of leaves

The design of a single air pass drying chamber used in tray dryers for thin-layer solar drying of fragile, heat-sensitive food materials such as edible leaves is a challenging task. It is essential to obtain good air distribution in all drying chamber designs to ensure uniform drying of the product. Simultaneous achievement of once-through air-side pressure drop and increase the moisture mass transfer rates are also important objectives of any heat and mass exchanger design. For obtaining these objectives in the dryer design, Computational fluid dynamics (CFD) is used as a tool for designing and theoretically testing different suitable air flow drying chamber configurations in the tray dryer. In this investigative research work, four different optimized geometries of the drying chamber for drying leaves are designed and evaluated theoretically from predicted performance by using ANSYS FLUENT software. The limiting air-side pressure drops and achieved dried output from various configurations are checked, assessed and presented in this work. The best configuration and construction detail are also highlighted. This generalized, proven, CFD procedure can be used for checking the performance of any similar transit type inter mass exchanger, to predict the best configuration in terms of mass transfer and pressure drop.