Applying CFD for Studying the Dynamic and Thermal Behavior of Solar Chimney Drying System with Reversed Absorber

This article provides numerical study of the solar chimney (SC) assembled with a reversed absorber and packed bed for the indirect-mode solar dryer. The present study was designed to determine the effects of using the SC in three configuration and physical proprieties of the packed (thickness and porosity) on the dynamic and thermal behavior of airflow. The results reveal that (1) using SC without storage material can increase the maximum mass flow rate up to 5%. However, integrating a storage material in the SC can improve the mass flow rate up to 32% during nighttime; (2) the use of a packed bed can decrease the crops temperature fluctuation until about 76% and increase the operating time of the solar dryer up to 12.5 hours rather than 10 hours in the case without packed bed; (3) increasing the porosity from 0.1 to 0.8 can increase the maximum temperature by about 10 degrees C.