A Simulation Approach to Investigate the Effect of Liquid Film Rings on Drying Performance
Last modified: 2016-11-30
Abstract
Drying is a key unit operation and is valuable in increasing shelf life of the products accompanied by ease of handling and transportation. It has widespread applications such as food, textiles, pharmaceuticals and electronic devices. To understand drying and transport phenomena of porous materials, Pore network modeling (PNM) is exploited due to limitations in continuum models. During the convective macroscopic drying, formation of liquid film rings greatly affects the process kinetics. The purpose of this study is to model the liquid rings and investigation of their effect on process kinetics and performance. The simulation results obtained from previous and new models are compared and presented as moisture profiles, drying curves, computation time and evolution of number of single throats and cluster number. It was found that, in new drying model 7.75% water is occupied by liquid rings. Drying time is 1.2 times shorter than the time of previous drying model without liquid rings. The breakthrough point is achieved much earlier therefore; the constant rate period (CRP) is 2.5 times longer than before. There is only one main cluster observed from this small network due to the new cluster labeling algorithm regarding the hydro-conduction due to the rings. The computational time obtained for the new simulation is much longer.