Modeling and validation of a commercial gas-fired tumble dryer

Convective drying is one of the most energy intensive thermal processes. In convective textile drying, > 50%) of the input energy is typically lost to the surroundings. A transient, two-dimensional mathematical model of textile drying in a gas-fired tumble dryer was developed. Mass, momentum, and energy conservation were used to understand the heat and mass transfer phenomena occurring in and around the textiles within the dryer. A moving evaporation front is used to numerically simulate the drying process in the textile. The mathematical model was validated using experiments conducted on a commercial gas-fired tumble dryer. The performance of the distributed parameter and the lumped drying models showed similar agreement when predicting specific moisture ratio and drying efficiency. The 2-D model showed good agreement when predicting the exit temperature of the combustor and drum with average absolute deviations of 4.2% and 7.7%, respectively.