Experimental analysis on thermodynamic performance of clothes drying process under different fabric dynamic motion regimes in domestic tumble dryers

• Three fabric motion regimes (rolling, falling, centrifuging) in tumble dryers are characterized via drum speed adjustments. • Falling mode achieves highest energy efficiency and exergy efficiency. • Centrifuging mode shows lowest efficiency but largest exergy improvement potential. • Fabric-air contact area and motion uniformity critically influence drying kinetics and energy utilization. • Insights guide optimal drum operation to enhance domestic dryer sustainability and efficiency. This study presents a comprehensive energy and exergy analysis of a domestic tumble dryer to clarify its thermodynamic performance under different fabric motion regimes. Drying experiments were conducted at controlled drum rotation speeds to establish three distinct regimes: rolling (30 rpm), falling (45 rpm), and centrifuging (60 rpm). The performance was quantified using energy efficiency, energy utilization ratio, exergy efficiency, and exergy improvement potential. The falling regime demonstrated superior performance, requiring only 45.4 min and 2.3 kWh for drying 3 kg of textiles, with corresponding dryer and drying efficiencies of 53.1 % and 68.3 %, respectively. It also attained the highest average exergy efficiency for the drying process at 64.3 % and achieved the highest average EUR of 74.2 %, indicating superior utilization of the supplied energy. In contrast, the centrifuging regime was the least efficient, requiring 281.8 min and 12.0 kWh, with efficiencies of only 10.0 % and 12.4 %. Its exergy efficiency was the lowest (7.7 %), while its improvement potential was substantially higher (1751.8 kJ/h) than other regimes, highlighting significant inefficiencies and optimization opportunities. The findings conclusively demonstrate that optimizing fabric motion to promote complete dispersion, as exemplified by the falling regime, is a critical strategy for enhancing the overall energy and exergy efficiency of domestic tumble dryers.