Dynamics of fabric and dryer sheet motion in domestic clothes dryers

• Published in: Drying technology Vol. 40; no. 10; pp. 2087 - 2104
• Main Authors: Jones, C. R., Corona, A., Amador, C., Fryer, P. J.
• Format: Journal Article
• Language: English
• Published: Philadelphia Taylor & Francis 12-07-2022; Taylor & Francis Ltd
• Subjects: Centrifuging; Driers; dryer ball; dryer sheet; Emission analysis; fabric motion; Fabrics; Granular materials; Granular media; Moisture content; Moisture effects; Movement; Particle tracking; Positron emission; Positron emission particle tracking (PEPT); Radial flow; Shearing; Sheets; Tracer particles; tumble dryer
• ISSN: 0737-3937; 1532-2300
• DOI: 10.1080/07373937.2021.1918706

Positron emission particle tracking (PEPT) has been used to investigate the motion of radioactively labeled tracer particles attached to fabrics and solid fabric enhancer (SFE) delivery articles, such as dryer sheets, in the domestic clothes dryer. This work examines the dynamics of motion within the dryer across a range of operating conditions. Six regions within the dryer drum are identified, demonstrating the range of movements experienced by items during tumbling. These show clear correlation with existing flow regimes describing behavior of granular media in rotating drums. Fabric motion is primarily cataracting to maximize the surface area of fabric available to interact with drying air in the falling region, with some conditions moving toward centrifuging or cascading flows. Movement in the axial direction was significantly slower than the primary radial flow. Dryer sheets were more prone to centrifuging than fabrics, with significant time spent in contact with the drum wall. Conversely, a wool dryer ball was more likely to cascade, spending time mixed into the top of a fabric bed which forms in the impact and lifting regions. Behavior in this bed is primarily determined by frictional interactions with the drum wall, which subsequently affects behavior in the 5 remaining regions. The most significant changes to this behavior were observed when changing fabric moisture content and volumetric fill ratio, with wet fabrics and smaller load sizes both exhibiting faster falling speeds and spending more time in the fabric bed. The changes were most significant in the lifting, falling and detachment regions, with varying acceleration and shearing likely to influence both fabric wear and SFE delivery.