The impact of changing drum rotation direction on fabric motion and drying performance in clothes dryers

Abstract

Fabric motion in tumble dryers, particularly the motion observed from the cross-section of the rotating drum, contributes significantly to the heat and mass transfer between textiles and the surrounding hot airflow. However, the wider picture for this process is not yet clear and requires further study. In this article, fabric motion with different drum rotation direction settings was analyzed experimentally to determine the effect of drum rotation direction on drying performance. A high-speed video camera was used to record the fabric motion during the entire drying process. The recorded movies were then processed, and the velocity and occupancy distributions of the tracer fabric and several motion indexes were analyzed by using OpenCV and Matlab. The results indicated that changes in the drum rotation mode cause significant variations in the dynamics of fabric motion in domestic tumble dryers across different drying conditions with variations in fabric size, drum rotation speed and load size. Constantly changing drum rotation direction plays an important role in enlarging the motion area and reducing the passive motion area, lifting the textiles up to a higher place and agitating the mixture inside the rotating drum. This means that the fabrics can be effectively scattered instead of tangling together, and because this drying condition provides more opportunities for them to be exposed to the surrounding hot airflow, it enhances convective heat and mass transfer within the drying chamber and reduces the formation of wrinkles on fabrics. This study could lead to new guidance for obtaining effective fabric motion patterns that lead to an optimal drying performance.