Energy efficient piezoelectrically actuated transducer for direct-contact ultrasonic drying of fabrics

Abstract

Current clothes drying technology is an energy-intensive process that involves blowing hot air across tumbling wet fabrics to evaporate water. To address the relatively low energy efficiency of this drying technique, a new cloth drying technology was proposed in our prior study. This technology utilizes high frequency ultrasonic vibrations to extract water from a fabric in the liquid phase, resulting in a dramatical reduction in energy consumption and drying time. A piezoelectrically actuated transducer was designed and fabricated. The transducer design was based on a piezoelectric actuator that excites axisymmetric resonant modes in a thin circular metal mesh. The device was constructed by bonding a piezoelectric ring to a thin metal mesh with a hole diameter of 120 µm. Test results demonstrated that the new ultrasonic transducer efficiently dried clothes at an order of magnitude lower resonant frequency compared with the previous commercial devices, 23 kHz versus 135 kHz. Also, the power consumption per area of the new transducer was an order of magnitude less than the commercial devices. Depending on operating conditions, the device was 3–24 times more efficient compared to the commercial ultrasonic transducers utilized in our prior ultrasonic clothes drying studies.

Keywords:

• Ultrasonic cloth drying
• piezoelectric transducer
• metal mesh
• energy efficiency

Acknowledgments

This work was sponsored by the U.S. Department of Energy's Building Technologies Office under contract no. DE-AC05-00OR22725 with UT-Battelle, LLC. We would like to acknowledge Mr. Antonio Bouza, the Technology Manager for HVAC and Appliances, for his support. The authors also would like to acknowledge support from Oak Ridge National Laboratory for its assistance.

Disclosure statement

No potential conflict of interest was reported by the authors.