A study of the effect of ultrasonic vibrations on phase-change heat transfer

Abstract

The present paper investigates the effect of ultrasonic vibrations on the melting process of a phase-change material (PCM). Furthermore, the present study considers constant heat-flux boundary conditions, whereas much of the previous research had adopted constant wall-temperature conditions. The experimental results revealed that ultrasonic vibrations accompanied the effects like agitation, acoustic streaming, cavitation, and oscillating fluid motion, accelerating the melting process as much as 2.5 times, compared to the rate of natural melting (i.e., the case without ultrasonic vibration). In addition, temperature and Nusselt numbers over time provided conclusive evidence of the important role of the ultrasonic vibrations on the melting phenomena of the PCM. © 2002 Elsevier Science Ltd. All rights reserved.