Journal of Colloid and Interface Science, Vol.465, 26-32, 2016
Acoustically-controlled Leidenfrost droplets
Suppressing the Leidenfrost effect can significantly improve heat transfer from a heated substrate to a droplet above it. In this work, we demonstrate that by generating high frequency acoustic wave in the droplet, at sufficient vibration displacement amplitudes, the Leidenfrost effect can be suppressed due to the acoustic radiation pressure exerted on the liquid-vapor interface; strong capillary waves are observed at the liquid-vapor interface and subsequently leads to contact between the liquid and the heated substrate. Using this technique, with 105 Hz vibration frequency and 10(-6) m displacement amplitude of the acoustic transducer, a maximum of 45% reduction of the initial temperature (T-0 similar to 200-300 degrees C) of the heated substrate can be achieved with a single droplet of volume 10(-5) I. (C) 2015 Elsevier Inc. All rights reserved.