Vibration isolation via Leidenfrost droplets

The presence of a thin vapor layer sandwiched between the droplet and the high-temperature substrate is observed to absorb mechanical vibrations, which can be exploited for application in vibration isolation for microdevices that are sensitive to ambient vibration. In addition to a first demonstration of an effective reduction of the vibration displacement magnitude of a small platform that placed atop the Leidenfrost droplets, which are on top of the high-temperature substrate and subjected to a harmonic excitation, we show that the vibration displacement magnitude of the Leidenfrost droplet on the rectangular groove is significantly smaller as compared to that on the conical groove—under free or forced vibration. The vibration displacement of the platform at the resonance frequency of the Leidenfrost droplet can be further reduced by using multiple droplets. Additionally, via a simple spring-mass-damper model, the analysis shows that this Leidenfrost droplets based vibration isolation system can work more effectively by increasing the weight of the droplets. In the absence of the vapor layer, we observe that the vibration displacement of the platform at the resonance frequency of the droplets is increased by up to 62%, highlighting the important role of the vapor layer to reduce the transmission of mechanical motion from the substrate to the platform. (paper)