Delayed Coalescence on Solids and Liquids

By employing vibration of a viscous oil bath, one can inhibit the coalescence of oil drops and support them on an air cushion indefinitely as was shown by Couder et al., 2005. Herein we demonstrate that non-coalescence can be extended to solids by using soft gels where impacting water drops do not coalesce immediately because of the elasticity of the gel. Similarly, presence of surfactants can delay coalescence arising from the enhanced surface elasticity as noted by Kellay et al., 2001. Furthermore, vibrating the substrate, either soft gels or the surfactant baths, can then lead to an infinite time of coalescence expanding the regime of levitation to low viscosity liquids and even solids.