Building water bridges in air: Electrohydrodynamics of the Floating Water Bridge

Abstract

The interaction of electrical fields and liquids can lead to phenomena that defies intuition. Some famous examples can be found in Electrohydrodynamics as Taylor cones, whipping jets or non-coalescing drops. A less famous example is the Floating Water Bridge: a slender thread of water held between two glass beakers in which a high voltage difference is applied. Surprisingly, the water bridge defies gravity even when the beakers are separated at distances up to 2 cm. In the presentation, experimental measurements and simple models are proposed and discussed for the stability of the bridge and the source of the flow, revealing an important role of polarization forces on the stability of the water bridge. On the other hand, the observed flow can only be explained due to the non negligible free charge present in the surface. In this sense, the Floating Water Bridge can be considered as an extreme case of a leaky dielectric liquid (J. R. Melcher and G. I. Taylor, Annu. Rev. Fluid Mech., 1:111, 1969).

Paper submitted to Physics of Fluids journal, an illustrative video is included with three experiments

Cited by in corpus (6)

• Why the Water Bridge does not collapse
• Experimental investigation of the stability of the floating water bridge
• Theory of water and charged liquid bridges
• Non-equilibrium thermodynamics and collective vibrational modes of liquid water in an inhomogeneous electric field
• Armstrong Liquid Bridge: Formation, Evolution and Breakup
• Reversed Currents in Charged Liquid Bridges