The Preparation of Electrohydrodynamic Bridges from Polar Dielectric Liquids

Abstract

Horizontal and vertical liquid bridges are simple and powerful tools for exploring the interaction of high intensity electric fields (8-20 kV/cm) and polar dielectric liquids. These bridges are unique from capillary bridges in that they exhibit extensibility beyond a few millimeters, have complex bi-directional mass transfer patterns, and emit non-Planck infrared radiation. A number of common solvents can form such bridges as well as low conductivity solutions and colloidal suspensions. The macroscopic behavior is governed by electrohydrodynamics and provides a means of studying fluid flow phenomena without the presence of rigid walls. Prior to the onset of a liquid bridge several important phenomena can be observed including advancing meniscus height (electrowetting), bulk fluid circulation (the Sumoto effect), and the ejection of charged droplets (electrospray). The interaction between surface, polarization, and displacement forces can be directly examined by varying applied voltage and bridge length. The electric field, assisted by gravity, stabilizes the liquid bridge against Rayleigh-Plateau instabilities. Construction of basic apparatus for both vertical and horizontal orientation along with operational examples, including thermographic images, for three liquids (e.g., water, DMSO, and glycerol) is presented.

Macroscopic Self-Organized Electrochemical Patterns in Excitable Tissue and Irreversible Thermodynamics

“…At the critical transition from quiescence to excitation, amplifications and slowdown of oscillation are predicted. The video of Elmar Fuchs [3] show these oscillations beautifully in water bridges. We showed them in the intrinsic optical signal or red scatter [29] [70]- [72].…”

“…The main problem appears to be limitations of the mathematical methods. For example, a type of dissipative structure, that we believe is crucial for the understanding of all biology, is the electrohydrodynamic bridges (EHD) especially the water bridges studied by the group headed by Elmar C. Fuchs [3]. Water is the fundamental polar liquid in living organisms and the bridges are dynamic structures created by electrical and gravitational fields.…”

“…Second, this energy appears to be related to a macroscopic state of water that behaves optically as quasi-liquidcrystals do [13]- [15]. Apparently this energy can be dissipated as infrared radiation [4] [16] or mechanical flow [3] [17]. We will propose that this energy from dissociated water is an important part of blood flow in venules, the spread of action potentials in axons, the heart beat and spreading depression waves and other electrochemical patterns in the brain present in functional syndromes.…”

Extracellular matrix and its role in conveying glial/neural interactions in health and disease

“…And finally, in 2014 in a Gerald Pollack seminar at Galembeck's institute, we became aware of the polar liquid bridges studied by Elmar C. Fuchs' group (see Fuchs et al [19] and Wexler et al [74] or better watch their videos 2 ). The electrical energy stored in dissociated interfacial water can be expended in the forms of heat, non-Planck infrared radiation and coherent slow flow of charged dissociated water.…”

Magnetic resonance imaging of flow and mass transfer in electrohydrodynamic liquid bridges

“…Electrohydrodynamic (EHD) liquid bridges are a peculiar phenomenon which has recently come into focus as useful for studying the intersection of continuum and molecular scale interactions in liquid matter. EHD bridges are easy to produce, requiring only a low conductivity polar liquid, two reservoirs, and a high potential low current DC power source (Wexler et al 2014). These bridges can be formed by a number of polar liquids including water (Woisetschläger et al 2011), and in the latter case are referred to as floating water bridges (Fuchs et al 2007).…”