Effect of Electric Fields on Ice Adhesion to Metals

Dartmouth College, Hanover NH

Investigators

Abstract

0084622 Petrenko It was found recently that a small DC bias applied across an ice/metal interface can significantly modify the work of ice adhesion and interfacial shear strength. Depending on particular experimental conditions ice adhesion can be either significantly enhanced or almost eliminated by the DC bias. It is proposed to study the physical mechanisms that are responsible for these effects. The following three physical processes, which are capable of modifying ice adhesion and are the most probable mechanisms of the phenomenon will be studied in detail: 1. The electrochemical decomposition (electrolysis) of ice adjacent to electrodes. 2. Depression of the freezing point of water caused by intensive injection of ions from electrodes in the water. 3. Electrostatic energy stored in electric double layers on the ice/ metal interface. The inverse process of healing the interfacial damage caused by ice electrolysis will also be studied. The healing occurs due to mass transport in the ice quasi-liquid layer. Finally, Joule's heat generation and heat transfer will be measured. Experiments will be performed on pure and doped ices and on various electrode and substrate materials. Because of the project's multidisciplinary nature, a variety of experimental and theoretical methods will be applied. Among them are measurements of the work and strength of ice adhesion, several modes of scanning probe microscopy (SPM), optical spectroscopy of ions and atoms in water and ice, AC and DC electrical measurements of ice and water, and theoretical analysis. When completed, this research will provide fundamental knowledge of how direct currents and electric fields affect ice adhesion to metals. That basic knowledge can then be used in developing new de-icing and anti-icing technologies. ***