Deformation of a nearly hemispherical conducting drop due to an electric field: Theory and experiment

作者：Corson L T; Tsakonas C; Duffy B R; Mottram N J; Sage I C; Brown C V; Wilson S K^*

来源：Physics of Fluids, 2014, 26(12): 122106.

DOI：10.1063/1.4903223

We consider, both theoretically and experimentally, the deformation due to an electric field of a pinned nearly hemispherical static sessile drop of an ionic fluid with a high conductivity resting on the lower substrate of a parallel-plate capacitor. Using both numerical and asymptotic approaches, we find solutions to the coupled electrostatic and augmented Young-Laplace equations which agree very well with the experimental results. Our asymptotic solution for the drop interface extends previous work in two ways, namely, to drops that have zero-field contact angles that are not exactly pi/2 and to higher order in the applied electric field, and provides useful predictive equations for the changes in the height, contact angle, and pressure as functions of the zero-field contact angle, drop radius, surface tension, and applied electric field. The asymptotic solution requires some numerical computations, and so a surprisingly accurate approximate analytical asymptotic solution is also obtained.

• 出版日期2014-12