| Abstract
| - When voltage is suddenly applied to vertical, parallel dielectric-coated electrodes dipped into a liquidwith finite conductivity, the liquid responds by rising up to reach a new hydrostatic equilibrium height.On the microfluidic scale, the dominating mechanism impeding this electromechanically induced actuationappears to be a dynamic friction force that is directly proportional to the velocity of the contact line movingalong the solid surface. This mechanism has its origin in the molecular dynamics of the liquid coming intocontact with the solid surface. A simple reduced-order model for the rising column of liquid is used toquantify the magnitude of this frictional effect by providing estimates for the contact line friction coefficient.Above some critical threshold of voltage, the electromechanical force is clamped, presumably by the samemechanism responsible for contact angle saturation and previously reported static height-of-rise limits.The important distinction for the dynamic case is that the onset of the saturation effect is delayed in timeuntil the column has risen more than about halfway to its static equilibrium height.
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