Filling of charged cylindrical capillaries

摘要: We provide an analytical model to describe the filling dynamics of horizontal cylindrical capillaries having charged walls. The presence surface charge leads two distinct effects: It a retarding electrical force on liquid column and also causes reduced viscous drag because decreased velocity gradients at wall. Both these effects essentially stem from spontaneous formation electric double layer (EDL) resulting streaming potential caused by net capillary-flow-driven advection ionic species within EDL. Our results demonstrate that exhibits well-known linear Washburn regimes witnessed for uncharged capillaries, although rate is always lower than capillary. attribute this competitive success lowering driving forces (because electroviscous effects), in comparison effect weaker forces. further reveal time which transition between regime occurs may become significantly altered with introduction charges, thereby altering resultant capillary rather intricate manner.