ZEROTH-ORDER, ELECTROHYDROSTATIC SOLUTION FOR ELECTROSPRAYING IN CONE-JET MODE

Liquid and charge emissions in steady regime from an electrified menis cus take place when its shape develops an almost conical point. A very thin and remarkably stable capillary jet emerging from the conical ve rtex breaks up into droplets, forming the so-called electrospary. The emission process is an extremely complicated electrohydrodynamic pheno menon which may be solved by performing a perturbation analysis which requires the knowledge of an electrostatic, zeroth-order solution for the shape of the electrified meniscus with a conical tip. In this work , the shape of these tip-ended, axisymmetric, electrified menisci is s olved for the first time assuming negligible space charge. The solutio n of this first-order, electrostatic problem yields not only the backb one result on a further perturbation scheme to solve the liquid and ch arge emission process, but also the old problem of that value of the p otential difference at which the liquid is to be connected in order to achieve a tip-ended shape, necessary to have electrostatic atomizatio n, as a function of the liquid properties and boundary geometry.