Electrohydrodynamics of electrified liquid menisci and emitted jets

In the present paper the cone-jet mode of electrospray atomization of liquids is considered. The basic equations of electrohydrodynamics are formulated with allowance for the inertia, viscosity, electrical conduction, and surface tension of the liquid. The structure of an electrified conical meniscus and emitted jet is studied by perturbation methods at low Weber number flows. The self-consistent solution to the governing equations has been found in the meniscus, jet, and gas subdomains where the liquid inertia influence vanishes to the leading order. Distributions of electrohydrodynamic variables are investigated and a scaling law for the jet current is obtained. The description of the transition region lying between the meniscus and jet is discussed. (C) 1999 Elsevier Science Ltd. All rights reserved.