title: A Very Stable High Throughput Taylor Cone-jet in Electrohydrodynamics.
abstract: A stable capillary liquid jet formed by an electric field is an important physical phenomenon for formation of controllable small droplets, power generation and chemical reactions, printing and patterning, and chemical-biological investigations. In electrohydrodynamics, the well-known Taylor cone-jet has a stability margin within a certain range of the liquid flow rate (Q) and the applied voltage (V). Here, we introduce a simple mechanism to greatly extend the Taylor cone-jet stability margin and produce a very high throughput. For an ethanol cone-jet emitting from a simple nozzle, the stability margin is obtained within 1 kV for low flow rates, decaying with flow rate up to 2 ml/h. By installing a hemispherical cap above the nozzle, we demonstrate that the stability margin could increase to 5 kV for low flow rates, decaying to zero for a maximum flow rate of 65 ml/h. The governing borders of stability margins are discussed and obtained for three other liquids: methanol, 1-propanol and 1-butanol. For a gravity-directed nozzle, the produced cone-jet is more stable against perturbations and the axis of the spray remains in the same direction through the whole stability margin, unlike the cone-jet of conventional simple nozzles.
authors.affiliation: Sharif University of Technology, Department of aerospace engineering, Tehran, Iran.
authors.forename: M R
authors.initials: MR
authors.lastname: Morad
authors.affiliation: Sharif University of Technology, Department of aerospace engineering, Tehran, Iran.
authors.forename: A
authors.initials: A
authors.lastname: Rajabi
authors.affiliation: Sharif University of Technology, Department of aerospace engineering, Tehran, Iran.
authors.forename: M
authors.initials: M
authors.lastname: Razavi
authors.affiliation: Sharif University of Technology, Department of aerospace engineering, Tehran, Iran.
authors.forename: S R Pejman
authors.initials: SR
authors.lastname: Sereshkeh