Characterization of Stability Regimes of Electrohydrodynamically Enhanced Atomization

A comparative analysis of the stability regimes of three di?erent electrohydrodynamic atomization (electrospray) systems is presented. Availability of a high resolution imaging system allowed for a direct visualization of the breakup mechanisms. Both liquid ?ow rate and applied voltage are varied in a large grid of values in order to build up a database of the observable jet breakup regimes. The exploited conditions have been chosen with the purpose of evidencing the relative in ?uences of geometrical, electrical and ?uid_dynamical e?ects at various working conditions. Experimental results shed light on the complex interaction between the controlling parameters and resulted in the formulation of some necessary conditions for the occurrence of stable jet regimes. The ®nal conclusion of the paper is the recognition of the actual limitation in the mass ?ow rate range where such regime can be sta- bilized. Nevertheless some suggestion comes for the exploitation of atomization condition di?erent from the classical Taylor cone jet that could be successfully exploited either in combustion systems or other technological application. Ó 2000 Elsevier Science Inc. All rights reserved.