Abstract:
In the first part, a theoretical model is proposed for the charging of droplets separating from the
tip of liquid jets or filaments, based on a previous hypothesis by Iribarnc and Mason. The charging
is attributed to a shearing of the electrical double layer at the liquid-air interface. Ordcr-of-magni-
tudc estimates arc presented, for different jet diameters and conductivities.
In the second part experiments are described, in which jets of water and aqueous solutions were
produced from capillaries and made to break regularly into droplets. By eliminating the streaming
current from the capillary, it was possible to measure the electrical charge separation occurring when
the drops break off from the jet. With a jet 0.26 mm in diameter, the charges arc in the order of 10-5
to 10~4 c.s.u.f per droplet, the sign depending on the breakup mode, with little dependence on the
conductivity of the liquid above 10—3 £T~1 m_*. Both sign and order of magnitude arc consistent
with theoretical predictions.
