The breakup length of harmonically stimulated capillary jets
A simple transfer function that can predict the breakup length of a pressure-modulated capillary jet is rigorously deduced from first principles. In this paper, the initial velocity modulation of a stimulated jet is given in terms of its pressure amplitude by means of a generalized Bernoulli equation, which in turn is connected to the breakup time through a two-mode linear analysis. The predicted breakup length is compared against experimental results with water jets emerging from a thin 1 mm-diameter orifice for different pressure modulations. These experiments agree better with the presented theoretical prediction than with a previously established model. ; Spanish Government under Contract No. FIS2011-25161 ; Junta de Andalucía under Contract Nos. P09-FQM-4584 and P11- FQM-7919 ; EPSRC-UK (Grant No. EP/H018913/1) ; Royal Society ; John Fell Oxford University Press (OUP) Research Fund