Viscous contribution to the pressure for electroviscous potential flow analysis of capillary instability

Abstract

Viscous contribution for the Viscous Potential Flow (VPF) analysis of capillary instability with axial electric field at the interface of two viscous fluids has been analysed. In VPF, viscosity enters through normal stress balance and the effects of shearing stresses are completely ignored. To include the effect of shearing stresses, viscous pressure is included in normal stress balance along with irrotational pressure and it is assumed that the viscous contribution to the irrotational pressure will resolve the discrepancy between the tangential stresses at the interface. Stability criterion is given in terms of critical value of electric field. Various graphs have been drawn to show the effect of the parameters, such as electric field, inner fluid fraction, Ohnesorge number, conductivity ratio and permittivity ratio.