Stability of a surface-charged viscous jet in an electric field (Q1289468)

The authors investigate the capillary instability of a surface-charged cylindrical jet in a longitudinal uniform electric field. The linear stability analysis of both axisymmetric and azimuthal periodic modes is performed, and stationary axisymmetric states are found. The authors obtain a system of equations with boundary conditions for the perturbed flow and, using the standard technique, derive the dispersion relation. The dispersion relation is investigated for the axisymmetric and azimuthal periodic modes. It is shown that in the case of transverse axisymmetric and azimuthal periodic bending perturbations, the jet is disintegrated into individual drops. The azimuthal periodic Bohr mode leads to the longitudinal separation of the input jet into two new jets, and the instability of axisymmetric modes can be completely suppressed by varying the dielectric properties of the fluid and the longitudinal electric field strength. As a result, in a strong longitudinal electric field the capillary instability of a surface-charged cylindrical jet may lead to the splitting of the jet.