Modeling instabilities of electrically driven jets under constant or variable applied field and non zero basic state velocity

We investigate the problem of instability of electrically forced axisymmetric jets with respect to temporally and spatially growing disturbances, within parameter regimes that affects the process of electrospinnning. Deriving a dispersion relation based on the relevant approximated versions of the equations of the electro-hydrodynamics for an electrically forced jet flow. For temporal instability, we find in the non-zero basic state velocity, the growth rate of the unstable mode is unaffected by the value of the basic state velocity. But, the basic state velocity affects the period of the unstable mode in the sense that it decreases the period, and the rate of increase of the frequency with respect to axial wave number increases with the basic state velocity. For spatial instability, we find that the growth rate of the unstable mode is dominated by the basic state velocity. The basic state velocity also affects the period of the unstable mode.