Wave propagation on a charged surface of a cylindrical liquid column surrounding a long porous core

A mathematical model of wave propagation and instability on a charged surface of an infinite cylindrical column of a conducting fluid, surrounding a coaxial infinite porous core, is formulated and studied. The conditions are found under which the disturbances of the liquid column become unstable and result in its fragmentation into a chain of connected droplets. It is shown that the length of the droplets decreases with increase in the electric field.