Executive Summary : | Application of a strong electric field through an electrolyte solution in a microfluidic system often leads to electrohydrodynamic (EHD) instabilities, which have been shown to exhibit chaotic dynamics at low Reynolds number. The reported theoretical and experimental studies on EHD instabilities have primarily focussed on instabilities driven by a constant DC electric field, in configurations that differ based on the inclination between the applied electric field and the conductivity gradient. The proposed project deals with theoretical stability analysis of EHD instabilities driven by a time-periodic AC electric field, as opposed to a DC electric field studied widely in the literature. This work is motivated by emerging empirical evidence of enhancement in EHD instabilities upon superimposing a time-periodic component over a DC electric field. The mathematical analysis of electro-hydrodynamic stability under periodic forcing differs significantly from that driven by a constant electric field. A comprehensive mathematical analysis of EHD instabilities driven by periodic forcing will not only help in explaining the experimental observations of enhanced EHD instability due to periodic electric field, but may also provide novel ways of inhibiting instabilities in microsystems where such instabilities must be avoided. |