Development of electrostrictive force-feeding sub-system for liquid pulsed plasma thrusters

An electrostatically driven pressure valve has been successfully developed based on the electrostrictive force, delivering propellant to the discharge chamber via an open-end conduit, free of any moving parts. The proof-of-concept unit has been built and demonstrated stable operation. It was shown that the conventional theory of electrostriction in liquid dielectrics is applicable for the device. The electrostatic pump has been designed for a coaxial liquid-fed micro pulsed plasma thruster prototype operating in the 1 - 2 J energy range. Active mass dosage capability is proven as a function of applied voltage and pump operational time, introducing a new class of electronically controlled feeding systems. Experimental measurements demonstrate a minimum achievable mass bit ranging from 77 to 164 ug using the voltage-controlled operation. Moreover, the pump is able to deliver up to 1 mg of propellant for a single shot. In addition to the active control, the mass flow rate can be passively adjusted by changing the capillary dimensions (radius and length), conduit material and the propellant dielectric properties.