An electrothermal subassembly of a steam thruster for nanosatellites. The subassembly has an inlet port for the supply of the working mass, heat exchangers with containing ducts, at least one heating element, a supersonic micro-nozzle, and a plurality of rods forming a truss structure.

Electric resistance thermal propulsion systems that are configured to heat propellants for expulsion from a thruster using a heat exchanger that includes ultra-high temperature ceramics, such as hafnium carbide (HfC), are disclosed. The heating chamber may also be constructed from such materials. In operation, the electric resistance thermal propulsion system raises the temperature of the propellants that exit the heating chamber to expand in the nozzle to generate thrust. HfC, for example, has both metal and ceramic properties, and thus, it can conduct the electrical current. The higher the temperature, the higher the specific impulse that can be generated, and the electric resistance thermal propulsion systems can tolerate a much higher temperature than has been possible before with this type of thruster.

Dual mode engine for propelling spacecraft, including combustion chamber having flange end, open nozzle end, and enclosed chamber portion extending therebetween, propellant tank in fluidic communication with combustion chamber, electronic controller, power source operationally connected to electronic controller, and fluid flow motivator operationally connected to electronic controller and connected in fluidic communication with propellant tank. Engine has chemical propulsion portion with propellant inlet port operationally connected to combustion chamber and disposed adjacent flange end, ignition trigger electrode positioned in combustion chamber adjacent propellant inlet port and operationally connected to electronic controller and operationally connected to power source propellant inlet port fluidically connected to tank electric propulsion portion with two electrodes ionizing propellant positioned in combustion chamber adjacent nozzle end, plurality of attitude control thrusters operationally connected to electronic controller and in fluidic communication with propellant tank, and plurality of valves, each fluidically connected between attitude control thruster and propellant tank.

A conductive liquid-fed pulsed plasma thruster includes a first electrode having a conductive solid portion and a conductive liquid portion, a second electrode separated from the first electrode to define an ignition space therebetween, at least one electric insulator separating the first and second electrodes, and a conductive-liquid passage extending within the conductive solid portion through which the conductive liquid portion flows from an inlet to an outlet located at the ignition space. The first and second electrodes are configured so that a drop of the conductive liquid portion forms and grows at the outlet when the conductive liquid portion flows through the conductive liquid passage until the drop of the conductive liquid causes an arc discharge between the drop and the second electrode that ignites the drop to produce a plasma cloud that generates thrust when exhausted.

A circuit for igniting and sustaining an electron discharge includes an ignitor circuit. The ignitor circuit includes a high voltage transformer and a switch connected in series between a primary of the transformer and a DC source return. The switch is configured to receive a driving signal. A reset circuit is connected in parallel to the primary of the high voltage transformer. A first rectifier is connected in series between a secondary of the high voltage transformer and a keeper. A terminal of the secondary of transformer is connected to a cathode. The circuit for igniting and sustaining the electron discharge also includes a sustaining circuit having a current source with a return connected to a cathode and a second rectifier connected in series between the current source and the keeper.

The present disclosure relates to systems, devices, and methods for spacecraft propulsion. In an embodiment, the present disclosure relates to an apparatus comprising a heat exchanger body defining a plurality of propellant channels configured to contain a propellant, a central cavity configured to contain a working fluid and fluidically connected to a plurality of working fluid channels that extend along a radial dimension of the apparatus, and a nozzle fluidically connected to the plurality of propellant channels and configured to expel the propellant.

A mass propelled device includes an evaporation chamber and at least one nozzle. The evaporation chamber includes (i) at least one transparent substrate and (ii) a plurality of nanostructures disposed on a second surface opposite a first surface. The evaporation chamber receives light on the first surface and the plurality of nanostructures excites conduction electrons in response to the received light. The evaporation chamber heats propellent therein using the conduction electrons thereby generating heated propellant. The at least one nozzle produces thrust by exhausting the heated propellent from the evaporation chamber.