• Orificed Hollow Cathode

Spacecraft propulsion systems are essential to the accomplishment of missions. Magneto- plasmadynamic thrusters have shown great promise as potential options for next deep-space missions because of their effective propulsion and high thrust-to-power ratio. The hollow cathode, which acts as the major source of electrons to sustain and neutralize the main dis- charge for thrust generation, is essential to the operation of MPD thrusters. For the SX-3 MPD thruster system, this thesis offers a methodical approach to the design and optimization
of high-current orificed hollow cathodes using LaB
The fundamental goal of this research is to create a complete tool that simplifies the com-
plex design process while accommodating a wide range of cathode dimensions and discharge currents. To accomplish this purpose, a two-part modeling approach is applied. To begin, a zero-dimensional plasma model is used to investigate the plasma properties of the cathode. Second, a reduced-order lumped-parameter thermal model is used to describe the thermal be- havior of the cathode structure. Furthermore, two-dimensional axisymmetric Finite Element Analysis utilizing COMSOL Multiphysics is conducted to validate the predictions obtained from the simplified models. The FEM simulations provide detailed insights into the spatial distribution of temperature within the cathode, enabling a comprehensive understanding of the complex physical phenomena at play. The study focuses on examining the influence of varying discharge currents (ranging from 50A to 500A) on critical parameters such as insert region temperature, orifice region temperature, and cathode lifetime, with xenon propellant utilized in the analysis. In summary, this research contributes to advancing the state-of-the- art for designing and optimizing high-current orificed hollow cathodes.