This document aims to describe the state of the art and some basic physics of self-fieldMagnetoplasmadynamic Thrusters (MPDT), which constitute a very interesting technologyfor high power (Megawatt range) space propulsion. The Thesis starts discussingthe frame and expectations for electric space propulsion and the different categories ofdevices. Then, the operational principles and the literature background of MPDTs arebriefly reviewed.The central part of the Thesis is devoted to understand and model the plasma productionand acceleration processes in the MPDT chamber. A two-step progress is followed,materialized in two mathematical models. The first, the simplest one, describesthe axial acceleration of a fully-ionized, hypersonic plasma beam. This allows gettingfamiliar with main physical phenomena, dimensionless parameters, performances, parametricinvestigation, and mathematical methods to deal with a boundary problem ofa set of algebraic-differential equations.The second model adds the neutral gas population and the multiple collisional processestaking place in the discharge, and aims to reproduce the whole plasma productionstage in addition to the accelerating one. The mathematical formulation of the modelis much more complex and rigorous, and the numerical integration is challenging becauseof the presence of singular/sonic transitions at intermediate points, the presenceof terms of very different orders of magnitude, and the stiffness of boundary conditionfulfilment with respect to parametric variations. A Matlab code has been totally builtfor this model. The comparison of the two models reveals excellent similarity and validatesthe two-step method followed. Further work should deal with radial dynamicsand total energy balance considerations.
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