Electric Thruster Plume Simulation: Application to Mpd and Feep Thrusters

This paper describes the physical and numerical models of the two new codes which are under developing phase at Alta. 2d3vPICFES is bi-dimensional axial-symmetric numerical code able to compute plasma flow in a MPD thrusters with applied magnetic field, while 3dBEMPIC is a three dimensional numerical code able to compute the ion plume of FEEP thrusters. 2d3vPICFES uses a Particle-In-Cell technique only for positive charged particles while a continuous Fluid-Dynamics approach is used for electron simulation. The Flux Vector Splitting scheme, which captures discontinuity phenomena such as shock waves and rarefaction, is applied to solve electrons conservation equations. The ion dynamics module and the electron fluid-dynamics one are separately tested in order to verify the right functioning of the adopted numerical schemes for assigned initial and boundary conditions. 3dBEMPIC is based on a Particle-In-Cell simulation technique for both ions and electrons. The solution of Poisson’s equation is achieved by a hybrid method resulting from the joining of the Boundary Element Method and the iterative Multigrid scheme. Additional computational routines are implemented to address the phenomena related to the formation and evolution of charge-exchange ions. Nomenclature Br,z = radial and axial magnetic induction B = vector of magnetic induction B0 = magneto static field vector Bp = induced magnetic field vector Er,z = radial and axial electric field E = electric field vector I = current I = unit tensor Je = electron current density vector je = electron scalar current k = Boltzmann constant mi,e = ion and electron mass ni,e = ion and electron number density n = surface normal vector * Project Manager, Industrial Services, [email protected]. † Aerospace Engineer, MSc, Industrial Services, [email protected].. ‡ Associate Professor, University of Pisa, AIAA senior member, [email protected]. § Chief Executive Officer, [email protected]. ** Aerospace Engineer, Industrial Services, [email protected].