RT Conference Proceedings
T1 Collisional effects in non-stationary plasma expansions along convergent-divergent magnetic nozzles
A1 Zhou, Jiewei
A1 Sánchez Arriaga, Gonzalo
A1 Ahedo Galilea, Eduardo Antonio
A1 Martinez-Sánchez, M.
A1 Ramos, Jesús José
AB The electron-electron collisional effect on the nonstationary expansion of a plasma in a convergentdivergent magnetic nozzle is studied. Under paraxial and fully magnetized plasmas approximations, an Eulerian code has been adapted to solve Poisson's equation coupled with the kinetic transport equations for plasma species, i.e. a Vlasov equation for singly-charged ions and a Boltzmann equation with a Bhatnagar-Gross-Kook operator for electrons. The study is focused on weakly collisional plasma plumes, which have a collisional time scale larger than the transit time in the nozzle of typical electrons. A kinetic analysis shows that phasespace regions of isolated, doubly-trapped electrons that are nearly empty in the collisionless case are progressively populated due to the electron-electron collisions. Such a higher density of trapped electrons modifies the profile of the electrostatic potential, which keeps almost unaltered the density of free electrons and decreases the density of the reflected ones. As compared with the collisionless case, the collisions decrease the length of the downstream sheath and the parallel electron temperature while increasing the normal one. Therefore the steady plasma state is more isotropic. The simulations show that collisions erase the time history of the system and, unlike the collisionless case, the steady state is unique.
YR 2018
FD 2018-05
LK https://hdl.handle.net/10016/27853
UL https://hdl.handle.net/10016/27853
LA eng
NO Proceeding of: Space Propulsion Conference, SP 2018,14-18 mayo, Sevilla
NO J.Z. was supported by Airbus DS (Grant CW240050). G.S-A was supported by the Ministerio de Economíıa y Competitividad of Spain (Grant RYC-2014-15357). E.A. was supported by the MINOTOR project, that received funding from the European Union’s Horizon2020 research and innovation programme,under grant agreement 730028. J.R. and M.M-S stays at UC3M for this research were supported by a UC3M-SantanderChairof Excellence and by National R&D Plan (Grant ESP2016-75887), respectively.
DS e-Archivo
RD 18 jul. 2024