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arXiv · 1909.08044

Influence of toroidal flow on stationary density of collisionless plasmas

Elias Laribi·Shun Ogawa·Guilhem Dif-Pradalier·Alexei Vasiliev·Xavier Garbet·Xavier Leoncini
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Abstract

Starting from the given passive particle equilibrium particle cylindrical profiles, we built self-consistent stationary conditions of the Maxwell-Vlasov equation at thermodynamic equilibrium with non-flat density profiles. The solutions to the obtained equations are then discussed. It appears that the presence of an azimuthal (poloidal) flow in the plasma can insure radial confinement, while the presence of a longitudinal (toroidal) flow can enhance greatly the confinement. Moreover in the global physically reasonable situation, we find that no unstable point can emerge in the effective integrable Hamiltonian of the individual particles, hinting at some stability of the confinement when considering a toroidal geometry in the large aspect ratio limit.

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Elias Laribi, Shun Ogawa, Guilhem Dif-Pradalier, Alexei Vasiliev, Xavier Garbet, Xavier Leoncini. 2019-09-17. Influence of toroidal flow on stationary density of collisionless plasmas. https://doi.org/10.3390/fluids4030172

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