Zobrazeno 1 - 10
of 112
pro vyhledávání: '"Hirvijoki, Eero"'
This paper proposes a novel numerical integrator for modeling multispecies Coulomb collisions in kinetic plasmas. The proposed scheme provides an energy-, momentum-, and positivity-preserving particle discretization of the nonlinear Landau collision
Externí odkaz:
http://arxiv.org/abs/2212.00663
Plasma-terminating disruptions in future fusion reactors may result in conversion of the initial current to a relativistic runaway electron beam. Validated predictive tools are required to optimize the scenarios and mitigation actuators to avoid the
Externí odkaz:
http://arxiv.org/abs/2208.01858
This letter reports on a metriplectic formulation of collisional, nonlinear full-$f$ electromagnetic gyrokinetic theory compliant with energy conservation and monotonic entropy production. In an axisymmetric background magnetic field, the toroidal an
Externí odkaz:
http://arxiv.org/abs/2203.08464
Publikováno v:
Journal of Plasma Physics, 2021, 87(2), 905870219
Ideally, binary-collision algorithms conserve kinetic momentum and energy. In practice, the finite size of collision cells and the finite difference in the particle locations affect the conservation properties. In the present work, we investigate num
Externí odkaz:
http://arxiv.org/abs/2104.09100
Autor:
Koivunen, Tero, Hirvijoki, Eero
Publikováno v:
In Nuclear Engineering and Design February 2024 417
Autor:
Hirvijoki, Eero
Publikováno v:
Plasma Phys. Control. Fusion 63 044003 (2021)
This paper contributes new insights into discretizing Coulomb collisions in kinetic plasma models. Building on the previous works [Carrillo et al. J. Comp. Phys. X 7:100066 (2020), Hirvijoki and Burby Phys. Plasmas 27(8):082307 (2020)], I propose det
Externí odkaz:
http://arxiv.org/abs/2012.07187
Publikováno v:
Physics of Plasmas 27, 092506 (2020)
This paper investigates subcycling of particle orbits in variational, geometric particle-in-cell methods addressing the Vlasov--Maxwell system in magnetized plasmas. The purpose of subcycling is to allow different time steps for different particle sp
Externí odkaz:
http://arxiv.org/abs/2002.10759
The action principle by Low [Proc. R. Soc. Lond. A 248, 282--287] for the classic Vlasov-Maxwell system contains a mix of Eulerian and Lagrangian variables. This renders the Noether analysis of reparametrization symmetries inconvenient, especially si
Externí odkaz:
http://arxiv.org/abs/1912.06477
Autor:
Hirvijoki, Eero
This paper proposes a charge-conserving, variational, spatio-temporal discretization for the drift-kinetic Vlasov-Maxwell system, utilizing finite-elements for the electromagnetic fields and the particle-in-cell approach for the Vlasov distribution.
Externí odkaz:
http://arxiv.org/abs/1910.03441
Autor:
Varje, Jari, Särkimäki, Konsta, Kontula, Joona, Ollus, Patrik, Kurki-Suonio, Taina, Snicker, Antti, Hirvijoki, Eero, Äkäslompolo, Simppa
We present a novel implementation of a Monte Carlo particle-following code for solving the distribution function of minority species in fusion plasmas, called ASCOT5, and verify it using theoretical results for neoclassical transport. The code has be
Externí odkaz:
http://arxiv.org/abs/1908.02482