6 papers · 1 filter
Analysis of Moment Closures Using -Divergences for Rarefied Dynamics with Binary Collisions and Their Galerkin Discretizations
Michael R. A. Abdelmalik, Irene M. Gamba, Torsten Keßler +1
This work introduces a robust deterministic framework for approximating solutions of the Boltzmann equation with binary collisions by discretizing their dependence on time, positio…
Wigner-Eckart Factorization of the Polyatomic Boltzmann Collision Operator
Torsten Keßler, Bas W. T. Gieling, René R. Hiemstra +1
We extend the Wigner-Eckart factorization of the spectral Boltzmann collision operator to polyatomic gases with continuous internal energy. Because internal energies are invariant…
Wigner-Eckart Factorization of the Spectral Boltzmann Collision Operator
René R. Hiemstra, Torsten Keßler, Michael R. A. Abdelmalik
We reduce the eight-dimensional weak form of the bilinear Boltzmann collision operator to a five-dimensional kinematic core by rigidly rotating the laboratory frame to align with t…
Zeta expansion for long-range interactions under periodic boundary conditions with applications to micromagnetics
Andreas A. Buchheit, Jonathan K. Busse, Torsten Keßler +1
We address the efficient computation of power-law-based interaction potentials of homogeneous -dimensional bodies with an infinite -dimensional array of copies, including the…
On the computation of lattice sums without translational invariance
Andreas A. Buchheit, Torsten Keßler, Kirill Serkh
This paper introduces a new method for the efficient computation of oscillatory multidimensional lattice sums in geometries with boundaries. Such sums are ubiquitous in both pure a…
Vlasov-Poisson system tackled by particle simulation utilising boundary element methods
Torsten Keßler, Sergej Rjasanow, Steffen Weißer
This paper presents a grid-free simulation algorithm for the fully three-dimensional Vlasov--Poisson system for collisionless electron plasmas. We employ a standard particle method…