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Related papers: An Explicit Scheme for Incorporating Ambipolar Dif…

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Within the context of a viscoresistive magnetohydrodynamic (MHD) model with anisotropic heat transport and cross-field mass diffusion, we introduce novel three-term representations for the magnetic field (background vacuum field, field line…

Plasma Physics · Physics 2019-10-15 Nikita Nikulsin , Matthias Hoelzl , Alessandro Zocco , Karl Lackner , Sibylle Günter

Magneto-hydrodynamics is one of the foremost models in plasma physics with applications in inertial confinement fusion, astrophysics and elsewhere. Advanced numerical methods are needed to get an insight into the complex physical phenomena.…

Computational Physics · Physics 2022-03-29 Jan Nikl , Milan Kuchařík , Stefan Weber

The aim of the present work is to derive rigorous estimates for turbulent MHD flow quantities such as the size and anisotropy of the dissipative scales, as well as the transition between 2D and 3D state. To this end, we calculate an upper…

Fluid Dynamics · Physics 2020-06-11 Alban Pothérat , Thierry Alboussière

We present a novel combination of numerical techniques to improve the efficiency, accuracy, and robustness of multi-component compressible flow simulations. At the core of our approach is an Entropy-Stable formulation that preserves kinetic…

Computational Engineering, Finance, and Science · Computer Science 2025-06-17 Vahid Badrkhani , T. Jeremy P. Karpowsk , Christian Hasse

We propose a novel finite-difference time-domain (FDTD) scheme for the solution of the Maxwell's equations in which linear dispersive effects are present. The method uses high-order accurate approximations in space and time for the…

Numerical Analysis · Mathematics 2017-06-15 Michael J. Jenkinson , Jeffrey W. Banks

We employ simulations of supersonic super-Alfvenic turbulence decay as a benchmark test problem to assess and compare the performance of nine astrophysical MHD methods actively used to model star formation. The set of nine codes includes:…

In this work we introduce a novel semi-implicit structure-preserving finite-volume/finite-difference scheme for the viscous and resistive equations of magnetohydrodynamics (MHD) based on an appropriate 3-split of the governing PDE system,…

Numerical Analysis · Mathematics 2021-12-01 Francesco Fambri

We study propagating Alfven waves by solving the time-dependent equations of magnetohydrodynamics (MHD) in one dimension numerically. In a homogeneous medium the circularly polarized Alfven wave is an exact solution of the ideal MHD…

Astrophysics · Physics 2007-05-23 R. Turkmani , U. Torkelsson

The generation of turbulence at magnetized shocks and its subsequent interaction with the latter is a key question of plasma- and high-energy astrophysics. This paper presents two-dimensional magnetohydrodynamic simulations of a fast shock…

High Energy Astrophysical Phenomena · Physics 2018-01-09 Camilia Demidem , Martin Lemoine , Fabien Casse

Kinetic equations model distributions of particles in position-velocity phase space. Often, one is interested in studying the long-time behavior of particles in high-collisional regimes in which an approximate (advection)-diffusion model…

Numerical Analysis · Mathematics 2021-07-09 Emil Løvbak , Giovanni Samaey , Stefan Vandewalle

Under ideal MHD conditions the magnetic field strength should be correlated with density in the interstellar medium (ISM). However, observations indicate that this correlation is weak. Ambipolar diffusion can decrease the flux-to-mass ratio…

Astrophysics · Physics 2009-11-10 F. Heitsch , E. G. Zweibel , A. D. Slyz , J. E. G. Devriendt

We present a novel artificial diffusion method to circumvent the instabilities associated with the standard finite element approximation of convection-diffusion equations. Motivated by the micromorphic approach, we introduce an auxiliary…

Numerical Analysis · Mathematics 2025-06-19 Soheil Firooz , B. Daya Reddy , Paul Steinmann

This paper presents a spatial two-grid (STG) compact difference scheme for a two-dimensional (2D) nonlinear diffusion-wave equation with variable exponent, which describes, e.g., the propagation of mechanical diffusive waves in viscoelastic…

Numerical Analysis · Mathematics 2025-10-15 Hao Zhang , Kexin Li , Wenlin Qiu

The ideal Magnetohydrodynamics (MHD) equations are challenging because one needs to maintain the divergence free condition, $\nabla \cdot \Bv = 0$. Many numerical methods have been developed to enforce this condition. In this work, we…

Numerical Analysis · Mathematics 2019-08-06 Firat Cakir , Andrew Christlieb , Yan Jiang

In this paper, we investigate the use of a mass lumped fully explicit time stepping scheme for the discretisation of the wave equation with underlying material parameters that vary at arbitrarily fine scales. We combine the leapfrog scheme…

Numerical Analysis · Mathematics 2021-09-08 Sjoerd Geevers , Roland Maier

A hyperbolic system approach is proposed for robust computation of anisotropic diffusion equations that appear in quasineutral plasmas. Though the approach exhibits merits of high extensibility and accurate flux computation, the…

Numerical Analysis · Mathematics 2025-09-12 Tokuhiro Eto , Rei Kawashima

Nonlinear diffusion equations of spectral transfer are systematically derived for anisotropic magnetohydrodynamics in the regime of wave turbulence. The background of the analysis is the asymptotic Alfv\'en wave turbulence equations from…

Solar and Stellar Astrophysics · Physics 2015-05-19 Sebastien Galtier , Eric Buchlin

Nonthermal acceleration of particles in magnetohydrodynamic (MHD) turbulence plays a central role in a wide variety of astrophysical sites. This physics is addressed here in the context of a strong turbulence, composed of coherent…

High Energy Astrophysical Phenomena · Physics 2021-10-06 Martin Lemoine

We consider a two-dimensional MHD model describing the evolution of viscous, compressible and electrically conducting fluids under the action of vertical magnetic field without resistivity. Existence of global weak solutions is established…

Analysis of PDEs · Mathematics 2019-07-02 Yang Li , Yongzhong Sun

We have derived the full set of MHD equations for incompressible shear flow of a magnetized fluid and considered their solution in the wave-vector space. The linearized equations give the famous amplification of slow magnetosonic waves and…

Plasma Physics · Physics 2015-05-27 Z. D. Dimitrov , Y. G. Maneva , T. S. Hristov , T. M. Mishonov