English
Related papers

Related papers: Adaptive Mesh Refinement and Relativistic MHD

200 papers

This work presents the first numerical investigation of using Voigt regularization as a method for obtaining magnetohydrodynamic (MHD) equilibria without the assumption of nested magnetic flux surfaces. Voigt regularization modifies the MHD…

Plasma Physics · Physics 2025-06-16 Yi-Min Huang , Justin Kin Jun Hew , Andrew Brown , Amitava Bhattacharjee

We describe a photon-conserving radiative transfer algorithm, using a spatially-adaptive ray tracing scheme, and its parallel implementation into the adaptive mesh refinement (AMR) cosmological hydrodynamics code, Enzo. By coupling the…

Instrumentation and Methods for Astrophysics · Physics 2015-05-20 John H. Wise , Tom Abel

A new algorithm for solving the general relativistic MHD equations is described in this paper. We design our scheme to incorporate black hole excision with smooth boundaries, and to simplify solving the combined Einstein and MHD equations…

General Relativity and Quantum Cosmology · Physics 2009-11-11 David Neilsen , Eric W Hirschmann , R Steven Millward

We consider within a finite element approach the usage of different adaptively refined meshes for different variables in systems of nonlinear, time-depended PDEs. To resolve different solution behaviours of these variables, the meshes can…

Numerical Analysis · Mathematics 2010-05-27 Thomas Witkowski , Axel Voigt

We introduce an $r-$adaptive algorithm to solve Partial Differential Equations using a Deep Neural Network. The proposed method restricts to tensor product meshes and optimizes the boundary node locations in one dimension, from which we…

Numerical Analysis · Mathematics 2022-10-21 Ángel J. Omella , David Pardo

Efforts to achieve better accuracy in numerical relativity have so far focused either on implementing second order accurate adaptive mesh refinement or on defining higher order accurate differences and update schemes. Here, we argue for the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Luis Lehner , Steven L. Liebling , Oscar Reula

The magnetohydrodynamics (MHD) equations are generally known to be difficult to solve numerically, due to their highly nonlinear structure and the strong coupling between the electromagnetic and hydrodynamic variables, especially for high…

Numerical Analysis · Mathematics 2022-11-22 Fabian Laakmann

We derive a number of solution for one-dimensional dynamics of relativistic magnetized plasma that can be used as benchmark estimates in relativistic hydrodynamic and magnetohydrodynamic numerical codes. First, we analyze the properties of…

High Energy Astrophysical Phenomena · Physics 2015-06-03 Maxim Lyutikov , Samuel Hadden

We present a finite-volume, genuinely 4th-order accurate numerical method for solving the equations of resistive relativistic magnetohydrodynamics (Res-RMHD) in Cartesian coordinates. In our formulation, the magnetic field is evolved in…

High Energy Astrophysical Phenomena · Physics 2024-07-12 Andrea Mignone , Vittoria Berta , Marco Rossazza , Matteo Bugli , Giancarlo Mattia , Luca Del Zanna , Lorenzo Pareschi

This article investigates residual a posteriori error estimates and adaptive mesh refinements for time-dependent boundary element methods for the wave equation. We obtain reliable estimates for Dirichlet and acoustic boundary conditions…

Numerical Analysis · Mathematics 2020-10-01 Heiko Gimperlein , Ceyhun Oezdemir , David Stark , Ernst P. Stephan

The convergence of an adaptive mixed finite element method for general second order linear elliptic problems defined on simply connected bounded polygonal domains is analyzed in this paper. The main difficulties in the analysis are posed by…

Numerical Analysis · Mathematics 2014-02-14 Asha K. Dond , Neela Nataraj , Amiya K. Pani

State of the art models of the ISM use adaptive mesh refinement to capture small scale structures, by refining on the fly those regions of the grid where density and pressure gradients occur, keeping at the same time the existing resolution…

Astrophysics · Physics 2007-05-23 M. A. de Avillez , Dieter Breitschwerdt

We present the design and implementation details of a geometric multigrid method on adaptively refined meshes for massively parallel computations. The method uses local smoothing on the refined part of the mesh. Partitioning is achieved by…

Numerical Analysis · Computer Science 2021-08-04 Thomas C. Clevenger , Timo Heister , Guido Kanschat , Martin Kronbichler

Computational studies that use block-structured adaptive mesh refinement (AMR) approaches suffer from unnecessarily high mesh resolution in regions adjacent to important solution features. This deficiency limits the performance of AMR…

Computational Physics · Physics 2022-03-02 Brandon Gusto , Tomasz Plewa

We consider the iterative reconstruction of both the internal geometry and the values of an inhomogeneous acoustic refraction index through a piecewise constant approximation. In this context, we propose two enhancements intended to reduce…

Numerical Analysis · Mathematics 2015-06-15 Yann Grisel , Jean-Pierre Raymond , Pierre-Alain Mazet , Vincent Mouysset

The capability of the adaptive optics to correct for the segmentation error is analyzed in terms of the residual wavefront RMS and the power spectral density of the phase. The analytical model and the end-to-end simulation give…

Astrophysics · Physics 2009-11-11 Natalia Yaitskova , Christophe Verinaud

Solving the problem of fast eruptive events in magnetically dominated astrophysical plasmas requires the use of particularly well adapted numerical tools. Indeed, the central mechanism based on magnetic reconnection is determined by a…

High Energy Astrophysical Phenomena · Physics 2019-08-07 Hubert Baty

Stochastic models of chemical systems are often analysed by solving the corresponding Fokker-Planck equation which is a drift-diffusion partial differential equation for the probability distribution function. Efficient numerical solution of…

Numerical Analysis · Mathematics 2011-11-10 Simon L. Cotter , Tomas Vejchodsky , Radek Erban

We formulate hydrodynamic equations for nonsuperfluid multicomponent magnetized charged relativistic mixtures, taking into account chemical reactions as well as viscosity, diffusion, thermodiffusion, and thermal conductivity effects. The…

High Energy Astrophysical Phenomena · Physics 2020-06-18 Vasiliy A. Dommes , Mikhail E. Gusakov , Peter S. Shternin

We study a regularised version of the magnetohydrodynamics (MHD) equations, the tamed MHD (TMHD) equations. They are a model for the flow of electrically conducting fluids through porous media. We prove existence and uniqueness of TMHD on…

Analysis of PDEs · Mathematics 2020-03-16 Andre Schenke