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Based on a geometric discretization scheme for Maxwell equations, we unveil a mathematical\textit{\}transformation between the electric field intensity $E$ and the magnetic field intensity $H$, denoted as Galerkin duality. Using Galerkin…

Computational Physics · Physics 2009-11-11 Bo He , F. L. Teixeira

The simulation of the elastodynamics equations at high-frequency suffers from the well known pollution effect. We present a Petrov--Galerkin multiscale sub-grid correction method that remains pollution free in natural resolution and…

Numerical Analysis · Mathematics 2022-03-15 Donald L. Brown , Dietmar Gallistl

Recent developments have made it possible to overcome grid-based limitations of finite difference (FD) methods by adopting the kernel-based meshless framework using radial basis functions (RBFs). Such an approach provides a meshless…

Numerical Analysis · Mathematics 2019-01-07 Pankaj K Mishra , Gregory E Fasshauer , Mrinal K Sen , Leevan Ling

Turbulence simulation codes can exploit the flute-like nature of plasma turbulence to reduce the effective number of degrees of freedom necessary to represent fluctuations. This can be achieved by employing magnetic coordinates of which one…

Plasma Physics · Physics 2015-05-18 M. A. Ottaviani

Numerical resolution of exterior Helmholtz problems requires some approach to domain truncation. As an alternative to approximate nonreflecting boundary conditions and invocation of the Dirichlet-to-Neumann map, we introduce a new, nonlocal…

Numerical Analysis · Mathematics 2021-03-04 Robert C. Kirby , Andreas Klöckner , Ben Sepanski

This paper presents a total Lagrangian mixed Petrov-Galerkin finite element formulation that provides a computationally efficient approach for analyzing Cosserat rods that is free of singularities and locking. To achieve a singularity-free…

The line-of-sight structure of the Galactic magnetic field (GMF) can be studied using Faraday rotation measure (RM) grids. We analyze how the choice of interpolation kernel can affect the accuracy and reliability of reconstructed RM maps.…

Instrumentation and Methods for Astrophysics · Physics 2024-12-24 Affan Khadir , Ayush Pandhi , Sebastian Hutschenreuter , Bryan Gaensler , Shannon Vanderwoude , Jennifer West , Shane O'Sullivan

Boundary integral equation methods for analyzing electromagnetic scattering phenomena typically suffer from several of the following problems: (i) ill-conditioning when the frequency is low; (ii) ill-conditioning when the discretization…

Computational Physics · Physics 2020-06-24 Adrien Merlini , Yves Beghein , Kristof Cools , Eric Michielssen , Francesco P. Andriulli

To design a method to solve the issues of handling 'dirty' and highly complex geometries, the topology-free method combined with the immersed boundary method is presented for viscous and incompressible flows at a high Reynolds number. The…

Computational Engineering, Finance, and Science · Computer Science 2022-06-06 Keiji Onishi , Makoto Tsubokura

In axisymmetric fusion reactors, the equilibrium magnetic configuration can be expressed in terms of the solution to a semi-linear elliptic equation known as the Grad-Shafranov equation, the solution of which determines the poloidal…

Computational Physics · Physics 2019-03-07 Tonatiuh Sánchez-Vizuet , Manuel Solano

We present a new computational method for smoothly matching general relativistic ideal magnetohydrodynamics (MHD) to its force-free limit. The method is based on a flux-conservative formalism for MHD and its force-free limit, and a vector…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Vasileios Paschalidis , Stuart L. Shapiro

Time-parallel algorithms seek greater concurrency by decomposing the temporal domain of a Partial Differential Equation (PDE), providing possibilities for accelerating the computation of its solution. While parallelisation in time has…

Numerical Analysis · Mathematics 2021-04-20 Federico Danieli , Scott MacLachlan

Numerical simulations of the propagation of charged particles through magnetic fields solving the equation of motion often leads to the usage of an interpolation in case of discretely defined magnetic fields, typically given on a…

High Energy Astrophysical Phenomena · Physics 2021-07-14 L. Schlegel , A. Frie , B. Eichmann , P. Reichherzer , J. Becker Tjus

The BOUND program calculates the bound states of a complex formed from two interacting particles using coupled-channel methods. It is particularly suitable for the bound states of atom-molecule and molecule-molecule Van der Waals complexes…

Chemical Physics · Physics 2019-03-15 Jeremy M. Hutson , C. Ruth Le Sueur

Combined plasma-coil optimization approaches for designing stellarators are discussed and a new method for calculating free-boundary equilibria is proposed. Four distinct categories of stellarator optimization, two of which are novel…

Plasma Physics · Physics 2021-05-12 Sophia A. Henneberg , Stuart R. Hudson , David Pfefferlé , Per Helander

Fourth-order differential equations play an important role in many applications in science and engineering. In this paper, we present a three-field mixed finite-element formulation for fourth-order problems, with a focus on the effective…

Numerical Analysis · Mathematics 2022-10-13 Patrick E. Farrell , Abdalaziz Hamdan , Scott P. MacLachlan

In this paper, an efficient algorithm is presented by the extrapolation technique to improve the accuracy of finite difference schemes for solving the fractional boundary value problems with non-smooth solution. Two popular finite…

Numerical Analysis · Mathematics 2016-07-26 Zhao-Peng Hao , Wan-Rong Cao

Phase-field fracture models lead to variational problems that can be written as a coupled variational equality and inequality system. Numerically, such problems can be treated with Galerkin finite elements and primal-dual active set…

Numerical Analysis · Mathematics 2020-05-04 Daniel Jodlbauer , Ulrich Langer , Thomas Wick

We investigate the competition between attractive spin-spin interactions and spin-separating external forces in the ground state of a one-dimensional Fermi-Hubbard model. We consider a lattice with open boundary conditions, subject to a…

Quantum Gases · Physics 2026-04-28 Jacek Dobrzyniecki , Thomas Busch

We use high order finite difference methods to solve the wave equation in the second order form. The spatial discretization is performed by finite difference operators satisfying a summation-by-parts property. The focus of this work is on…

Numerical Analysis · Mathematics 2017-02-08 Siyang Wang , Kristoffer Virta , Gunilla Kreiss