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相关论文: Estimating the convex relaxation of the ideal magn…

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We compute the exact relaxation and $\Lambda$-convex hull of the kinematic dynamo equations and show that they coincide. We also find the relaxation in the stationary case.

偏微分方程分析 · 数学 2023-01-18 Lauri Hitruhin , Sauli Lindberg

The gap between a recently developed dynamical version of relaxed magnetohydrodynamics (RxMHD) and ideal MHD (IMHD) is bridged by approximating the zero-resistivity "Ideal" Ohm's Law (IOL) constraint using an augmented Lagrangian method…

等离子体物理 · 物理学 2022-02-23 R. L. Dewar , Z. S. Qu

We describe a magnetohydrodynamic (MHD) constrained energy functional for equilibrium calculations that combines the topological constraints of ideal MHD with elements of Taylor relaxation. Extremizing states allow for partially chaotic…

等离子体物理 · 物理学 2012-04-03 S. R. Hudson , R. L. Dewar , M. J. Hole , M. McGann

We consider the three-dimensional incompressible free-boundary magnetohydrodynamics (MHD) equations in a bounded domain with surface tension on the boundary. We establish a priori estimate for solutions in the Lagrangian coordinates with…

偏微分方程分析 · 数学 2021-04-30 Chenyun Luo , Junyan Zhang

We propose and analyze a new method for the unsteady incompressible magnetohydrodynamics equations on convex domains with hybrid approximations of both vector-valued and scalar-valued fields. The proposed method is convection-semirobust,…

数值分析 · 数学 2026-02-11 Daniele A. Di Pietro , Jerome Droniou , Vito Patierno

In this note we consider the ideal compressible magneto-hydrodynamics (MHD) equations in a special two dimensional setting. We show that there exist particular initial data for which one obtains infinitely many entropy-conserving weak…

偏微分方程分析 · 数学 2021-02-04 Christian Klingenberg , Simon Markfelder

Using relativistic, steady, axisymmetric, ideal magnetohydrodynamics (MHD) we analyze the super-Alfvenic regime of a pulsar wind by means of solving the momentum equation along the flow as well as in the transfield direction. Employing a…

天体物理学 · 物理学 2009-11-10 Nektarios Vlahakis

Metriplectic dynamics is applied to compute equilibria of fluid dynamical systems. The result is a relaxation method in which Hamiltonian dynamics (symplectic structure) is combined with dissipative mechanisms (metric structure) that…

等离子体物理 · 物理学 2018-12-05 C. Bressan , M. Kraus , P. J. Morrison , O. Maj

This article serves as a summary outlining the mathematical entropy analysis of the ideal magnetohydrodynamic (MHD) equations. We select the ideal MHD equations as they are particularly useful for mathematically modeling a wide variety of…

数值分析 · 数学 2017-08-14 Dominik Derigs , Gregor J. Gassner , Stefanie Walch , Andrew R. Winters

Many astrophysical processes involving magnetic fields and quasi-stationary processes are well described when assuming the fluid as a perfect conductor. For these systems, the ideal-magnetohydrodynamics (MHD) description captures the…

天体物理学 · 物理学 2010-11-09 Carlos Palenzuela , Luis Lehner , Oscar Reula , Luciano Rezzolla

Ideal magnetohydrodynamics (IMHD) is strongly constrained by an infinite number of microscopic constraints expressing mass, entropy and magnetic flux conservation in each infinitesimal fluid element, the latter preventing magnetic…

等离子体物理 · 物理学 2015-12-02 Robert L. Dewar , Zensho Yoshida , Amitava Bhattacharjee , Stuart R. Hudson

We revisit the issue of conservation of magnetic helicity and the Woltjer-Taylor relaxation theory in magnetohydrodynamics in the context of weak solutions. We introduce a relaxed system for the ideal MHD system, which decouples the effects…

偏微分方程分析 · 数学 2021-09-21 Daniel Faraco , Sauli Lindberg , László Székelyhidi

We study and develop constraint preserving boundary conditions for the Newtonian magnetohydrodynamic equations and analyze the behavior of the numerical solution upon considering different possible options.

天体物理学 · 物理学 2009-06-23 Mariana Cecere , Luis Lehner , Oscar Reula

Newcomb's Lagrangian for ideal magnetohydrodynamics (MHD) in Lagrangian labeling is discretized using discrete exterior calculus. Variational integrators for ideal MHD are derived thereafter. Besides being symplectic and…

等离子体物理 · 物理学 2014-10-27 Yao Zhou , Hong Qin , J. W. Burby , A. Bhattacharjee

We show that ideal 2D MHD does not possess weak solutions (or even subsolutions) with compact support in time and non-trivial magnetic field. We also show that the $\Lambda$-convex hull of ideal MHD has empty interior in both 2D and 3D;…

偏微分方程分析 · 数学 2018-01-23 Daniel Faraco , Sauli Lindberg

In this paper, we investigate the similarity solutions for a steady laminar incompressible boundary layer equations governing the Magnetohydrodynamic (MHD) flow near the forward stagnation point of two-dimensional and axisymmetric bodies.…

经典物理 · 物理学 2007-05-23 Jean-David Hoernel

This article describes a method to compute successive convex approximations of the convex hull of a set of points in R^n that are the solutions to a system of polynomial equations over the reals. The method relies on sums of squares of…

最优化与控制 · 数学 2010-07-27 João Gouveia , Rekha R. Thomas

Compressible ideal magnetohydrodynamics (MHD) is formulated in terms of the time evolution of potential vorticity and magnetic flux per unit mass using a compact Lie bracket notation. It is demonstrated that this simplifies analytic…

等离子体物理 · 物理学 2014-02-03 Wayne Arter

We discuss a manifestly covariant formulation of ideal relativistic magnetohydrodynamics, which has been recently used in astrophysical and heavy-ion contexts, and compare it to other similar frameworks. We show that the covariant equations…

核理论 · 物理学 2018-11-14 Wojciech Florkowski , Avdhesh Kumar , Radoslaw Ryblewski

The low Mach number limit for the multi-dimensional full magnetohydrodynamic equations, in which the effect of thermal conduction is taken into account, is rigorously justified in the framework of classical solutions with small density and…

偏微分方程分析 · 数学 2015-05-28 Song Jiang , Qiangchang Ju , Fucai Li
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