6533b827fe1ef96bd1285d8b

RESEARCH PRODUCT

Minimally implicit Runge-Kutta methods for Resistive Relativistic MHD

Isabel Cordero-carriónM. A. Aloy

subject

AstrofísicaHistoryResistive touchscreenPartial differential equation010308 nuclear & particles physicsExplicit and implicit methodsNumerical methods for ordinary differential equationsStiffnessMagnetohidrodinàmica01 natural sciencesComputer Science ApplicationsEducationRunge–Kutta methods0103 physical sciencesmedicineCalculusApplied mathematicsMagnetohydrodynamic driveMagnetohydrodynamicsmedicine.symptom010303 astronomy & astrophysicsMathematics

description

The Relativistic Resistive Magnetohydrodynamic (RRMHD) equations are a hyperbolic system of partial differential equations used to describe the dynamics of relativistic magnetized fluids with a finite conductivity. Close to the ideal magnetohydrodynamic regime, the source term proportional to the conductivity becomes potentially stiff and cannot be handled with standard explicit time integration methods. We propose a new class of methods to deal with the stiffness fo the system, which we name Minimally Implicit Runge-Kutta methods. These methods avoid the development of numerical instabilities without increasing the computational costs in comparison with explicit methods, need no iterative extra loop in order to recover the primitive (physical) variables, the analytical inversion of the implicit operator is trivial and the several stages can actually be viewed as stages of explicit Runge-Kutta methods with an effective time-step. We test these methods with two different one-dimensional test beds in varied conductivity regimes, and show that our second-order schemes satisfy the theoretical expectations.

10.1088/1742-6596/719/1/012015https://doi.org/10.1088/1742-6596/719/1/012015