English
Related papers

Related papers: CASTRO: A New Compressible Astrophysical Solver. I…

200 papers

This paper proposes a new non-oscillatory {\em energy-splitting} conservative algorithm for computing multi-fluid flows in the Eulerian framework. In comparison with existing multi-fluid algorithms in literatures, it is shown that the mass…

Fluid Dynamics · Physics 2018-04-04 Xin Lei , Jiequan Li

We develop a numerical scheme for solving a fully special relativistic resistive radiation magnetohydrodynamics. Our code guarantees conservations of total mass, momentum and energy. Radiation energy density and radiation flux are…

High Energy Astrophysical Phenomena · Physics 2019-08-19 Hiroyuki R. Takahashi , Ken Ohsuga

We have developed a method of solving for multi-species chemical reaction flows in non--equilibrium and self--consistently with the hydrodynamic equations in an expanding FLRW universe. The method is based on a backward differencing scheme…

Astrophysics · Physics 2009-10-28 Peter Anninos , Yu Zhang , Tom Abel , Michael L. Norman

A method of calculating a new class of symmetries is presented for partial differential equations. The method give a new dynamical solution for an isothermal and cylindrically symmetric hydrodynamics equations under self-gravity. The…

Exactly Solvable and Integrable Systems · Physics 2007-05-23 Souichi Murata , Kazuhiro Nozaki

We use symmetry arguments developed by Gubser to construct the first radially-expanding explicit solutions of the Israel-Stewart formulation of hydrodynamics. Along with a general semi-analytical solution, an exact analytical solution is…

Internal flows inside gravitationally stable astrophysical objects, such as the Sun, stars and compact stars are compressed and extremely subsonic. Such low Mach number flows are usually encountered when studying for example dynamo action…

Astrophysics · Physics 2007-12-24 A. Hujeirat , F. -K. Thielemann , J. Dusek , A. Nusser

Radiative transfer plays a key role in the star formation process. Due to a high computational cost, radiation-hydrodynamics simulations performed up to now have mainly been carried out in the grey approximation. In recent years,…

Instrumentation and Methods for Astrophysics · Physics 2015-05-27 Matthias González , Neil Vaytet , Benoît Commerçon , Jacques Masson

A space-time adaptive method is presented for the reactive Euler equations describing chemically reacting gas flow where a two species model is used for the chemistry. The governing equations are discretized with a finite volume method and…

Computational Physics · Physics 2019-12-16 Olivier Roussel , Kai Schneider

We propose a novel numerical method for solving multi-dimensional, special relativistic Boltzmann equations for neutrinos coupled to hydrodynamics equations. It is meant to be applied to simulations of core-collapse supernovae. We handle…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Hiroki Nagakura , Kohsuke Sumiyoshi , Shoichi Yamada

This paper presents the development of a well-balanced gas-kinetic scheme (GKS) with space-time adaptive mesh refinement (STAMR) for the shallow water equations (SWE). While well-balanced GKS have been established on Cartesian and…

Numerical Analysis · Mathematics 2025-09-03 Gaocheng Liu , Fengxiang Zhao , Jianping Gan , Kun Xu

Numerical simulations of self-gravitating flows evolve a momentum equation and an energy equation that account for accelerations and gravitational energy releases due to a time-dependent gravitational potential. In this work, we implement a…

Instrumentation and Methods for Astrophysics · Physics 2021-02-17 P. D. Mullen , Tomoyuki Hanawa , C. F. Gammie

We present a semi-Lagrangian characteristic mapping method for the incompressible Euler equations on a rotating sphere. The numerical method uses a spatio-temporal discretization of the inverse flow map generated by the Eulerian velocity as…

Numerical Analysis · Mathematics 2023-10-20 Seth Taylor , Jean-Christophe Nave

We introduce CRK-HACC, an extension of the Hardware/Hybrid Accelerated Cosmology Code (HACC), to resolve gas hydrodynamics in large-scale structure formation simulations of the universe. The new framework couples the HACC gravitational…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-01 Nicholas Frontiere , J. D. Emberson , Michael Buehlmann , Joseph Adamo , Salman Habib , Katrin Heitmann , Claude-André Faucher-Giguère

We investigate the dynamics and evolution of coalescing neutron stars. The three-dimensional Newtonian equations of hydrodynamics are integrated by the `Piecewise Parabolic Method' However, we do include the effects of the emission of…

Astrophysics · Physics 2016-08-30 M. Ruffert , H. -Th. Janka , W. Keil , G. Schaefer

We present our recently developed {\em galcon} approach to hydrodynamical cosmological simulations of galaxy clusters - a subgrid model added to the {\em Enzo} adaptive mesh refinement code - which is capable of tracking galaxies within the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Yinon Arieli , Yoel Rephaeli , Michael L. Norman

We present GRAMSES, a new pipeline for nonlinear cosmological $N$-body simulations in General Relativity (GR). This code adopts the Arnowitt-Deser-Misner (ADM) formalism of GR, with constant mean curvature and minimum distortion gauge…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-24 Cristian Barrera-Hinojosa , Baojiu Li

We present the first implementation of the Active Flux method on adaptively refined Cartesian grids. The Active Flux method is a third order accurate finite volume method for hyperbolic conservation laws, which is based on the use of point…

Numerical Analysis · Mathematics 2022-06-08 Donna Calhoun , Erik Chudzik , Christiane Helzel

Many astrophysical systems can only be accurately modelled when the behaviour of their baryonic gas components is well understood. The residual distribution (RD) family of partial differential equation (PDE) solvers produce approximate…

Instrumentation and Methods for Astrophysics · Physics 2022-12-07 Ben Morton , Sadegh Khochfar , Zhenyu Wu

The computational difficulty of six-dimensional neutrino radiation hydrodynamics has spawned a variety of approximations, provoking a long history of uncertainty in the core-collapse supernova explosion mechanism. Under the auspices of the…

In numerical models of thin astrophysical disks that use an Eulerian scheme, gas orbits supersonically through a fixed grid. As a result the time step is sharply limited by the Courant condition. Also, because the mean flow speed with…

Astrophysics · Physics 2009-11-13 Bryan M. Johnson , Xiaoyue Guan , Charles F. Gammie