English
Related papers

Related papers: Collisionless Stellar Hydrodynamics as an Efficien…

200 papers

We present and test a general-purpose code, called PPASPH, for evolving self-gravitating fluids in astrophysics, both with and without a collisionless component. In PPASPH, hydrodynamical properties are computed by using the SPH (Smoothed…

Astrophysics · Physics 2009-10-28 Arturo Serna , Jean-Michel Alimi , Jean-Pierre Chieze

We propose a new numerical procedure to simulate a single dark halo of any size and mass in a hierarchical framework coupling the extended Press-Schechter formalism (EPSF) to N-body simulations. The procedure consists of assigning…

Astrophysics · Physics 2009-11-07 Elena D'Onghia , Claudio Firmani , Guido Chincarini

Computational fluid dynamics is a crucial tool to theoretically explore the cosmos. In the last decade, we have seen a substantial methodological diversification with a number of cross-fertilizations between originally different methods.…

Instrumentation and Methods for Astrophysics · Physics 2023-01-25 Stephan Rosswog

First, a meshless simulation method is presented for multiphase fluid-particle flows with a two-way coupled Smoothed Particle Hydrodynamics (SPH) for the fluid and the Discrete Element Method (DEM) for the solid phase. The unresolved fluid…

Fluid Dynamics · Physics 2014-02-28 Martin Robinson , Stefan Luding , Marco Ramaioli

We introduce the cosmological HYPER code based on an innovative hydro-particle-mesh (HPM) algorithm for efficient and rapid simulations of gas and dark matter. For the HPM algorithm, we update the approach of Gnedin & Hui (1998) to expand…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-09 Yizhou He , Hy Trac , Nickolay Y. Gnedin

In this book chapter we describe the {\em Lagrangian} numerical relativity code \sphi. This code evolves spacetimes in full General Relativity by integrating the BSSN equations on structured meshes with a simple dynamical mesh refinement…

General Relativity and Quantum Cosmology · Physics 2024-05-22 S. Rosswog , P. Diener

We compare two state-of-the-art numerical codes to study the overall accuracy in modeling the intergalactic medium and reproducing Lyman-$\alpha$ forest observables for DESI and high-resolution data sets. The codes employ different…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-30 Solène Chabanier , J. D. Emberson , Zarija Lukić , Jesus Pulido , Salman Habib , Esteban Rangel , Jean Sexton , Nicholas Frontiere , Michael Buehlmann

Modified Newtonian dynamics (MOND) is a promising alternative to dark matter. To further test the theory, there is a need for fluid- and particle-dynamics simulations. The force in MOND is not a direct particle-particle interaction, but…

Astrophysics of Galaxies · Physics 2023-12-06 P. M. Visser , S. W. H. Eijt , J. V. de Nijs

In this paper we describe an adaptive softening length formalism for collisionless N-body and self-gravitating Smoothed Particle Hydrodynamics (SPH) calculations which conserves momentum and energy exactly. This means that spatially…

Astrophysics · Physics 2016-08-31 D. J. Price , J. J. Monaghan

We present a new radiative transfer method (SPH-M1RT) that is coupled dynamically with smoothed particle hydrodynamics (SPH). We implement it in the (task-based parallel) SWIFT galaxy simulation code but it can be straightforwardly…

Instrumentation and Methods for Astrophysics · Physics 2021-07-06 T. K. Chan , Tom Theuns , Richard Bower , Carlos Frenk

We present the newly-incorporated gray radiation hydrodynamics capabilities of the FLASH code based on a radiation flux-limiter aware hydrodynamics numerical implementation designed specifically for applications in astrophysical problems.…

Solar and Stellar Astrophysics · Physics 2019-08-27 Emmanouil Chatzopoulos , Klaus Weide

In this paper, we present a multi-resolution smoothed particle hydrodynamics (SPH) method for modeling fluid-structure interaction (FSI) problems. By introducing different smoothing lengths and time steps, the spatio-temporal discretization…

Computational Engineering, Finance, and Science · Computer Science 2019-12-02 Chi Zhang , Massoud Rezavand , Xiangyu Hu

We present and test a code for two-fluid simulations of galaxy formation, one of the fluids being collision-less. The hydrodynamical evolution is solved through the SPH method while gravitational forces are calculated using a tree method.…

Astrophysics · Physics 2007-05-23 John Hultman , Daniel Kaellander

We present a method for integrating the cosmological hydrodynamical equations including a collisionless dark matter component. For modelling the baryonic matter component, we use the Piecewise Parabolic Method (PPM) which is a high-accuracy…

Astrophysics · Physics 2007-05-23 A. Sornborger , B. Fryxell , K. Olson , P. MacNeice

We present two new Lagrangian methods for hydrodynamics, in a systematic comparison with moving-mesh, SPH, and stationary (non-moving) grid methods. The new methods are designed to simultaneously capture advantages of both smoothed-particle…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-15 Philip F. Hopkins

Within a cosmological context, we study the behaviour of collisionless particles in the weak field approximation to General Relativity, allowing for large gradients of the fields and relativistic velocities for the particles. We consider a…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-03 Julian Adamek , Mateja Gosenca , Shaun Hotchkiss

We describe the implementation and testing of a smoothed particle hydrodynamics (SPH) code that solves the equations of radiation hydrodynamics in the flux-limited diffusion (FLD) approximation. The SPH equations of radiation hydrodynamics…

Astrophysics · Physics 2009-11-10 Stuart C. Whitehouse , Matthew R. Bate

We test and improve the numerical schemes in our smoothed particle hydrodynamics (SPH) code for cosmological simulations, including the pressure-entropy formulation (PESPH), a time-dependent artificial viscosity, a refined timestep…

The smoothed particle hydrodynamics (SPH) technique is a purely Lagrangian method, used in numerical simulations of fluids in astrophysics and computational fluid dynamics, among many other fields. SPH simulations with detailed physics…

Galaxy mergers have been investigated for decades using smoothed particle hydrodynamics (SPH), but recent work highlighting inaccuracies inherent in the traditional SPH technique calls into question the reliability of previous studies. We…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-26 Christopher C. Hayward , Paul Torrey , Volker Springel , Lars Hernquist , Mark Vogelsberger