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In this paper, the second in a series, we document the algorithms and solvers for compressible nonrelativistic hydrodynamics implemented in GenASiS (General Astrophysical Simulation System)---a new code being developed initially and…

Instrumentation and Methods for Astrophysics · Physics 2015-07-09 Christian Y. Cardall , Reuben D. Budiardja , Eirik Endeve , Anthony Mezzacappa

We have developed a new massively-parallel radiation-hydrodynamics code (Cosmos) for Newtonian and relativistic astrophysical problems that also includes radiative cooling, self-gravity, and non-equilibrium, multi-species chemistry. Several…

Astrophysics · Physics 2009-11-07 Peter Anninos , P. Chris Fragile , Stephen D. Murray

We propose an extension to recently developed Relativistic Lattice Boltzmann solvers (RLBM), which allows the simulation of flows close to the free streaming limit. Following previous works [Phys. Rev. C 98 (2018) 035201], we use product…

A measurement of the neutrino mass scale will be achieved with cosmological probes in the upcoming decade. On one hand, the inclusion of massive neutrinos in the linear perturbation theory of cosmological structure formation is well…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-26 Caio Nascimento

Kinetic or Boltzmann schemes are interesting alternatives to the macroscopic numerical methods for solving the hyperbolic conservation laws of gas dynamics. They utilize the particle-based description instead of the wave propagation models.…

Computational Physics · Physics 2016-12-26 N. Venkata Raghavendra , S. V. Raghurama Rao

We generalize to three dimensions (3D) a recently developed improved multi-component pseudopotential lattice Boltzmann method and analyze its applicability to simulate flows through realistic porous media. The model is validated and…

Fluid Dynamics · Physics 2022-10-04 M. Sedahmed , R. C. V. Coelho , N. A. M. Araújo , E. M. Wahba , H. A. Warda

Running large-scale computer codes for huge fluid flow problems requires not only large supercomputers but also efficient and well-optimized computer codes that save the resources of those supercomputers. This paper evaluates the…

Computational Physics · Physics 2024-08-02 Maja Bacza , Tadeusz Tomczak , Maciej Matyka

We propose a numerical methodology for the numerical simulation of distinct, interacting physical processes described by a combination of compressible, inert and reactive forms of the Euler equations, multiphase equations and elastoplastic…

Computational Physics · Physics 2018-05-09 Louisa Michael , Nikolaos Nikiforakis

We describe an axisymmetric general relativistic code for rotational core collapse. The code evolves the coupled system of metric and fluid equations using the ADM 3+1 formalism and a conformally flat metric approximation of the Einstein…

Astrophysics · Physics 2009-11-07 Harald Dimmelmeier , Jose A. Font , Ewald Mueller

In the physically non viscous fluid dynamics, "shock capturing" methods adopt either an artificial viscosity contribution or an appropriate Riemann solver algorithm. These techniques are necessary to solve the strictly hyperbolic Euler…

Fluid Dynamics · Physics 2010-06-22 G. Lanzafame

A new N-body and hydrodynamical code, called RAMSES, is presented. It has been designed to study structure formation in the universe with high spatial resolution. The code is based on Adaptive Mesh Refinement (AMR) technique, with a tree…

Astrophysics · Physics 2014-10-13 Romain Teyssier

This study enhances the application of Physics-Informed Neural Networks (PINNs) for modeling discontinuous solutions in both hydrodynamics and relativistic hydrodynamics. Conventional PINNs, trained with partial differential equation…

Fluid Dynamics · Physics 2025-09-15 Jorge F. Urbán , José A. Pons

We develop a new Riemannian descent algorithm that relies on momentum to improve over existing first-order methods for geodesically convex optimization. In contrast, accelerated convergence rates proved in prior work have only been shown to…

Optimization and Control · Mathematics 2021-02-16 Foivos Alimisis , Antonio Orvieto , Gary Bécigneul , Aurelien Lucchi

We describe a new, faster implicit algorithm for solving the radiation hydrodynamics equations in the flux-limited diffusion approximation for smoothed particle hydrodynamics. This improves on the method elucidated in Whitehouse & Bate by…

Astrophysics · Physics 2009-11-13 Stuart C. Whitehouse , Matthew R. Bate , Joe J. Monaghan

To simulate the dynamics of fluid with polydisperse particles on macroscale level, one has to solve hydrodynamic equations with several relaxation terms, representing momentum transfer from fluid to particles and vice versa. For small…

Radiative transfer plays a major role in high-energy astrophysics. In multiple scenarios and in a broad range of energy scales, the coupling between matter and radiation is essential to understand the interplay between theory, observations…

High Energy Astrophysical Phenomena · Physics 2022-12-28 Jose López-Miralles , Jose María Martí , Manel Perucho

In this paper we revise two classical examples of Relativistic Hydrodynamics in order to illustrate in detail the numerical methods commonly used in fluid dynamics, specifically those designed to deal with shocks, which are based on a…

General Relativity and Quantum Cosmology · Physics 2012-12-07 F. S. Guzman , F. D. Lora-Clavijo , M. D. Morales

Methods to solve the relativistic hydrodynamic equations are a key computational kernel in a large number of astrophysics simulations and are crucial to understanding the electromagnetic signals that originate from the merger of…

Instrumentation and Methods for Astrophysics · Physics 2015-12-02 Jackson DeBuhr , Bo Zhang , Matthew Anderson , David Neilsen , Eric W. Hirschmann

A recently obtained set of the equations for leading-order (3+1)D anisotropic hydrodynamics is tested against exact solutions of the Boltzmann equation with the collisional kernel treated in the relaxation time approximation. In order to…

High Energy Physics - Phenomenology · Physics 2016-01-20 Leonardo Tinti , Radoslaw Ryblewski , Wojciech Florkowski , Michael Strickland

Particle methods play an important role in the study of a wide variety of astrophysical fluid dynamics problems. The different methods currently in use are all variants of the so-called Smoothed Particle Hydrodynamics (SPH) scheme…

Astrophysics · Physics 2009-10-31 Frederic A. Rasio