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Related papers: Cosmological SPH simulations: The entropy equation

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We compare the statistical properties of galaxies found in two different models of hierarchical galaxy formation: the semi-analytic model of Cole et al. and the smoothed particle hydrodynamics (SPH) simulations of Pearce et al. Using a…

Astrophysics · Physics 2009-10-31 A. J. Benson , F. R. Pearce , C. S. Frenk , C. M. Baugh , A. Jenkins

We describe an SPH model for chemical enrichment and radiative cooling in cosmological simulations of structure formation. This model includes: i) the delayed gas restitution from stars by means of a probabilistic approach designed to…

(Abridged) The thermal state of the intracluster medium results from a competition between gas cooling and heating. The heating comes from two distinct sources: gravitational heating from the collapse of the dark matter halo and thermal…

Astrophysics · Physics 2009-11-13 N. L. Mitchell , I. G. McCarthy , R. G. Bower , T. Theuns , R. A. Crain

We present the smoothed-particle hydrodynamics implementation SPHGal, which combines some recently proposed improvements in GADGET. This includes a pressure-entropy formulation with a Wendland kernel, a higher order estimate of velocity…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-30 Chia-Yu Hu , Thorsten Naab , Stefanie Walch , Benjamin P. Moster , Ludwig Oser

In this paper we discuss the treatment of discontinuities in Smoothed Particle Hydrodynamics (SPH) simulations. In particular we discuss the difference between integral and differential representations of the fluid equations in an SPH…

Astrophysics · Physics 2008-11-26 Daniel J. Price

Smoothed particle hydrodynamics (SPH) employs an artificial viscosity to properly capture hydrodynamical shock waves. In its original formulation, the resulting numerical viscosity is large enough to suppress structure in the velocity field…

Astrophysics · Physics 2009-11-13 K. Dolag , F. Vazza , G. Brunetti , G. Tormen

To make relevant predictions about observable emission, hydrodynamical simulation codes must employ schemes that account for radiative losses, but the large dimensionality of accurate radiative transfer schemes is often prohibitive.…

Instrumentation and Methods for Astrophysics · Physics 2015-06-23 James C. Lombardi , William G. McInally , Joshua A. Faber

There are some traces of the existence of internal ocean in some icy moons, such as the vapor plumes of Europa and Enceladus. This implies a region of liquid water beneath the surface ice shell. Since liquid water would be essential for the…

Earth and Planetary Astrophysics · Physics 2024-10-29 Keiya Murashima , Natsuki Hosono , Takayuki R. Saitoh , Takanori Sasaki

Dealing with boundary conditions in Smoothed Particle Hydrodynamics (SPH) poses significant difficulties, indeed being one of the SPHERIC Grand Challenges. In particular, wall boundary conditions have been pivotal in SPH model development…

When modelling phase change, the latent heat released (absorbed) during solidification (melting) must be included in the heat transfer equation. In this paper, different SPH methods for the implementation of latent heat, in the context of…

Fluid Dynamics · Physics 2018-02-21 Amirsaman Farrokhpanah , Markus Bussmann , Javad Mostaghimi

Various formulations of smooth-particle hydrodynamics (SPH) have been proposed, intended to resolve certain difficulties in the treatment of fluid mixing instabilities. Most have involved changes to the algorithm which either introduce…

Instrumentation and Methods for Astrophysics · Physics 2018-06-19 Philip F. Hopkins

The smoothed-particle hydrodynamics (SPH) technique is a numerical method for solving gas-dynamical problems. It has been applied to simulate the evolution of a wide variety of astrophysical systems. The method has a second-order accuracy,…

Instrumentation and Methods for Astrophysics · Physics 2016-08-08 Domingo García-Senz , Rubén M. Cabezón , José A. Escartín , Kevin Ebinger

This paper presents an overview and introduction to Smoothed Particle Hydrodynamics and Magnetohydrodynamics in theory and in practice. Firstly, we give a basic grounding in the fundamentals of SPH, showing how the equations of motion and…

Instrumentation and Methods for Astrophysics · Physics 2010-12-22 Daniel J. Price

We present a new formulation of the equations of motion used in smoothed particle hydrodynamics (SPH). The spatial resolution in SPH is determined by the smoothing length, $h$, and it has become common practice for each particle to be given…

Astrophysics · Physics 2015-06-24 Richard P. Nelson , John C. B. Papaloizou

The method of smoothed particle hydrodynamics (SPH) is developped appropriately for the study of relativistic heavy ion collision processes. In order to describe the flow of a high energy but low baryon number density fluid, the entropy is…

High Energy Physics - Phenomenology · Physics 2008-11-26 C. E. Aguiar , T. Kodama , T. Osada , Y. Hama

In this work we will identify a novel relation between Smoothed Particle Hydrodynamics (SPH) and explicit Large Eddy Simulation (LES) using a coarse-graining method from Non-Equilibrium Molecular Dynamics (NEMD). While the current…

Fluid Dynamics · Physics 2022-11-24 Max Okraschevski , Niklas Bürkle , Rainer Koch , Hans-Jörg Bauer

Density discontinuities cannot be precisely modelled in standard formulations of smoothed particles hydrodynamics (SPH) because the density field is defined smoothly as a kernel-weighted sum of neighbouring particle masses. This is a…

We analyze the thermodynamical consistency of entropic-force cosmological models. Our analysis is based on a generalized entropy scaling with an arbitrary power of the Hubble radius. The Bekenstein-Hawking entropy, proportional to the area,…

General Relativity and Quantum Cosmology · Physics 2022-02-28 D. J. Zamora , C. Tsallis

We summarize the ideas that led to the Adaptive Smoothed Particle Hydrodynamics (ASPH) algorithm, with anisotropic smoothing and shock-tracking. We then identify a serious new problem for SPH simulations with shocks and radiative cooling…

Astrophysics · Physics 2007-05-23 Hugo Martel , Paul R. Shapiro

Smoothed particle hydrodynamics (SPH) discretization techniques are generalized to develop a method, smoothed particle interpolation (SPI), for solving initial value problems of systems of non-hydrodynamical nature. Under this approach, SPH…

Astrophysics · Physics 2009-10-22 Pablo Laguna