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A discontinuous Galerkin method for the discretization of the compressible Euler equations, the governing equations of inviscid fluid dynamics, on Cartesian meshes is developed for use of Graphical Processing Units via OCCA, a unified…

Computational Physics · Physics 2020-09-01 Andrew C. Kirby , Dimitri J. Mavriplis

We present the numerical methods and GPU-accelerated implementation underlying a Total Lagrangian finite element framework for finite-deformation flexible multibody dynamics, introduced in the companion paper [1]. The framework supports…

Computational Engineering, Finance, and Science · Computer Science 2026-05-04 Zhenhao Zhou , Ruochun Zhang , Ganesh Arivoli , Dan Negrut

Our work is motivated by the analysis of ash plume dynamics, arising in the study of volcanic eruptions. Such phenomena are characterized by large Reynolds number (exceeding $10^7$) and a large number of polydispersed particles~[1]. Thus,…

The numerical solution of the Kadanoff-Baym nonlinear integro-differential equations, which yields the non-equilibrium Green's functions (NEGFs) of quantum many-body systems, poses significant computational challenges due to its high…

Distributed, Parallel, and Cluster Computing · Computer Science 2025-05-27 Jia Yin , Khaled Z. Ibrahim , Mauro Del Ben , Jack Deslippe , Yang-hao Chan , Chao Yang

An essential ingredient of a spectral method is the choice of suitable bases for test and trial spaces. On complex domains, these bases are harder to devise, necessitating the use of domain partitioning techniques such as the spectral…

Numerical Analysis · Mathematics 2021-11-17 Saad Qadeer , Ehssan Nazockdast , Boyce E. Griffith

We present an improved method for computing incompressible viscous flow around suspended rigid particles using a fixed and uniform computational grid. The main idea is to incorporate Peskin's regularized delta function approach [Acta…

Fluid Dynamics · Physics 2018-09-24 Markus Uhlmann

We present a method for solving the two-dimensional linearized collisionless Boltzmann equation using Fourier expansion along the orbits. It resembles very much solutions present in the literature, but it differs by the fact that everything…

Astrophysics · Physics 2007-05-23 P. Vauterin , H. Dejonghe

Particle acceleration in collisionless plasma systems is a central question in astroplasma and astroparticle physics. The structure of the acceleration regions, electron-ion energy equilibration, preacceleration of particles at shocks to…

High Energy Astrophysical Phenomena · Physics 2020-02-19 Martin Pohl , Masahiro Hoshino , Jacek Niemiec

abridged] A method to rapidly estimate the Fourier power spectrum of a point distribution is presented. This method relies on a Taylor expansion of the trigonometric functions. It yields the Fourier modes from a number of FFTs, which is…

Astrophysics · Physics 2009-11-13 Stephane Colombi , Andrew H. Jaffe , Dmitri Novikov , Christophe Pichon

The present study addresses the challenge of enhancing computational efficiency without compromising accuracy in numerical simulations of vacuum gas dynamics using the direct simulation Monte Carlo (DSMC) method. A technique termed "fixed…

Fluid Dynamics · Physics 2024-07-03 Moslem Sabouri , Ramin Zakeri , Amin Ebrahimi

The Monte Carlo method is a powerful technique for computing thermodynamic magnetic states of otherwise unsolvable spin Hamiltonians, but the method becomes computationally prohibitive with increasing number of spins and the simulation of…

Computational Physics · Physics 2021-06-22 Michalis Charilaou

I compare various popular and unpopular techniques for simulating large collisionless stellar systems. I give a quantitative comparison of the raw cpu times required for five separate codes, including tree codes and basis function…

Astrophysics · Physics 2008-02-03 J A Sellwood

Recent increases in supercomputing power, driven by the multi-core revolution and accelerators such as the IBM Cell processor, graphics processing units (GPUs) and Intel's Many Integrated Core (MIC) technology have enabled kinetic…

In these notes we construct the momentum-space potentials from configuration-space using for the Fourier-transformation the Gaussian-Expansion-Method (GEM). This has the advantage that the Fourier-Bessel integrals can be performed…

Nuclear Theory · Physics 2014-09-22 Th. A. Rijken

An implementation of the fast multiple method (FMM) is performed for magnetic systems with long-ranged dipolar interactions. Expansion in spherical harmonics of the original FMM is replaced by expansion of polynomials in Cartesian…

Computational Physics · Physics 2015-05-13 Wen Zhang , Stephan Haas

This paper presents a "two-dimensional Fourier Continuation" method (2D-FC) for construction of bi-periodic extensions of smooth non-periodic functions defined over general two-dimensional smooth domains. The approach can be directly…

Numerical Analysis · Mathematics 2020-10-19 Oscar P. Bruno , Jagabandhu Paul

A Gaussian process (GP)-based methodology is proposed to emulate complex dynamical computer models (or simulators). The method relies on emulating the numerical flow map of the system over an initial (short) time step, where the flow map is…

Methodology · Statistics 2024-11-26 Hossein Mohammadi , Peter Challenor , Marc Goodfellow

The study of alloys using computational methods has been a difficult task due to the usually unknown stoichiometry and local atomic ordering of the different structures experimentally. In order to combat this, first-principles methods have…

Materials Science · Physics 2021-12-08 Daniel Wines , Kayahan Saritas , Can Ataca

The design of microfluidic devices is a cumbersome and tedious process that can be significantly improved by simulation. Methods based on Computational Fluid Dynamics (CFD) are considered state-of-the-art, but require extensive compute time…

Computational Engineering, Finance, and Science · Computer Science 2024-01-17 Michel Takken , Robert Wille

We present a computational framework for piecewise constant functions (PCFs) and use this for several types of computations that are useful in statistics, e.g., averages, similarity matrices, and so on. We give a linear-time,…

Computation · Statistics 2024-04-11 Björn H. Wehlin