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A new spectral method is built resorting to $(0,2)$ Jacobi polynomials. We describe the origin and the properties of these polynomials. This choice of polynomials is motivated by their orthogonality properties with the respect to the weight…

Numerical Analysis · Mathematics 2009-10-28 Cornou Jean-Louis , Bonazzola Silvano

When simulating three-dimensional flows interacting with deformable and elastic obstacles, current methods often encounter complexities in the governing equations and challenges in numerical implementation. In this work, we introduce a…

Fluid Dynamics · Physics 2026-01-09 Andreu F. Gallen , Joan Muñoz Biosca , Mario Castro , Aurora Hernández-Machado

Frequently encountered in nature, internal solitary waves in stratified fluids are well-observed and well-studied from the experimental, the theoretical, and the numerical perspective. From the mathematical point of view, these waves are…

Analysis of PDEs · Mathematics 2014-11-03 Andreas Klaiber

A new approximation method for inverting the Poisson's equation is presented for a continuously distributed and finite-sized source in an unbound domain. The advantage of this image multipole method arises from its ability to place the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 James H. H. Chan , Tzihong Chiueh

The Degasperis-Procesi equation is an approximating model of shallow-water wave propagating mainly in one direction to the Euler equations. Such a model equation is analogous to the Camassa-Holm approximation of the two-dimensional…

Analysis of PDEs · Mathematics 2019-11-19 Ji Li , Yue Liu , Qiliang Wu

We develop and analyse finite volume methods for the Poisson problem with boundary conditions involving oblique derivatives. We design a generic framework, for finite volume discretisations of such models, in which internal fluxes are not…

Numerical Analysis · Mathematics 2019-08-12 Jerome Droniou , Matej Medla , Karol Mikula

Numerical simulation of compressible fluid flows is performed using the Euler equations. They include the scalar advection equation for the density, the vector advection equation for the velocity and a given pressure dependence on the…

Computational Engineering, Finance, and Science · Computer Science 2018-01-22 Petr N. Vabishchevich

Self similarity allows for analytic or semi-analytic solutions to many hydrodynamics problems. Most of these solutions are one dimensional. Using linear perturbation theory, expanded around such a one-dimensional solution, we find…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Re'em Sari , J. Nate Bode , Almog Yalinewich , Andrew MacFadyen

Motivated by the viewpoint of integrable systems, we study commuting flows of 2-component quasilinear equations, reducing to investigate the solutions of the wave equation with non-constant speed. In this paper, we apply the reduction…

Mathematical Physics · Physics 2023-12-15 Natale Manganaro , Alessandra Rizzo , Pierandrea Vergallo

Particle methods play an important role in computational fluid dynamics, but they are among the most difficult to implement and solve. The most common method is smoothed particle hydrodynamics, which is suitable for problem settings that…

Fluid Dynamics · Physics 2025-08-26 Masato Shibukawa , Naoya Ozaki , Maximilien Berthet

We classify all spherically symmetric spacetimes admitting a kinematic self-similar vector of the second, zeroth or infinite kind. We assume that the perfect fluid obeys either a polytropic equation of state or an equation of state of the…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Hideki Maeda , Tomohiro Harada , Hideo Iguchi , Naoya Okuyama

The stable and efficient numerical simulation of viscoelastic flows has been a constant struggle due to the High Weissenberg Number Problem. While the stability for macroscopic descriptions could be greatly enhanced by the log-conformation…

Numerical Analysis · Mathematics 2015-08-03 Philipp Knechtges

This work introduces a new higher-order accurate super compact (HOSC) finite difference scheme for solving complex unsteady three-dimensional (3D) non-Newtonian fluid flow problems. As per the author's knowledge, the proposed scheme is the…

Fluid Dynamics · Physics 2024-07-30 Ashwani Punia , Rajendra K. Ray

In this article, we study the regularity theory for two linear equations that are important in fluid dynamics: the passive scalar equation for (time-varying) shear flows close to Couette in $\mathbb T \times [-1,1]$ with vanishing…

Analysis of PDEs · Mathematics 2024-05-30 Jacob Bedrossian , Siming He , Sameer Iyer , Fei Wang

In this work, we propose a novel selective discontinuity sensor approach for numerical simulations of the compressible Navier-Stokes equations. Since transformation to characteristic space is already a common approach to reduce…

Fluid Dynamics · Physics 2023-05-16 Amareshwara Sainadh Chamarthi , Natan Hoffmann , Steven Frankel

A phase-field method for unstructured grids that is accurate, conservative, and robust is proposed in this work. The proposed method also results in bounded transport of volume fraction, and the interface thickness adapts automatically to…

Fluid Dynamics · Physics 2023-10-18 Hanul Hwang , Suhas S. Jain

We present an implicit numerical method to solve the time-dependent equations of radiation hydrodynamics (RHD) in axial symmetry assuming hydrostatic equilibrium perpendicular to the equatorial plane (1+1D) of a gaseous disk. The equations…

This paper deals with the spectral element modeling of seismic wave propagation at the global scale. Two aspects relevant to low-frequency studies are particularly emphasized. First, the method is generalized beyond the Cowling…

Geophysics · Physics 2009-11-10 Emmanuel Chaljub , Bernard Valette

Numerical solutions for the integral curves of the velocity field (streamlines), the density contours, and the accretion rate of a steady-state flow of an ideal fluid with $p=K n^\gamma$ equation of state are presented. The streamlines and…

General Relativity and Quantum Cosmology · Physics 2010-03-25 Gustavo C. Colvero , Maximiliano Ujevic

We investigate solutions of the 2d incompressible Euler equations, linearized around steady states which are radially decreasing vortices. Our main goal is to understand the smoothness of what we call the spectral density function…

Analysis of PDEs · Mathematics 2022-09-14 Alexandru D. Ionescu , Hao Jia