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Related papers: Helioseismic Modeling of Background Flows

200 papers

We consider the efficient numerical solution of the three-dimensional wave equation with Neumann boundary conditions via time-domain boundary integral equations. A space-time Galerkin method with $C^\infty$-smooth, compactly supported basis…

Numerical Analysis · Mathematics 2015-03-26 A. Veit , M. Merta , J. Zapletal , D. Lukáš

We discuss current advances in forward and inverse modeling for local helioseismology. We report theoretical uniqueness results, in particular the Novikov-Agaltsov reconstruction algorithm, which is relevant to solving the non-linear…

Solar and Stellar Astrophysics · Physics 2017-07-28 Laurent Gizon , Damien Fournier , Thorsten Hohage

A finite element based computational scheme is developed and employed to assess a duality based variational approach to the solution of the linear heat and transport PDE in one space dimension and time, and the nonlinear system of ODEs of…

Numerical Analysis · Mathematics 2023-10-10 Uditnarayan Kouskiya , Amit Acharya

Numerical simulations of compressible real-fluid flows are notoriously plagued by spurious pressure oscillations arising in regions of abrupt flow variations. As a possible remedy, several numerical formulations enforce the pressure…

Fluid Dynamics · Physics 2026-05-27 Gennaro Coppola , Alessandro Aiello , Carlo De Michele

Non-stationary Euler flows of gases are studied. The system of differential equations describing such flows can be represented by means of 2-forms on zero-jet space and we get some exact solutions by means of such a representation.…

Mathematical Physics · Physics 2020-04-13 Valentin Lychagin , Mikhail Roop

In this paper, we describe a new hydrodynamics code for 1D and 2D astrophysical simulations, BETHE-hydro, that uses time-dependent, arbitrary, unstructured grids. The core of the hydrodynamics algorithm is an arbitrary Lagrangian-Eulerian…

Astrophysics · Physics 2009-11-13 Jeremiah W. Murphy , Adam Burrows

This paper presents DENSER, an efficient and effective approach leveraging 3D Gaussian splatting (3DGS) for the reconstruction of dynamic urban environments. While several methods for photorealistic scene representations, both implicitly…

Computer Vision and Pattern Recognition · Computer Science 2024-09-17 Mahmud A. Mohamad , Gamal Elghazaly , Arthur Hubert , Raphael Frank

We present an accurate and efficient solver for atmospheric dynamics simulations that allows for non-conforming mesh refinement. The model equations are the conservative Euler equations for compressible flows. The numerical method is based…

Numerical Analysis · Mathematics 2023-05-18 Giuseppe Orlando , Tommaso Benacchio , Luca Bonaventura

Turbulence in compressible plasma plays a key role in many areas of astrophysics and engineering. The extreme plasma parameters in these environments, e.g. high Reynolds numbers, supersonic and super-Alfvenic flows, however, make direct…

In this paper, we propose energy-conserving Eulerian solvers for the two-species Vlasov-Amp\`{e}re (VA) system and apply the methods to simulate current-driven ion-acoustic instability. The algorithm is generalized from our previous work…

Numerical Analysis · Mathematics 2015-06-19 Yingda Cheng , Andrew J. Christlieb , Xinghui Zhong

It has been demonstrated that the Euler equations of inviscid fluid are incomplete: according to the principle of release of constraints, absence of shear stresses must be compensated by additional degrees of freedom, and leads to…

Fluid Dynamics · Physics 2012-08-31 Michail Zak

We prove that small smooth irrotational but charged perturbations of a constant background are global and go back to equilibrium in the 3D electron Euler-Poissson equation.

Analysis of PDEs · Mathematics 2012-04-09 Pierre Germain , Nader Masmoudi , Benoit Pausader

The Euler-Poincar\'e approach to complex fluids is used to derive multiscale equations for computationally modelling Euler flows as a basis for modelling turbulence. The model is based on a \emph{kinematic sweeping ansatz} (KSA) which…

Fluid Dynamics · Physics 2015-06-04 Darryl D. Holm , Cesare Tronci

In passive imaging, one attempts to reconstruct some coefficients in a wave equation from correlations of observed randomly excited solutions to this wave equation. Many methods proposed for this class of inverse problem so far are only…

Numerical Analysis · Mathematics 2024-03-12 Björn Müller , Thorsten Hohage , Damien Fournier , Laurent Gizon

We present a Monte Carlo simulation for the response of the Laser Interferometer Space Antenna (LISA) to the galactic gravitational wave background. The simulated data streams are used to estimate the number and type of binary systems that…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Seth E. Timpano , Louis J. Rubbo , Neil J. Cornish

In this paper, we develop a high order structure-preserving local discontinuous Galerkin (DG) scheme for the compressible self-gravitating Euler equations, which pose great challenges due to the presence of time-dependent gravitational…

Numerical Analysis · Mathematics 2025-10-07 Liang Pan , Wei Chen , Jianxian Qiu , Tao Xiong

A vertical slice model is developed for the Euler-Boussinesq equations with a constant temperature gradient in the direction normal to the slice (the Eady-Boussinesq model). The model is a solution of the full three-dimensional equations…

Numerical Analysis · Mathematics 2017-11-27 Hiroe Yamazaki , Jemma Shipton , Michael J. P. Cullen , Lawrence Mitchell , Colin J. Cotter

We consider three-dimensional inviscid irrotational flow in a two layer fluid under the effects of gravity and surface tension, where the upper fluid is bounded above by a rigid lid and the lower fluid is bounded below by a flat bottom. We…

Analysis of PDEs · Mathematics 2019-07-24 Dag Nilsson

In present article we consider the problems of concentrated point force which is moving with constant velocity and oscillating with cyclic frequency in unbounded homogeneous anisotropic elastic two-dimensional medium. The properties of…

Mathematical Physics · Physics 2009-11-10 G. Iovane , A. V. Nasedkin , M. Ciarletta

We present a simulation for the interactions of shockwaves with light spherical density inhomogeneities. Euler equations for two-phase compressible flows are solved in a 3D uniform resolution finite volume based solver using 5th order WENO…

Fluid Dynamics · Physics 2015-06-11 Babak Hejazialhosseini , Diego Rossinelli , Petros Koumoutsakos