English
Related papers

Related papers: Eigenvalue Method for NEI Unit in FLASH Code

200 papers

A flux-splitting method is proposed for the hyperbolic-equation system (HES) of magnetized electron fluids in quasi-neutral plasmas. The numerical fluxes are split into four categories, which are computed by using an upwind method which…

Computational Physics · Physics 2017-12-11 R. Kawashima , K. Komurasaki , T. Schoenherr

In this work, we implement a relatively new analytical technique, the Improved Amplitude-Frequency Formulation (IAFF) method, approach for solving accurate approximate analytical solutions for strong nonlinear oscillators, which may contain…

Dynamical Systems · Mathematics 2021-10-05 R. Azami , D. D. Ganji , A. G. Davodi , H. Babazadeh

A very simple and accurate numerical method which is applicable to systems of differentio-integral equations with quite general boundary conditions has been devised. Although the basic idea of this method stems from the Keller Box method,…

Fluid Dynamics · Physics 2014-09-30 Jian-Jun Shu , Graham Wilks

We develop a new algorithm to estimate the temperature of a nonneutral plasma in a Penning-Malmberg trap. The algorithm analyzes data obtained by slowly lowering a voltage that confines one end of the plasma and collecting escaping charges,…

Plasma Physics · Physics 2024-09-19 Adrianne Zhong , Joel Fajans , Jonathan S. Wurtele

A new scheme for incorporating radiative cooling in hydrodynamical codes is presented, centered around exact integration of the governing semi-discrete cooling equation. Using benchmark calculations based on the cooling downstream of a…

Solar and Stellar Astrophysics · Physics 2009-11-13 R. H. D. Townsend

This paper presents a novel and efficient approach for the computation of energy eigenvalues in quantum semiconductor heterostructures. Accurate determination of the electronic states in these heterostructures is crucial for understanding…

Mesoscale and Nanoscale Physics · Physics 2024-06-18 J. D. Phan , A. -V. Phan

Low-lying shell model states may be approximated accurately by a sum over products of proton and neutron states. The optimal factors are determined by a variational principle and result from the solution of rather low-dimensional eigenvalue…

Nuclear Theory · Physics 2007-05-23 T. Papenbrock , A. Juodagalvis , D. J. Dean

It is economical to devise ways and means to simplify a multi-species particle system. The single fluid MHD description of a plasma is sufficiently adequate to study plasma phenomena . A plasma containing multi-species of particles can also…

Plasma Physics · Physics 2021-06-16 V. Krishan

This work focuses on the development of a self adjusting multirate strategy based on an implicit time discretization for the numerical solution of hyperbolic equations, that could benefit from different time steps in different areas of the…

Numerical Analysis · Mathematics 2018-02-14 Ludovica Delpopolo Carciopolo , Luca Bonaventura , Anna Scotti , Luca Formaggia

We discuss the application of Widom insertion method for calculation of the chemical potential of individual ions in computer simulations with Ewald summation. Two approaches are considered. In the first approach, an individual ion is…

Soft Condensed Matter · Physics 2022-03-21 Amin Bakhshandeh , Yan Levin

Ion transport, often described by the Poisson--Nernst--Planck (PNP) equations, is ubiquitous in electrochemical devices and many biological processes of significance. In this work, we develop conservative, positivity-preserving, energy…

Numerical Analysis · Mathematics 2020-07-15 Jie Ding , Zhongming Wang , Shenggao Zhou

Solvation free energy is an important quantity in Computational Chemistry with a variety of applications, especially in drug discovery and design. The accurate prediction of solvation free energies of small molecules in water is still a…

Biological Physics · Physics 2007-05-23 A. Hildebrandt , O. Kohlbacher , R. Blossey , H. -P. Lenhof

A hybrid spectral/finite-element code is developed to numerically solve the resistive finite-pressure magnetohydrodynamic equilibria without the necessity of postulating nested magnetic flux surfaces in the non-axisymmetric toroidal…

Plasma Physics · Physics 2024-12-30 Jian Zhang , Ping Zhu , Chris C. Hegna

In [1], the non-linear space-time Hasegawa-Mima plasma equation is formulated as a coupled system of two linear PDE's, a solution of which is a pair (u, w). The first equation is of hyperbolic type and the second of elliptic type.…

Numerical Analysis · Mathematics 2022-02-04 Sophie M. Moufawad , Nabil R. Nassif

This paper presents a novel framework for tensor eigenvalue analysis in the context of multi-modal data fusion, leveraging topological invariants such as Betti numbers. Traditional approaches to tensor eigenvalue analysis often extend…

Machine Learning · Statistics 2025-05-29 Ronald Katende

We present a novel approach to accelerate iterative methods to solve nonlinear Schr\"odinger eigenvalue problems using neural networks. Nonlinear eigenvector problems are fundamental in quantum mechanics and other fields, yet conventional…

Numerical Analysis · Mathematics 2025-07-23 Daniel Peterseim , Jan-F. Pietschmann , Jonas Püschel , Kilian Ruess

Quasi-dynamic energy flow calculation is an indispensable tool for the heat and electricity integrated energy system (HE-IES) analysis. One solves the nonlinear partial differential algebraic equations to obtain thermal, hydraulic and…

Systems and Control · Electrical Eng. & Systems 2022-09-27 Ruizhi Yu , Wei Gu

We present a theoretical framework to describe state-resolved ionization dynamics of neon atoms driven by ultraintense x-ray free-electron-laser pulses. In general, x-ray multiphoton ionization dynamics of atoms have been described by…

Atomic Physics · Physics 2023-01-10 Laura Budewig , Sang-Kil Son , Robin Santra

In the standard "monoenergetic" approach to numerical calculation of stellarator neoclassical transport, to expedite computation, ad-hoc changes are made to the kinetic equation so speed enters only as a parameter. Here we examine the…

Plasma Physics · Physics 2015-05-27 Matt Landreman

We perform nonadiabatic simulations of warm dense aluminum based on the electron-force field (EFF) variant of wave-packet molecular dynamics. Comparison of the static ion-ion structure factor with density functional theory (DFT) is used to…

Plasma Physics · Physics 2020-12-08 Ryan A. Davis , W. A. Angermeier , R. Hermsmeier , Thomas G. White