24 citations · 33 across the 17 of their papers we have counts for
18 papers
An Efficient Solver for Finite Element-based Constrained Transport in 3D Magnetohydrodynamics Applied to Magnetic Confinement Fusion
Golo A. Wimmer, Konstantin Lipnikov, Ben S. Southworth +1
We present an efficient solver framework for the stiff magnetic wave coupling arising in resistive magnetohydrodynamics (MHD) on realistic tokamak geometries. The approach builds o…
Broken-space Additive Schwarz Mass Inverse Approximations and (Block) Preconditioning
Oliver A. Krzysik, Ben S. Southworth, Golo A. Wimmer
Finite-element mass matrix solves and approximate inverses arise often in explicit time integration as well as Schur-complement-based block preconditioning. A diagonal approximatio…
A black-box, multilevel algebraic preconditioning framework for conforming finite elements
O. A. Krzysik, B. S. Southworth, G. A. Wimmer
Recently we introduced the least-squares algebraic-multigrid domain-decomposition (LS-AMG-DD) method as a multilevel, algebraic preconditioner for sparse symmetric positive definit…
An Agentic Orchestration of Atomistic Simulations
Rahul Somasundaram, Adela Habib, Khanh Dang +12
Atomistic simulations are central to materials design, but their execution involves complex, multi-step workflows that require significant human expertise. Here, we present an agen…
A Physics-Informed Neural Network for Solving the Quasi-static Magnetohydrodynamic Equations
Jonathan S. Arnaud, Christopher J. McDevitt, Golo Wimmer +1
A physics-informed neural network (PINN) is developed, for the first time, to learn the time-dependent quasi-static magnetohydrodynamic (MHD) equations in axisymmetric tokamak geom…
Structure-Preserving Transfer of Grad-Shafranov Equilibria to Magnetohydrodynamic Solvers
Rushan Zhang, Golo Wimmer, Qi Tang
Magnetohydrodynamic (MHD) solvers used to study dynamic plasmas for magnetic confinement fusion typically rely on initial conditions that describe force balance, which are provided…
Optimal transfer operators in algebraic two-level methods for nonsymmetric and indefinite problems
Oliver A. Krzysik, Ben S. Southworth, Golo A. Wimmer +3
Consider an algebraic two-level method applied to the -dimensional linear system using fine-space preconditioner (i.e., ``relaxation'' or ``smoother'…
High order interpolation of magnetic fields with vector potential reconstruction for particle simulations
Oleksii Beznosov, Jesus Bonilla, Xianzhu Tang +1
We propose a method for interpolating divergence-free continuous magnetic fields via vector potential reconstruction using Hermite interpolation, which ensures high-order continuit…
An accurate SUPG-stabilized continuous Galerkin discretization for anisotropic heat flux in magnetic confinement fusion
Golo A. Wimmer, Ben S. Southworth, Koki Sagiyama +1
We present a novel spatial discretization for the anisotropic heat conduction equation, aimed at improved accuracy at the high levels of anisotropy seen in a magnetized plasma, for…
Multiscale approximation and two-grid preconditioner for extremely anisotropic heat flow
Maria Vasilyeva, Golo A. Wimmer, Ben S. Southworth
We consider anisotropic heat flow with extreme anisotropy, as arises in magnetized plasmas for fusion applications. Such problems pose significant challenges in both obtaining an a…
A structure-preserving discontinuous Galerkin scheme for the Cahn-Hilliard equation including time adaptivity
Golo A. Wimmer, Ben S. Southworth, Qi Tang
We present a novel spatial discretization for the Cahn-Hilliard equation including transport. The method is given by a mixed discretization for the two elliptic operators, with the…
A fast algebraic multigrid solver and accurate discretization for highly anisotropic heat flux I: open field lines
Golo A. Wimmer, Ben S. Southworth, Thomas J. Gregory +1
We present a novel solver technique for the anisotropic heat flux equation, aimed at the high level of anisotropy seen in magnetic confinement fusion plasmas. Such problems pose tw…
Structure preserving transport stabilized compatible finite element methods for magnetohydrodynamics
Golo A. Wimmer, Xianzhu Tang
We present compatible finite element space discretizations for the ideal compressible magnetohydrodynamic equations. The magnetic field is considered both in div- and curl-conformi…
Improving the accuracy of discretisations of the vector transport equation on the lowest-order quadrilateral Raviart-Thomas finite elements
Thomas M Bendall, Golo A Wimmer
Within finite element models of fluids, vector-valued fields such as velocity or momentum variables are commonly discretised using the Raviart-Thomas elements. However, when using…
Computational modeling for high-fidelity coarsening of shallow water equations based on subgrid data
Sagy Ephrati, Erwin Luesink, Golo Wimmer +2
Small-scale features of shallow water flow obtained from direct numerical simulation (DNS) with two different computational codes for the shallow water equations are gathered offli…
Bioluminescence modeling for deep sea experiments
Stephan Meighen-Berger, Li Ruohan, Golo Wimmer
We develop a modeling framework for bioluminescence light found in the deep sea near neutrino telescopes by combining a hydrodynamic model with a stochastic one. The bioluminescenc…
Energy conserving SUPG methods for compatible finite element schemes in numerical weather prediction
Golo A. Wimmer, Colin J. Cotter, Werner Bauer
We present an energy conserving space discretisation based on a Poisson bracket that can be used to derive the dry compressible Euler as well as thermal shallow water equations. It…
Energy conserving upwinded compatible finite element schemes for the rotating shallow water equations
Golo Wimmer, Colin Cotter, Werner Bauer
We present an energy conserving space discretisation of the rotating shallow water equations using compatible finite elements. It is based on an energy and enstrophy conserving Ham…