10 papers
Perspectives on Sustainable Computational Science and Engineering
Julia Kowalski, Ann S. Almgren, Achim Basermann +43
Computational Science and Engineering (CSE) combines expertise at the intersection of engineering, applied mathematics, and computer science to form powerful methods for model-base…
Sparse entropic quadrature for moment equations
Georgii Oblapenko, Michael Herty, Manuel Torrilhon
In the present work, we study the properties of the sparse entropic quadrature method, a recently proposed method for the closure of systems of moment equations in rarefied gas dyn…
Sparse and low-rank kinetic distribution estimation
Georgii Oblapenko, Lambert Theisen, Rostislav-Paul Wilhelm +2
In this paper, we consider methods that allow for memory-efficient storage of high-dimensional distributions and retain certain key features thereof, specifically in a kinetic theo…
Moment-preserving particle merging via non-negative least squares
Georgii Oblapenko, Manuel Torrilhon
A novel particle merging algorithm for rarefied gas dynamics simulations is proposed that can conserve arbitrary velocity and spatial moments of the particle distribution via solvi…
Sparse Reconstruction of Multi-Dimensional Kinetic Distributions
Georgii Oblapenko, Manuel Torrilhon, Michael Herty
In the present work, we propose a novel method for reconstruction of multi-dimensional kinetic distributions, based on their representation as a mixture of Dirac delta functions. T…
Modeling of Chemical Reactions in Rarefied Gas Flows by the Kinetic Fokker-Planck Method
Leo Basov, Georgii Oblapenko, Martin Grabe
We propose a novel approach for modeling chemical reactions within the particle-based Fokker-Planck framework for gas flow simulations which conserves mass, momentum, and energy wh…
A Non-Negative Least Squares-based Approach for Moment-Preserving Particle Merging
Georgii Oblapenko
In the present work, a novel particle merging scheme is proposed for PIC-DSMC simulations, based on the solution of a Non-negative Least Squares problem. The merging algorithm cons…
Entropy-stable fluxes for high-order Discontinuous Galerkin simulations of high-enthalpy flows
Georgii Oblapenko, Arseniy Tarnovskiy, Moritz Ertl +1
In the present work, we extend the Discontinuous Galerkin Spectral Element Method (DGSEM) to high-enthalpy reacting gas flows with internal degrees of freedom. An entropy- and kine…
On Nonlinear Closures for Moment Equations Based on Orthogonal Polynomials
Eda Yilmaz, Georgii Oblapenko, Manuel Torrilhon
In the present work, an approach to the moment closure problem on the basis of orthogonal polynomials derived from Gram matrices is proposed. Its properties are studied in the cont…
Entropy-conservative high-order methods for high-enthalpy gas flows
Georgii Oblapenko, Manuel Torrilhon
A framework for numerical evaluation of entropy-conservative volume fluxes in gas flows with internal energies is developed, for use with high-order discretization methods. The nov…