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DOE OSTI · 3000352

Direct Discontinuous Galerkin methods for the reacting multi-component flow equations

Absillis, Gianni [North Carolina State University, Raleigh, NC (United States)] (ORCID:000000020980860X)·Luo, Hong [North Carolina State University, Raleigh, NC (United States)]·Greene, Patrick [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]·Nourgaliev, Robert [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]·Goodson, M. [Corvid Technologies, Mooresville, NC (United States)] (ORCID:0000000345706624)
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Abstract

The Direct Discontinuous Galerkin (DDG (Liu and Yan, 2008)) method and a counterpart with Interface Correction (DDGIC (Danis and Yan, 2022)) are extended to compute diffusion terms that arise when solving the compressible multi-component flow equations in thermochemical nonequilibrium. Thermodynamic properties, transport properties, chemical reaction rates, and energy exchange terms are computed using Mutation++ (Scoggins et al., 2020). The DG method is applied on unstructured grids, where the accuracy and convergence rates can be sensitive to the numerical method chosen for parabolic terms. A method for determining the homogeneity tensor of the flow equations required for DDGIC is shown. The convergence properties of the DDG methods are studied and compared to the Interior Penalty (IP) method. A number of numerical experiments are conducted to assess the accuracy and performance of the method. The numerical results and convergence studies indicate that DDG and DDGIC provide accurate solutions and perform well for general flows in thermochemical nonequilibrium.

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DiffusionDirect discontinuous GalerkinDiscontinuous GalerkinInterface correctionMulti-componentReacting

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Absillis, Gianni [North Carolina State University, Raleigh, NC (United States)] (ORCID:000000020980860X), Luo, Hong [North Carolina State University, Raleigh, NC (United States)], Greene, Patrick [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Nourgaliev, Robert [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Goodson, M. [Corvid Technologies, Mooresville, NC (United States)] (ORCID:0000000345706624). 2025-08-13. Direct Discontinuous Galerkin methods for the reacting multi-component flow equations. https://doi.org/10.1016/j.compfluid.2025.106774

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