Burnett-level multi-relaxation-time central-moment discrete Boltzmann modeling of reactive flows

Qingbin Wu; Chuandong Lin; Huilin Lai

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arXiv · 2507.03877

Burnett-level multi-relaxation-time central-moment discrete Boltzmann modeling of reactive flows

Qingbin Wu·Chuandong Lin·Huilin Lai

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Abstract

A multi-relaxation-time central-moment discrete Boltzmann method (CDBM) is developed for compressible reactive flows, incorporating the effects of chemical reactions. The Chapman--Enskog multiscale analysis demonstrates that the model recovers the Burnett equations in the hydrodynamic limit, with tunable specific heat ratios and Prandtl numbers. Within the CDBM framework, a unified Boltzmann equation governs the evolution of hydrodynamic variables, thermodynamic quantities, and higher-order central moments. The collision and reaction term are consistently computed via matrix inversion method. A two-dimensional twenty-five discrete velocities, exhibiting favorable spatial symmetry, is constructed and employed. The model is validated through simulations of the thermal Couette flow, homogeneous chemical reaction, steady detonation wave, and collision of two detonation waves. This work presents a versatile numerical simulation tool capable of addressing complex reactive flows characterized by hydrodynamic and thermodynamic nonequilibrium effects, applicable to both scientific research and engineering practice.

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Qingbin Wu, Chuandong Lin, Huilin Lai. 2025-07-05. Burnett-level multi-relaxation-time central-moment discrete Boltzmann modeling of reactive flows. https://arxiv.org/abs/2507.03877

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