A low-Mach phase field-lattice Boltzmann-finite difference model for reactive gas flows propagating through complex shaped particle assemblies

Reza Namdar; Mohammad Norouzi; Fathollah Varnik

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arXiv · 2310.17214

A low-Mach phase field-lattice Boltzmann-finite difference model for reactive gas flows propagating through complex shaped particle assemblies

Reza Namdar·Mohammad Norouzi·Fathollah Varnik

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Abstract

The present study provides a systematic derivation of a phase-field version of the momentum, mass and heat transport equations, while accounting for chemical reactions in the fluid phase. To achieve this goal, the volume averaging technique is used to reformulate the conservation equations in the presence of multiple phases and their respective diffuse interfaces. It is shown that the structure of the multiphase/diffuse interface version of the conservation equations is very similar to the original single phase/sharp interface formulation. The multiphase character of the problem is accounted for the coupling terms, which act at the interface between adjacent phases. For the special case of a reactive fluid in contact with an inert solid, two coupling parameters are introduced, which control the exchange of momentum and heat at the interface. For numerical solver, a low-Mach number hybrid lattice Boltzmann-finite difference-phase field (LB-FD-PF) framework is developed and implemented in the open source software OpenPhase Academic. Chemical reactions of reactive flows are included into the model by coupling OpenPhase Academic with the open-source chemical kinetics software CANTERA, which delivers details of the chemical reaction mechanisms and the necessary thermodynamic and transport properties of the reacting chemical species. The model is thoroughly validated against alternative numerical simulations of reactive flows as well as experiments.

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Reza Namdar, Mohammad Norouzi, Fathollah Varnik. 2023-10-26. A low-Mach phase field-lattice Boltzmann-finite difference model for reactive gas flows propagating through complex shaped particle assemblies. https://arxiv.org/abs/2310.17214

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