On the Formulation of the Governing Equations of Combustion systems
Christer Fureby, Edvin Lundgren, Sven-Inge Möller · 2024
Numerical simulation of combustion processes has become an important tool in theoretical studies of combustion and has also been useful in engineering problems for combustion related applications in industry. This presentation will focus on the formulation of the physical model, which constitute the basic theoretical framework in simulation models, especially in numerical simulations of combustion processes. A general physical model for simulation of gaseous material flows can be derived from general theories of mixtures based on the methods and principles of modem continuum mechanics. A brief discussion of the theory of mixtures within modem continuum physics will be presented and a general set of governing equations for a diffusive and reactive mixture will be given. Also the constitutive relations describing the material properties will be discussed. The general governing equations derived will be compared with the corresponding equations in traditional combustion models The conventional Fick’s law for mass diffusion, usually used in combustion simulations, will be compared with a general relation for the mass diffusion vectors that can be given, also a multi-temperature mixture model will be discussed.