Survey of Turbulent Combustion Models for Large-Eddy Simulations of Propulsive Flowfields

摘要: A general review of turbulent combustion modeling closures applicable to large eddy simulations (LES) is provided. The focus on “regime-independent” models able provide ranging from purely premixed non-premixed and all regimes between these two limits. Special emphasis placed primary propulsion applications, including liquid rocket engines, diesel gas turbines, scramjets. These applications span a range physical phenomena both idealand real-gas behavior, single-phase multi-phase combustion, relatively low Mach number supersonic hypersonic simple geometries highly complex geometries. Three classes are identified as possibly providing such broad based closures: flamelet-library/presumed probability density function (PDF) models, linear (LEM), transported PDF or filtered (FDF) models. This focuses fundamental assumptions that apply across the each individually. Namely, regarding presumed size dimensional scalar manifold models; however, flamelet almost always presume only few dimensions necessary yield adequate representation larger, manifold. In contrast, LEM FDF not, in theory, bound by any (i.e. direct calculation possible); due current computational limitations, often employ reduction techniques which usually not restrictive those used Individual associated with specific formulation model also analyzed. From discussions, additional novel results testing some provided unique database DNS high pressure reacting temporally developing shear flames. includes H2/O2, H2/Air, Kerosene/Air flames detailed reduced chemistry. include real property equation state, generalized heat mass diffusion derived non-equilibrium thermodynamics. Reynolds numbers pressures (up 125 atm), resolutions approaching 1 billion grid points. Finally, comments towards future challenges related LES offered.