Compressible Flamelet Model with Thickened Flame Closure in an All-Speed Combustion Solver

摘要

A robust unsteady turbulent compressible combustion modeling capability developed in a CFD solver called Loci-STREAM is presented in this paper. It utilizes the flamelet methodology extended to account for compressibility involving both ideal and real fluids. The ideal-gas thermodynamics is modeled by linearizing the specific heat ratio whereas the parameters needed for the cubic Peng Robinson equation of state are pre-tabulated for the evaluation of departure functions and a quadratic expression is used to model the attraction parameter. This compressible model is able to account for temperature and pressure variations from the baseline flamelet table. This solver integrates proven numerical methods for generalized grids and state-of-the-art physical models in a rule-based programming framework called Loci which allows: (a) seamless integration of multidisciplinary physics in a unified manner, and (b) automatic handling of parallel computing. The objective is to be able to routinely simulate unsteady combustion in complex geometries such as liquid rocket engines requiring large unstructured grids and complex multidisciplinary physics.