COMBUSTION SCIENCE & ENGINEERING, INC. — Department of Defense STTR Phase I: Computational Fluid Dynamics (CFD) solvers based on RANS, URANS or LES are required to est

Description

Computational Fluid Dynamics (CFD) solvers based on RANS, URANS or LES are required to estimate the filtered reaction rates to account for the turbulent-chemistry interactions for accurate modeling of reactive flows. It is critical to have a reliable reaction rate estimation scheme coupled with turbulent combustion models to estimate filtered reaction rates computationally efficient way. In this work, Combustion Science & Engineering (CSE), Inc. proposes to develop a new technically innovative time-scale based"adaptive chemistry scheme"coupled with off-line Linear Eddy Mixing (LEM) model to evaluate filtered reaction rates for RANS/URANS/LES simulation. This dynamic reduced kinetic modeling approach will reduce the computational cost of chemical source term estimation significantly by reducing the number of species to be evaluated locally as well as reducing the stiffness of the ODEs to be solved. The goal here is to develop a robust and dynamically evolving kinetics model that will be combined with the mixing model of LEM to account for the effect of small time scales of relevance to supersonic combustion. Competition between mixing and molecular processes will also be included to assess the importance of the latter on turbulent-chemistry interaction.