Dynamic Models for the Subgrid-Scale Mixing of Reactants in Atmospheric Turbulent Reacting Flows

Dynamic Models for Subgrid-scale Transport and Mixing of Reactants in Atmospheric Turbulent Reacting Flows

Large-eddy simulation (LES) can provide valuable highresolution spatial and temporal information required to study the effects of turbulent transport and mixing on the chemical transformation of reacting scalars in the atmospheric boundary layer (ABL). LES consists of explicitly resolving all scales of turbulent transport larger than the grid scale (on the order of tens of meters in the ABL), w...

Subgrid models in turbulent mixing

We are concerned with the chaotic flow fields of turbulent mixing. Chaotic flow is found in an extreme form in multiply shocked Richtmyer-Meshkov unstable flows. The goal of a converged simulation for this problem is to obtain converged solutions for such micro solution features as the joint probability distributions of the temperature and species concentration, as well as the macro features su...

Subgrid-scale model for the temperature fluctuations in reacting hypersonic turbulent flows

A direct numerical simulation ~DNS! database is used to develop a model of subgrid-scale temperature fluctuations for use in large-eddy simulations of turbulent, reacting hypersonic flows. The proposed model uses a probability density representation of the temperature fluctuations. The DNS database reveals a physically consistent relation between the resolved-scale flow conditions that may be u...

Subgrid Combustion Modeling for Premixed Turbulent Reacting Flows *

Two combustion models for turbulent premixed combustion in the flamelet regime are developed for unsteady simulations. The first model is a convensional G equation flamelet model and the main issues discussed are the subgrid closure. The second model is based on the Linear-Eddy Model. Both models are used in simulation of turbulent stagnation point flames. The heat release and turbulence intens...

Subgrid models for mass and thermal diffusion in turbulent mixing∗