THEORETICAL VALIDATION OF THE SOM COMBUSTION MODEL USING DNS OF TURBULENT REACTING FLOWS

摘要

The direct numerical simulation of incompressible turbulent reacting channel flows was carried out using a spectral method. The instantaneous results show the turbulence structure and the near-wall strip structures of concentration and temperature fluctuations. The DNS statistical results give the budget of the terms in the scalar correlation equations, showing that the production and dissipation terms are most important. The DNS statistical data are used to validate the closure models in the second-order moment (SOM) combustion models in RANS modeling. It is found that the simulated values of diffusion and production terms are in agreement with the DNS data in most flow regions, except in the near-wall region, where the near-wall modification should be made, and the closure model for the dissipation term needs further improvement. The algebraic second-order moment (ASOM) combustion model is well validated by DNS.