Numerical treatment of turbulent reacting flows

Many practical devices involving flows with chemical reactions operate in the turbulent flow regime. This is easily understood considering the fact that the chemical species must be put in contact at the molecular level for the reactions to proceed, a process which is intensified significantly by turbulent transport. In this chapter, we first discuss the modifications to the Navier–Stokes equations needed to model multicomponent reacting flows. Then, the models for both transport phenomena and chemical sources required to close the system are discussed. After that, the numerical treatments specialized for reactive variable density and fully compressible flows are addressed, including boundary conditions. Numerical strategies for solving large and stiff chemical systems and for automatically reducing them for simulation of complex flows are reviewed, and finally, the calibration of mesh resolution and adaptive mesh methods are presented.