![Sample our Engineering & Technology journals, sign in here to start your access, latest two full volumes FREE to you for 14 days]({"type":"image" , "src" : "/sda/5933/TOC-Subject-Sample-2021-Engineering-Tech.jpg"})
Abstract
The modeling of transport in premixed turbulent flames is considered. In this context of second order modeling of momentum and scalar turbulent fluxes, special attention is paid to the closure of pressure fluctuating terms responsible for counter-gradient diffusion and flame generated turbulence effects. Based on a relatively general form of the PDF made of a series of delta functions, a new modeling proposal for these terms is introduced. The resulting model for the pressure terms takes into account (i) a nonreactive part that represents density changes, (ii) a reactive part directly related to mean chemical rate and (iii) an isotropization part which is a generalisation of the “return-to-isotropy” model for constant density flows. The model is tested using a three-dimensional compressible Direct Numerical Simulation database of a statistically steady planar turbulent premixed flame. A good agreement is found between the model expressions and the pressure fluctuating terms evaluated from DNS.
The authors wish to thank CNRS and EDF group for financial supports and C. Losier (LCD, ENSMA) for technical assistance.
