Transported probability density function modeling of a bluff body stabilized turbulent flame

摘要

A transported probability density function (PDF) approach closed at the joint scalar level is used to model the bluff body stabilized turbulent diffusion flame (HM1) investigated experimentally by Masri and co-workers (Re = 15,800). The current effort extends previous work through the introduction of comprehensive thermochemistry computed via a systematically reduced C/H/N/O mechanism featuring 300 reactions, 20 solved, and 28 steady-state species. Molecular mixing is modelled using the modified Curl's model. The current computations have been performed via a hybrid Monte Carlo/Finite Volume algorithm. The joint scalar PDF equations are solved using moving particles in a Lagrangian framework, and the velocity field is closed at the second moment level. The redistribution terms are modelled using the Generalized Langevin Model of Haworth and Pope. The principal aim was to investigate the thermo-chemical effects, and thus a steady-state calculation procedure is adopted. The computations are shown to reproduce experimental mean and rms values of velocities, temperature, mixture, and species mass fractions. In particular, mass fractions of CO and NO are well predicted. Conditional PDFs are also well reproduced although uncertainties in boundary conditions influence results close to the bluff body.