Comparison between a composition PDF transport equation model and an ASOM model for simulating a turbulent jet flame

A composition PDF transport equation (PDF) model and an algebraic second-order moment (ASOM) model of turbulent combustion are used to simulate a methane-air turbulent jet flame, measured by the Sandia National Laboratory. In most regions, both PDF and ASOM predictions are in agreement with the experimental data with not too much difference. The PDF modeling results give the second-order moments with distributions having a similar trend as those given by the ASOM closure model. Although in general the PDF modeling results are somewhat better than the ASOM results, but considering that the computation time of the ASOM model is almost in two orders of magnitude smaller than that of the PDF model, the ASOM model is suggested for simulating large-size engineering facilities.