Comparative study of modeling a hydrogen nonpremixed turbulent flame

The topic of this work is the numerical simulation of a turbulent nonpremix ed hydrogen (H-2) jet flame with different combustion models. The predictio ns are validated against existing experimental data provided by Raman and l aser Doppler anemometry (LDA) measurements for a turbulent jet hydrogen-air diffusion flame [1, 2]. In particular, a comparison of two "advanced" turb ulent combustion models is presented: These are a probabilistic Euler Lagra ngian (PEUL) model based on the idea of Lagrange interaction by exchange wi th the mean (IEM), and a model based on the scalar probability density func tion (PDF) transport equation for the thermochemical variables, which is so lved using a Monte Carlo method. In addition, a "standard" Eddy Dissipation Model with a single-step reaction is considered. The numerical results for mean velocity components, turbulent kinetic energy, mixture fraction, temp erature, and major chemical species are presented and compared with the exp erimental data. The goal of the work is to investigate the capabilities of the used models in predicting hydrogen combustion in a jet flame. This simp le geometry allows for reliable flow simulations. Regarding the basic test case under consideration, the results obtained by the PEUL computations and the Monte Carlo simulation are in good agreement with experimental data. T he comparison shows that both probabilistic methods give better predictions than the "standard" model. The advantages and disadvantages of the models are discussed in detail in relationship to the results. It is possible to d raw conclusions for modeling improvements. The improved models should be ab le to be applied also to more complex geometries. (C) 2000 by The Combustio n Institute.