Comparisons of LPDF and MEPDF for lifted H2/N2 jet flame in a vitiated coflow
Transported probability density function (PDF) approach have been applied broadly and effectively for modelling turbulent reacting flows. The discretization of this approach is done with two methods, Multi-Environment Eulerian (MEPDF) and Lagrangian Monte-Carlo (LPDF) which each method has advantages and disadvantages. The aim of this work is to investigate the capabilities of each method in predicting hydrogen combustion in a turbulent flame. A comparative study has been adopted between the two methodsby equivalent physical models and numerical parameters. The study was applied in the diffusion turbulent flame of hydrogen into a vitiated of hot coflow with modified K-epsilon model of turbulence. The chosen mixture model is the IEM (Interaction by Exchange with the Mean) with mixing constant (2.1). The number of environment in the first approach is (2.0). The model was solved in this work by the commercial CFD code, ANSYS fluent and the chemical reaction mechanism injected is GRI mech 2.1. The numerical results for temperature and species mass fractions are presented and compared with the experimental data. The comparison shows that the eulerian method gives better predictions than the lagrangian method. The advantages and disadvantages of both models are discussed in detail in relationship to the results.
PDF transport, MEPDF, LPDF, vitiated coflow, k-epsilon modified
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