Parallel unstructured-grid finite-volume method for turbulent nonpremixed flames using the flamelet model

A parallel unstructured-grid finite-volume method has been developed to accurately and effectively handle physically and geometrically complex turbulent reacting flows. The parallel algorithm has been implemented to improve the computational efficiency of the unstructured-grid flow solver. The strong density - pressure - velocity coupling at all speeds is handled by the multiple pressure-correction method. In dealing with the turbulent non-premixed flame fields, the turbulence - chemistry interaction is represented by the laminar flamelet model, which could be the optimum choice between accuracy and economy. Numerical results indicate that the present approach reasonably well predicts the overall features of the three-dimensional turbulent nonpremixed flame. However, there exist noticeable deviations between prediction and measurement. Based on numerical results of turbulent reacting flows, detailed discussions is given about the prediction capabilities and limitations or defects of the present numerical and physical models.