Simulations of extinction and re-ignition phenomena in turbulent piloted methane-air jet diffusion flames (Sandia flames D, E and F) are performed using the One-Dimensional Turbulence (ODT) model. Conditional statistics of thermochemical scalars at various downstream distances are obtained from multiple realizations of ODT solutions. Comparison between ODT predictions and experimental data on flames D, E and F show that ODT reproduces very well intermediate mean and rms conditional statistics, especially for reaction intermediates such as H_2 and CO. Changes in thermoscalars' profiles reflects the different finite-rate chemistry effects at different downstream conditions and Reynolds numbers. One important effet of finite-rate chemistry is the presence of extinction and later downstream reignition, especially for the higher Reynolds number flames, E and F. Bi-modal shapes of the conditional PDF's at intermediate downstream conditions for flames E and F indicate the presence of both extinguished and reigniting flames. The results show that the computations yield more extinction for the lower Reynolds flames, D and E than the experiment. Further downstream, the shift of the conditional PDF's towards a single peak mark the completion of the re-ignition process. The ODT model is able to predict extinction and re-ignition in jet diffusion flames using the same model parameters adopted for other flames.
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