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This work proposes a chemical mechanism tabulation method using artificial neural networks (ANNs) for turbulent combustion simulations. The method is employed here in the context of the Large-Eddy Simulation (LES) -Probability Density Function (PDF)approach and the method of stochastic fields for numerical solution, but can also be employed in other methods featuring real-time integration of chemical kinetics. The focus of the paper is on exploring an ANN architecture aiming at improved generalisation, which uses a single multilayer perceptron (MLP) for each species over the entire training data set. This method is shown to outperform previous approaches which take advantage of specialisation by clustering the composition space using the Self-Organising Map (SOM).The ANN training data are generated using the canonical combustion problem of igniting/extinguishing one-dimensional laminar flamelets with a detailed methane combustion mechanism, before being augmented with randomly generated data to produce a hybrid random/flamelet data set with improved composition space coverage. The ANNs generated in this study are applied to the LES of a turbulent non-premixed CH 4 /air flame, Sydney flame L. The transported PDF approach is used for reaction source term closure, while numerical solution is obtained using the method of stochastic fields. Very good agreement is observed between DI and the ANNs, meaning that the ANNs can successfully replace the integration of chemical kinetics. The time taken for the reaction source computation is reduced 18-fold, which means that LES-PDF simulations with comprehensive mechanisms can be performed on modest computing resources.

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