Identifying the skeleton mechanism for oscillatory combustion with functional weight analysis

In this work, a functional weight (FW) method is proposed to identify the primary mechanism of oscillatory combustion in MILD combustors. Inter-species interactions are quantitatively measured by analyzing combustion oscillation data to recognize the importance of each link. Detailed statistics of the functional weight in the oscillatory combustion mechanism revealed that the weight distributions are highly heterogeneous, with a very limited part of the inter-species links dominating. This allowed us to easily identify important processes and build a skeleton mechanism for oscillation prediction. Case studies are conducted on methane- and propane-fueled MILD combustion systems, where oscillatory dynamic behavior is reported. It is found that the skeleton mechanism obtained can eliminate more than 90% of the reactions, keeping good oscillation prediction ability, and the recognized important reactions are in perfect agreement with the related kinetic investigations.