Current status of the high-temperature kinetic models of silane: Part I. Pyrolysis

The present work compares the performance of seven reaction models with respect to a large experimental dataset relevant to the high-temperature pyrolysis of both silane (SiH4) and disilane (Si2H6). Their performances were established based on different validation criteria that account for the shape and the amplitude of the validation profile. Then, the model performances were quantified with a global error, which accounts for the experimental uncertainties. The most satisfactory model has a global error as low as 3.1 (i.e., meaning 3.1 times higher than the experimental uncertainty) and the highest fraction (74%) of criteria with a low error (< 2 ), while most of the models have large discrepancies with the validation dataset, global error near 8 and up to 110 for the less accurate model. The origins of these discrepancies are identified with reaction pathway and sensitivity analyses. Among the seven tested model, three main decomposition pathways are evidenced, including one more specific to the models presenting the lowest errors. Based on the global error values, the ability to reproduce all the experimental conditions, and the model analyses, the reaction pathways relevant to the high-temperature pyrolysis of silane and disilane are determined. In addition, the present study provides experimental and numerical guidance for the future developments of silicon hydride reaction models. The limited performance of most of the oldest reaction models may have a significant impact on our current understanding of the pyrolysis and oxidation kinetics of silane. (C) 2020 The Combustion Institute. Published by Elsevier Inc. All rights reserved.