Experimental study and numerical validation of oxy-ammonia combustion at elevated temperatures and pressures

摘要

The combustion of fossil fuels, which are mostly based on hydrocarbon chains, produces large quantities of carbon dioxide which is a major contributor to the global warming. Due to alarming concerns, initiatives are taken to promote the use of 'zero-carbon fuel'. The use of ammonia as an alternative fuel in combustors like gas turbines and spark-ignition engines have already been tested. As high pressures and temperatures are encountered in these combustors, it is essential to find laminar flame speed data for ammonia combustion at these conditions. The present study focuses on performing experiments at elevated conditions for different equivalence ratios in a constant volume spherical chamber. A literature study was performed to select and evaluate the most recent kinetic mechanisms for ammonia combustion under these conditions. A sensitivity analysis highlighting the key reactions for two of the schemes has been performed. A range of exponential factors for temperature and pressure which is used to calculate the flame speeds for a given reference conditions : alpha and beta have been determined. (C) 2021 The Combustion Institute. Published by Elsevier Inc. All rights reserved.