The Measurement and Prediction of Gaseous Hydrocarbon Fuel AutoIgnition Delay Time at Realistic Gas Turbine Operating Conditions,” ASME Paper

ABSTRACT Auto-ignition delay time measurements have been attempted for a variety of gaseous fuels on a flow rig at gas turbine relevant operating conditions. The residence time of the flow rig test section was approximately 175 ms. A chemical kinetic model has been used in Senkin, one of the applications within the Chemkin package, to predict the auto-ignition delay time measured in the experiment. The model assumes that chemistry is the limiting factor in the prediction and makes no account of the fluid dynamic properties of the experiment. Auto-ignition delay time events were successfully recorded for ethylene at approximately 16 bar, 850K and at equivalence ratios between 2.6 and 3.3. Methane, natural gas and ethylene (0.5 < φ < 2.5) failed to auto-ignite within the test section. Model predictions were found to agree with the ethylene measurements, although improved qualification of the experimental boundary conditions is required in order to better understand the dependence of auto-ignition delay on the physical characteristics of the flow rig. The chemical kinetic model used in this study was compared with existing 'low temperature' measurements and correlations for methane and natural gas and was found to be in good agreement

DETAILED INTERNAL MEASUREMENTS OF A SIEMENS COMBUSTOR OPERATING AT GAS TURBINE RELEVANT CONDITIONS

ABSTRACT In order to develop liquid fuelled DLE gas turbine combustors, especially to accommodate alternative more environmentally friendly fuels, it is necessary that their operation is well understood. Although CFD can appear to offer many insights into the operation of such burners this is only achieved by applying a number of individual models to predict each stage in the mixture preparation and combustion processes. While each model is validated individually, their overall performance in a complex system is not well understood. This paper therefore presents unique data that can be used to determine the overall validity of CFD predictions of a Siemens combustor. Such data was produced by QinetiQ by making detailed (approximately 200) gas analysis measurements in the interior of the combustor while operating at gas turbine relevant conditions using the Sector Combustion Rig at the GTRC Port Talbot. The data collected shows detailed information regarding the internal processes of the combustor, and is therefore ideally suited to the validation of CFD