Measurements of spray flame properties in a jet-engine combustor

Detailed measurements of the mean temperature and species concentration of carbon dioxide, carbon monoxide and oxygen have been obtained in an actual jet-engine combustor called straight flow combustion chamber manufactured by Rolls Royce company. This type of experiment provides useful information which are essential to facilitate understanding of the spray combustion in this real combustor where the three dimensional nature of the primary zone causes intense combustion followed by dilution where the flow pattern can be a strong function of geometry. The combustor was equipped with a twin-fluid swirl atomizer fuelled with kerosene fuel. The scheme of measurements has been arranged to study the effect of air-to-fuel ratio and droplet size on the flame behaviour. Four flame configurations are identified and correspond to a small droplet size of 40 μm Sauter mean diameter with high (260 kg/h) and low (165 kg/h) combustion air. The large droplet size of 50 μm was used with the same two flow rates of combustion air. In all experiments the mass flow rate of fuel was kept constant at 2.06×10^-3 kg/h and the flames were stabilized by a swirler having a swirl number of 1.31.