Soot Formation and Emission from JET A-1 and a 30 % HEFA blend in a multisector combustor at realistic operating conditions

Abstract

The production and emission of soot from Kerosene JETA1 and a blend of a different JET-A1 and 30 % HEFA was investigated in a realistic multisector combustor of Rolls-Royce Deutschland. Soot concentration measurements were performed at the exit as well as in the optically accessible primary zone of the combustor. There, information of soot mass concentration is available from measurements using Laser induced incandescence and Laser extinction. At the exit of the combustor, soot particles were measured with a scanning mobility particle sizer. This resulted in particle size distributions from which soot number and mass concentrations were calculated. Within the pressurized combustor, low load points, scaled cruise and high load points were operated. For the investigated operating range which reaches to ~50 % of max pressure but preserves engine AFR, up to 75 % reduction of both soot particle mass and number EI were observed for the HEFA blend in part load and 50 % at the scaled high-power condition. However at the end of the primary zone, a reduction increasing with soot concentration and fuel load was recorded. This guides attention to the different oxidation characteristics for the fuels in the investigated combustor. Accordingly, larger particles were consistently measured at the exit for the HEFA blend.