Experimental investigation of the interaction between swirl stabilized pressurized flames and effusion cooled walls related to thermochemical states, reaction rates and pollutant formation

点击翻译按钮获取中文摘要

The objective of this project is to experimentally investigate the interaction between lean turbulent swirling flames being relevant for aero engines and effusion cooling of combustor walls. The research focus is on the impact of effusion cooling upon local thermochemical states, reaction rates and primary formation of carbon monoxide as important pollutant species. Demands for aero engines are increasing, and result from the agreement targets of ACARE2020 or the Flightpath 2050. These demands enforce a replacement of rich-quench-lean combustion by lean combustion concepts, due to their potential for much decreased formation of nitric oxides. As a drawback, the amount of available cooling air decreases and reaction zones are shifted closer to the combustor walls. As a consequence, the thermal load at the walls is strongly increased which is intensified additionally by higher cooling air temperatures due to higher pressure ratios as needed to improve fuel consumption. Cooling air streams are not only highly important for the thermal management, but influence as well combustion chemistry. Whereas efficient cooling concepts have been investigated broadly in the past, the impact of cooling air flows upon local thermochemical states, reaction rates and pollutant formation has hardly been investigated although these issues are highly relevant for meeting future environmental targets. This project aims to focus on these challenging issues. For this purpose laser diagnostics are applied to a pressurized combustor where important features of gas turbine combustion are mimicked. Experimental results will serve for an improved understanding of the interlinked physical and chemical processes and unique experimental data will support validation of numerical combustion modelling.