Dr.-Ing. Pascal Johe
Contact
johe@rsm.tu-...
In the context of climate change due to an increasing amount of greenhouse gases in the atmosphere, the reduction of CO2 emissions has become a main topic in political and social discours. Since a large part of global CO2 emissions arise from combustion processes, the development of new combustion concepts is indispensable. This requires a profound comprehension of the relevant physical and thermochemical mechanisms occuring during combustion. In many modern, technical combustion systems, such as internal combustion engines and gas turbines, these processes are affected by solid walls. Rapidly decreasing temperatures close to walls lead to wall heat losses, soot deposits and increased emissions of unburned hydrocarbons due to quenching of reaction processes. Furthermore, these flame-wall interaction processes are of growing relevance considering the recent trend towards higher power densities in technical combustion systems.
In order to achieve a comprehensive understanding of flame-wall interaction processes, investigations on generic test cases are carried out. Previous investigations on atmospheric flames propagating parallel to walls – the so-called sidewall quenching process – are supplemented with experiments at closer to reality conditions. For this purpose, the existing sidewall quenching test case is adapted to a pressurized confined configuration which enables experiments at higher turbulence levels and Reynolds numbers in a pressurized environment. Optical access to the quenching wall allows the application of advanced laser diagnostics to simultaneously measure multiple parameters, such as gas phase temperatures, concentrations, species distributions and spatial flow fields. The acquired measurement data aid to understand the ongoing processes and serve as validation data for numerical combustion simulations.