Staff

The optically accessible research engine at TU Darmstadt (Fig. 1) uses an automotive engine with a quartz glass cylinder liner and piston for optical access. The optical engine operates under engine motored or fired and port fuel injection or direct injection conditions and allows a number of simultaneous diagnostics to be performed. Along with the acquisition of temperature and pressure, advanced optical diagnostic techniques including particle image velocimetry (PIV), laser-induced fluorescence (LIF), thermographic phosphor thermometry (TPT), Mie scattering imaging, diffuse back illumination (DBI), and tunable diode laser absorption spectroscopy (TDLAS) are used to gain insight into the fundamental characteristics of engine operation.

In-cylinder flows play an important role in the combustion process of spark ignition engines. Using the aforementioned methodologies, the interaction between the flow and the other combustion processes, namely direct injection spray morphology, spark discharge, and flame growth, are investigated. In particular, understanding the effects of different strategies for sustainable ICE combustion on cycle-to-cycle variations, such as exhaust gas recirculation, or renewable fuels, for example hydrogen, are critical for the energy transition of the near future.