M.Sc. Marius Schmidt


work +49 6151 16-28907
fax +49 6151 16-28900

Work L1|08 123
Otto-Berndt-Str. 3
64287 Darmstadt

The reduction of CO2 emissions has become a major issue on a broad area of technologies with economic and social relevance. One of the major contributors to CO2 emissions over the next decades are internal combustion engines and thus the reduction of those emissions is important. Furthermore it is mandatory to improve internal combustion engines with respect to efficiency and low local emissions like NOX and hydrocarbons.

To address these issues a comprehensive understanding of the underlying physical and chemical processes is necessary. Recent advances in the automotive industry have led to the downsizing of the internal combustion engine geometry, which increases the surface-to-volume ratio of the engine. To this regard, near-wall reactions become increasing important for flame quenching and unburned hydrocarbon emissions. In combination with numerical simulation research in this field leads to improved combustion efficiency and engine development.

An optically accessible research engine with quartz-glass liner and piston top is used to investigate the combustion process in a SI or DISI engine. This way a direct investigation from the bottom and the side of the combustion chamber is possible. It is of special interest what effect the impinging flame has on the temperature profile at a wall. The methods used to measure scalar and vector fields are laser induced fluorescence (LIF), the use of thermographic phosphors, and particle image velocimetry (PIV).

Measurements capturing the instantaneous interdependency of the flame position and wall temperature will be used to study near-wall reactions in the optical engine. The 2D temperature distribution at a wall will be measured using the temperature dependency of the fluorescence decay of a thermographic phosphor after excitation with a laser. Simultaneously the position of the flame will be detected using a four shot laser system to excite the hydroxyl (OH) radical and detect the red shifted fluorescence signal with high speed cameras. The data will be used to reveal the effect of flame-wall interaction at different engine speeds and exhaust gas recirculation numbers.