Started in the year 2004, the EU research-project HyICE for the development of innovative hydrogen combustion processes was already introduced in the last annual report. The project was also continued this year with numerous activities in simulation and test bench testing. Additionally to the experiments carried out at a one-cylinder research engine for the first time a research engine in optical configuration was available for further investigations.
The major task of the institute in this project is the analysis of the potentials of hydrogen direct injection, with the primary objectives of the maximization of efficiency and performance and the minimization of emission.
This year, the main focus at the one-cylinder research engine was the high load performance with hydrogen direct-injection. Thereby the potential of hydrogen could be illustrated theoretically as well as under real-world conditions on the test bed.
A further improvement of the development process could be achieved with the introduction of laser measurement techniques for the analysis of mixture formation- and combustion processes. Therefore a test bed with an optical engine was set up. The optical setup provides an insight into the combustion chamber in real engine operation. Together with the engine a measurement system for laser induced fluorescence (LIF) was built up.
This system allows the two dimensional visualization of the local air/fuel ratio in the combustion chamber by adding a tracer to the fuel. Furthermore it is possible to determine the propagation of the flame front via selective excitation of the OH-radical.
The main focus of the CFD-simulation this year was the optimization of the mixture formation process. By applying the results of the optical engine it was possible to validate the models used. The excellent correlation between the results of LIF measurement and those of the 3D-CFD-simulation models used in the project could be proven by directly comparing typical operating points.