Thèse de doctorat
Résumé : A lot of research effort is spent worldwide in order to reduce the environmental impact of the transportation and power generation sector. To minimize the environmental pollution the role of hydrogen fuelled gas turbines is intensively discussed in several research scenarios, like the IGCC-technology or the application of hydrogen as large scale storage for renewable energy sources. The adaptation of the applied gas turbine combustion chamber technology and control technology is mandatory for a stable and secure low NOx operation of a hydrogen fuelled gas turbine.

The micromix combustion principle was invented at Aachen University of Applied Sciences and achieves a significant reduction of the NOx-emissions by the application of multi miniaturized diffusion-type flamelets. Based on the research experiences, gained during the two European hydrogen research programs EQHHPP and Cryoplane at Aachen University of Applied Sciences, the intention of this thesis was to continue the scientific research work on low NOx hydrogen fuelled gas turbines. This included the experimental characterization of the micromix combustion principle, the design of an improved combustion chamber, based on the micromix combustion principle, for industrial gas turbine applications and the improvement of the gas turbine’s control and metering technology.

The experimental characterization of the micromix combustion principle investigated the impact of several key parameters, which influence the formation of the NOx-emissions, and allows therefore the definition of boundary conditions and design laws, in which a low NOx operation of the micromix combustion principle is practicable. In addition the ability of the micromix combustion principle to operate at elevated energy densities up to 15 MW/(m2bar) was successfully demonstrated. The improved combustion chamber design concept includes the experiences gained during the experimental characterization and covers the industrial needs regarding scalability and manufacturability.

The optimization and testing is done with an Auxiliary Power Unit GTCP 36-300. The original kerosene fuelled gas turbine was modified for the hydrogen application. Therefore several hardware and software modifications were realized. The improved gas turbine’s control and metering technology enables stable and comparable operational characteristics as in kerosene reference. An improved hydrogen metering unit, which is controlled by the industrial Versatile Engine Control Box, was successfully implemented.

The combination of the micromix combustion technology and of the optimized control and metering technology allows a stable, secure and low NOx hydrogen fuelled gas turbine operation.