Technical Paper
Hydrogen Admixture Strategies for Small-Scale Cogeneration Gas Engines: A Comparison between different Engine Combustion Processes
2023-06-26
2023-01-1206
Cogeneration represents a key element within the energy transition by enabling a balancing of the long-term fluctuations of regeneratives. Regarding the expected increase of hydrogen share in natural gas pipelines in Germany, this work deals with investigations of hydrogen-associated advantages for the lean and stoichiometric operations of natural gas cogeneration engines, in relation to numerous challenges, such as the efficiency-NOx trade-off. Charge dilution is commonly regarded as one of the most effective ways for improving thermal efficiency of spark-ignition gas engines. While excess air serves as a diluent in the lean combustion process, stoichiometric combustion dilution may be obtained by exhaust gas recirculation (EGR). Combining hydrogen addition with mixture dilution is an appealing approach for a better handling of the efficiency-emissions trade-off.