This article provides a comprehensive review of current state of knowledge regarding the ongoing development of hydrogen-fueled internal combustion engines (H2ICE). It describes the key challenges, the resolution of which will determine further progress in the development, practical application, and popularization of H2ICE. The article details the problems associated with creating and optimizing the fuel mixture in the H2ICE cylinder. It also highlights directions for development of hydrogen injection, ignition, and boosting processes. The risks resulting from abnormal combustion processes and the related optimization of combustion strategies in H2ICE are extensively discussed. Problems and difficulties associated with adapting existing engine designs to hydrogen fueling are also considered. Attention is paid to the different degradation patterns and the requirements placed on engine lubricating oil when fueling engines with hydrogen. The article then describes emissions from hydrogen-fueled engines, with particular emphasis on high NOx emissions and methods for reducing those emissions. The last part of the article discusses the influence of hydrogen admixture in various hydrocarbon fuels on combustion processes, engine performance and harmful exhaust emissions into the atmosphere. The article stands out in that it identifies and describes the most important challenges that determine the further development of H2ICE engines. It also provides a comprehensive overview of the current state of knowledge in the field of ongoing development of hydrogen-powered internal combustion engines (H2ICE).
Zbigniew Stępień (Tue,) studied this question.