Methodology for the Study of Hydrogen Combustion in an Optical Spark Ignition Engine

The use of hydrogen as a fuel in internal combustion engines represents a promising alternative for reducing CO2 emissions. To optimize its efficiency and better understand the phenomena associated with its combustion, it is essential to have advanced visualization techniques for a better understanding of the processes involved. This paper presents the methodology used in the development of an optical engine for the study of hydrogen combustion, designed from a 454cc single-cylinder engine. The configuration of the optical system is described, which includes the use of high-speed cameras to capture the spark plug activation as well as the flame propagation in the combustion chamber. The engine has two optical accesses, one through the piston and one at the top of the cylinder that allows side viewing of the combustion chamber. In addition, the experimental procedure that alternates combustion cycles with motoring cycles, the determination of the air-hydrogen ratio with which the engine is operating, the analysis of the combustion process, and the image processing used are detailed. As a conclusion of the work, it can be said that an optical engine has been manufactured, and a test methodology has been developed for the study of the hydrogen combustion process in spark ignition internal combustion engines.