2. Hydrogen combustion theory

In this section, the physico-chemical properties of hydrogen are examined in order to understand why it is a decarbonized fuel suitable for the internal combustion engine, and to identify the differences with conventional fuels. Firstly, the density and diffusion capacity of hydrogen are studied, as these characteristics play a major role in the mixing process with air. Next, the flammability, ignition energy and self-ignition propensity, which govern ignition and combustion initiation, are examined. Finally, laminar and turbulent flame velocities, as well as flame jamming distance, are analyzed, as they control the progress and termination of combustion.