ABSTRACT
Several factors justify the current interest in hydrogen-fueled surface transportation. When combusted with air, hydrogen offers emissions free of the major contributors to atmospheric pollution: unburned hydrocarbons, carbon monoxide, carbon dioxide, oxides of sulfur, and greatly reduced amounts of oxides of nitrogen under normal operating conditions. A combined review of the most common engine cycles and the general combustion properties of fuels leads to an appreciation of the advantages and disadvantages of hydrogen as a fuel for internal combustion engines. The chapter shows that the engine could deliver more power per stroke with hydrogen. The combustion properties of hydrogen indicate an improved thermal efficiency of the diesel cycle fueled by hydrogen as compared to gasoline, and some corroborative evidence has been reported. The low energy of ignition and the wide flammability limits of hydrogen have been noted earlier as attributes of hydrogen as an internal combustion engine fuel.
