in their study
employed hydrogen directly in a single-cylinder, air-cooled,
normally aspirated, direct injection diesel engine by heating
the intake air to 80 C with a specifically designed high pressured
H2 injector. Consequently, an increase in 14% of power
with an increase in thermal efficiency from 28% to 43% was
observed. Besides, a decrease of 20% on NOx emission formation
was also obtained. It is possible to use hydrogen in a
dual fuel mode in a CI engine. In this mode, ignition can be
apprehended by diesel pulverization because hydrogen is the
main fuel, and it is recognized as the most sensible method
when combustion permanence is considered. Thus, timing
manifold/port injection, direct hydrogen injection and
continuous manifold injection methods are applied [14].