What are the advantages and disadvantages of using hydrogen as an I.C.Engine fuel?
Explain one method by which hydrogen can be used in C.I. Engine.
Advantages of using hydrogen as I.C. engine fuel
(i) Low emission
(ii) Fuel availability; There are a number of different ways of making hydrogen,
including electrolysis of water.
(iii) Fuel leakage to environment is not a pollutant.
(iv) High energy content per volume when stored as a liquid. This would give a large
vehicle range for a given fuel tank capacity.
Disadvantages
(i) Storage problem; Hydrogen can be stored as a cryogenic liquid or as a
compressed gas. This will required a thermally super insulated fuel tank or high
pressure vessel.
(ii) Difficult to refuel & the possibility of detonation.
(iii) Poor engine volumetric efficiency.
(iv) Fuel cost would be high at present day technology and availability.
(v) High NoX emission because of high flame temperature.
(vi) Can detonate.
Use of hydrogen in C.I. engine
Hydrogen is introduced directly into the cylinder at the end of compression. Since the
self ignition temperature of hydrogen is very high, the gas spray is made to impinge
on a hot glow plug in the combustion chamber, that is by surface ignition. It is also
possible to feed a very lean hydrogen air mixture during the entrance into an engine
and then inject the bulk of the hydrogen towards the end of hydrogen stroke.
