The ppt is about using hydrogen as a fuel in a SI engine in dual fuel mode. The various methods are suggested and also the effects in emission characteristics and difficulties.

1. TITLE: PETROL ENGINE WITH HYDROGEN IN
A DUAL FUEL MODE
Presented By:
Mayur.P.Suvarna
Vtp No:
2601

2. DRAWBACKS OF HYDROGEN POWERED AUTOMOTIVE ENGINES
1. The fuel cell: still expensive and not sufficiently profitable
>The fuel cell is very expensive (although some car manufacturers announce considerable price cuts) and is
delicate and complex to operate. It also requires the use of precious metals, such as platinum, to manufacture
it.
2. Limited range
>One kilogram of hydrogen releases as much energy as three litres of petrol. However, hydrogen is the
smallest and lightest element in the universe, and its energy density (energy per unit of volume) is very low.
That means we need to store a lot of it under high pressure (700 bar) to obtain the amount needed to operate
a car.
3. Risks
>This high-pressure tank presents an additional risk if the vehicle is in a crash, especially as hydrogen is very
volatile and highly inflammable.
4. Few service stations.
5. Storage problems.
6. Nox produced is more.

3. WHY DUAL FUEL ENGINES ARE REQUIRED?
• World war 1 was led to invention of dual fuel engine , due to shortage of liquid fuels at that
time.
• A dual fuel engine is constructed so that the various accepted alternative fuels can burn
efficiently . A strengthening of the engine is necessary in order to meet these higher
demands.
• The motivation to run si engine on gaseous fuel is largely economic.
• Interest in the efficient utilization of gaseous fuel resources for the production of power using
conventional internal combustion engines.
• Demand for economic and cost efficient fuel.
• The major advantages of the dual fuel engines are its ability to use a wide range of gaseous
fuels and also to produce smoke levels lower than that of conventional gasoline engine.
• Many investigators have reported acceptable performance and lower emission characteristics
with dual fuel engines with gaseous fuels like LPG, hydrogen and biogas.

4. WHY HYDROGEN USED IN SI ENGINES ?
• High octane number i.e 120 whereas for gasoline its 87 and above.
• Higher self ignition temperature for hydrogen its
500-536 °C whereas for gasoline its 247-280°C .
• Requirement of Spark Plug.
• As use of gasoline can be limited.
• Due limited resources its necessary to find the alternative fuel.

5. METHODS BY WHICH HYDROGEN CAN BE USED IN SI ENGINE
1.Manifold introduction of hydrogen
In this there is a high risk of pre-ignition and backfire ,so hydrogen is cold stored
and with the help of valve the hydrogen is injected.
2.Direct injection of hydrogen into the cylinder.
Liquid is stored in the form of liquid hydrogen in the cryogenic container and with
high equipped setup.
3.Dual Fuel mode
Mixture of Hydrogen and gasoline is used for the combustion with different
methods.

7. 1.DIRECT INJECTION OF HYDROGEN
• Works similar to normal si engine.
• Gasoline is injected into the intake manifold to form a better air fuel
mixture.
• The mixture is inducted into the combustion chamber.
• The high pressure hydrogen is injected into the combustion chamber.
• The mixture is compressed and ignited with the help of spark plug.
• Here the quantity of hydrogen is controlled by ECU with respect to
increase in load.

8. BENEFITS OF THIS TYPE OF METHOD
• Direct injection led to 42% of volumetric efficiency.
• Distribution of hydrogen well organized so to control the combustion and also
injection timing matches the ignition area.
• Flexibility in hydrogen flow control.
• Blend of gasoline and hydrogen mixture improve the burning rate of mixture which
decreases the misfire rate.
• Mixture burns more sufficiently which led to high energy travel in shorter period of
time.
• Signifies the enhancement on the conversion efficiency from energy to work in
Otto cycle

10. 2.SPLIT HYDROGEN DIRECT INJECTION
• It’s the modification to the gasoline direct injection system.
• Works similar to the gasoline direct injection system.
• An high pressurized hydrogen injector is added into the combustion chamber.
• Hydrogen fuel injector is placed at an angle to better mixing with the gasoline
air mixture and for the better combustion.

11. BENEFITS OF SPLIT HYDROGEN DIRECT INJECTION
METHOD
• When compared to hydrogen direct injection can form well stratified condition or
mixture.
• Which results the combustion more complete and more faster.
• Can add early spray for forming the homogenous mixture which speeds up the
combustion.
• Led to increase in break thermal efficiency and increase in torque.
• Reduces the quenching distance which reduces the maximum temperature due
which Nox emissions are reduced.

12. Split Hydrogen Direct Injection Representation

13. 3.PILOT INJECTION OF GASOLINE
• Gasoline is used as pilot fuel with hydrogen being used as the inducted fuel in dual fuel engine.
• Gasoline engines, however, can be made to use a considerable amount of gaseous fuels in the dual fuel
mode.
• The mixture is then ignited by a small amount of gasoline, called the pilot fuel.
• The mixture of pilot fuel and hydrogen gas can be varied with respect to different load condition.
• Nowadays this method is modified with supply of hydrogen gas via electrolysis process.
• This reaction takes place in a unit called an electrolyzer.
• Electrolyzer is small, appliance-size equipment and well-suited for small-scale distributed hydrogen
production.

16. BENEFITS OF PILOT INJECTION OF GASOLINE
• Lower usage and effective use of gasoline
• CO and HC emissions were reduced at all different loads.
• Increase in brake power thermal efficiency due to increase in
calorific value of the value.
• Compact arrangement for the electrolyzer arrangement.

18. 4. GASEOUS FUEL + HYDROGEN AS DUEL FUEL
• CNG is cheaper than the conventional petroleum based gasoline fuel.
• Natural as low flame speed hence hydrogen is used.
• Major drawbacks with CNG are lower power output and slow acceleration. Many researchers have
addressed these problems to a larger extent.
• Hydrogen and CNG were mixed in a developed mixer and supplied through the inlet manifold system.
• The combustion analysis carries out for different rates of hydrogen addition.

19. BENEFITS OF GASEOUS + HYDROGEN FUEL
• In general, it is found that HC, CO2, and CO emissions decreases with increasing volume of H2, but
oxides of nitrogen (NOx) emissions generally increase. If a catalytic converter is used, NOx emission
values can be decreased to extremely low levels.
• Increase the level of turbulence is limited , if also increased which led to increase in heat transfer and
increase in temperature which further increases Nox, so this can be reduced by this method.
• Other performance parameters are also been improved with help of this process.

23. Mazda rotatory engine working on dual fuel principle