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How to Save Fuel with Hydrogen Injection
The addition
of hydrogen injection to a normal fuel injected, spark ignition, gasoline
fueled, engine will not likely increase its efficiency unless it is
operated primarily under stressed combustion. However
the benefits of hydrogen injection can be taken advantage of by
manipulating the operating parameters of the engine.
It is well known that a gasoline
engine produces the greatest torque with a stoichiometric air/fuel mixture, but can be much more
efficient when run with an ultra-lean mixture, especially at cruise throttle settings. The reason for this is that the
ultra-lean mixture opens the throttle further and reduces the vacuum in
the engine manifold that causes the engine to use up horsepower to suck
the combustion air into the combustion chamber. The ultra-lean mixture reduces the
horsepower used in sucking in the air.
Running an ordinary engine with
an ultra-lean air/fuel mixture is the job of the Hydrogen Boost
system. Everything possible must
be done to prepare the mixture to combust. The fuel heater heats the gasoline to
the highest possible temperature without causing vapor problems within
the fuel injection system, so that when the hot fuel is injected, more of
it will vaporize. The fuel
vaporizing system (usually hot fuel returning to the fuel tank) vaporizes
more fuel that is brought to the engine through the evaporative emissions
control system. This combination
vaporizes as much fuel as possible to prepare it for combustion (liquid
fuel does not combust until it is vaporized, either in the combustion
chamber or before it gets there).
The hydrogen injection accelerates ignition of the vaporized fuel
when the spark plug fires, similar to the way lighter fluid accelerates
the lighting of barbeque briquettes.
This forces the ultra-lean air/fuel mixture to ignite when normally
this lean of a mixture would simply misfire.
To create the desired ultra-lean
air/fuel mixture in a fuel injected engine the electronic control circuit
of the Hydrogen Boost system does two things. First it “kills the stoichiometric
police” by disconnecting the oxygen sensor mandated by the government to
guarantee a stoichiometric mixture (no excess oxygen
or fuel going out the exhaust pipe).
Secondly it modifies the signal from the MAF (mass air flow) or
MAP (manifold absolute pressure) sensor going to the ECU (engine control
unit) or PCM (power control module) thereby telling the engine computer
that less air is present than there really is. This causes the computer to demand less
fuel to be injected into the engine and therefore a leaner mixture. The electronic control circuit can be
adjusted on the fly from the driver’s seat and in response to the feel of
the engine’s performance. The
mixture is usually set at the leanest mixture that enables a smooth power
output. This ultra-lean mixture
also keeps the combustion temperature down to a point where NOx (nitrogen oxides) emissions are avoided.
The permanent engine treatment
component of the Hydrogen Boost system reduces friction and drag inside
the engine, which further increases the engine’s efficiency. And another component of the Hydrogen
Boost system, the Scangauge, helps the driver
monitor his mileage and helps him learn more efficient driving
techniques.
Hydrogen injection in a diesel engine can, however, cause an increase in efficiency
(amount of work done per unit of fuel combusted) because compression
ignition is already a stressed combustion condition that benefits with
hydrogen injection. However the
fuel heater and permanent engine treatment components of the Hydrogen
Boost system give additional improvements.
Lastly the latest addition to the Hydrogen Boost system, in both
gasoline and diesel systems, a manifold vacuum switch (pressure switch
for turbocharged diesel engines) is used to turn off the Hydrogen Generator
component of the Hydrogen Boost system, whenever the cost of producing
the hydrogen is not outweighed by the benefits. At idle and low cruise power settings the
benefits of hydrogen injection are minimal because there is little fuel
being combusted.
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