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The Concept IC Engine
The second really innovative engine design described in
these pages, is the Concept IC Engine , which utilises a
revolutionary new design , to completely transform the
conventional IC engine . The great advantage of this design is
that existing IC engines can be modified to run as Concept IC
engines at minimum cost while at the same time increasing
efficiency by as much as 200% and also reducing fuel emissions
to zero. This may sound far fetched but as you will see , if
you continue to read these pages , a detailed and well
documented rationale is given as to why this engine can and
will work. In fact anyone who can provide a logical and
verifiable refutation of the Concept IC engine shall receive
from me a most abject and humble letter of apology. Studies
have shown , and this may easily be verified from The Colorado
State University Engine Web Site , a link to
which is provided , that IC engines lose 42% of their energy
to exhaust and 28% of their energy to the cooling system. With
more than 500 million cars world wide (not counting buses ,
trains , construction and military transport ) and with this
number constantly increasing there is an urgent need for
better , cleaner , more efficient engines. The Concept IC
engine provides a low cost and highly effective solution to
solving all these problems.
Introducing the Concept IC engine:
Automotive engineering has seen a spate of innovations
in the past decade , MV's (Multiple valve's ) , DOHC's (Double
overhead cams ) , MPFI (Multi-port fuel injection) and DFI
(Direct fuel injection ) which , when combined with stronger
and lighter carbon composites and metal alloys , are rapidly
bringing reciprocating internal combustion engine technology,
as we know it , to a point where the full potential of the
engine has almost been realised. Extensive coverage in
magazines and other media , have reported on almost every
aspect of the working of these innovations and the advantages
their implementation has resulted in , such as better fuel
economy , more power and a cleaner engine. What is less widely
known is the fact that in spite of the huge amounts of money
and man hours spent on researching and implementing these
products the overall efficiency of the RI engine has been
increased by a mere 5%. The engine is now less than 25%
efficient as compared to an original efficiency of less than
20%. The expected improvement in performance has fallen far
below expectations. What is the reason for this ?
Real contribution made by recent
innovations:-
The real contribution that innovations such as DOHC's,
MV's , MPFI and DFI have made to RI engine design has been in
high-lighting and identifying what is not wrong with the
engine. An increase in efficiency of a mere 5 % , or an
overall efficiency of less than 25 % even after the
implementation of the innovations under discussion , has shown
that it is not basically valve over-lap , valve lead , valve
lag , linear to rotary conversion , or any of the
traditionally quoted reasons ,which is responsible for the
poor performance of the engine . To find the underlying causes
behind the inefficiency of the RI engine , it is necessary ,
therefore , to look elsewhere.
Efficiency of the IC engine:-
IC engines lose 42% of their energy to exhaust and 28%
of their energy to the cooling system. Therefore the true
explanation for the poor performance of the engine would seem
to lie in inefficient use of energy and loss of energy through
heat transfer. The loss incurred through inefficient use of
energy is easily understood , compressed fuel and air is
ignited and is then used to propel the piston down the
cylinder with explosive force for a distance of just a few
inches after which all further energy developed by the fuel is
lost and in fact becomes a liability since the piston has to
reverse direction , a process which is inhibited by the
pressure of trapped gases on the piston head. The reason that
energy loss to heat transfer has been tolerated , and even
welcomed by engineers , is a little more involved and will be
referred to later on in the article. Notwithstanding the
improvements made to the RI engine we have to ask ourselves ,
and this is the million dollar question , is this really the
limit of performance of the reciprocating internal combustion
engine, does this mark the end of the road for this more than
200 year old concept , some entrepreneurs seem to think not ,
they have come up with the idea of a concept IC engine.
Comparison of the IC engine with a
gun:-
The comparison between a gun and the reciprocating
internal combustion engine is appropriate , the piston can be
likened to a bullet or projectile, the cylinder to a barrel
and the fuel - air , mixture to the explosive propellant. The
theory underlying concept IC engine technology has been
established , to put it simply , on the concept of the
recoilless gun. The reduction of recoil in the recoilless gun
is due to the fact that the mass/velocity of the escaping
gases is engineered to equal or approximate the mass/velocity
of the projectile , thereby canceling each other out , the
velocity of the escaping gases can be increased by use of a
venturi or nozzle. Recoilless Guns (Click to link to
article on recoilless guns.)While it is true that there is a
certain reduction in the muzzle velocity of a recoilless gun ,
when compared to a conventional cannon of similar caliber , it
should be understood that this reduction is dependent on
several factors , the most important of which is the length of
the barrel. This is because muzzle velocity is contingent on
the velocity of the propellant gases behind the projectile and
the pressure generated , this is significant only in a gun
with an appreciable barrel length. The fact that most engines
have cylinders of extremely short length ( the throw of the
piston in a conventional engine is only four to five inches on
average) makes it possible to seriously consider applying
recoilless technology to the reciprocating internal combustion
engine. In a conventional reciprocating internal combustion
engine, the piston is forced down the cylinder by the
expanding gases and the pressure they generate. As soon as the
piston reaches BDC however , the velocity of the gases comes
down to zero , and can perform no further useful work , and
the pressure becomes a liability , since the movement of the
piston has now to be reversed .
Working of the Concept IC engine:-
By contrast the concept internal combustion engine
incorporates a slide door or sleeve type valve which
completely opens, (providing unrestricted passage to the
exhaust gases ) onto a nozzle and is substituted for the
regular type of exhaust valve which only partially opens ,
this exhaust valve is opened after ignition of the fuel- air
mixture , resulting in the explosive expulsion of gases
through the nozzle , the velocity of these escaping gases
result in the piston being pushed down the cylinder in an
equal and opposite reaction.. (This is in conformance with
Newton's third law which states that for every action there is
an equal and opposite reaction. In the case in point it is the
velocity of the escaping gases which constitute the action and
the force exerted on the piston head the reaction.) This is
due to the fact that (a) the exhaust valve is opened only
after ignition has taken place , meaning that maximum pressure
has already been achieved within the cylinder and (b) the
velocity of the escaping gases push the piston down the
cylinder with approximately the same force as they would exert
if the valves were closed and the gases expanded in a confined
space as happens in a conventional engine, the length of the
cylinder being too short to appreciably affect the velocity
with which the piston is forced down the cylinder .
The most significant improvement offered by the
Concept IC Engine:-
The most significant improvement that the concept IC
engine has over conventional RI engines is that the explosive
ejection of hot exhaust gases can be used to efficiently power
a turbine which in turn can run the auxiliary devices which
are at present powered by the main engine, such as the
turbo-charger, How
Turbo Chargers work. (click on link for article on Turbochargers.) the dynamo, the oil-pump,
water pump ,cooling system etc., The power output from the
turbine can also be harnessed to augment the main power unit
output by being linked to a generator which would then run
electric motors directly linked to the wheels , if the main
piston unit is also linked to a generator the result would be
an almost soundless , and very efficient power plant run on
the lines of a diesel electric train power plant. The concept
IC engine therefore , in effect has two engines , the primary
or piston engine and the secondary or turbine engine, which
are powered using the same amount of fuel needed to run a
conventional reciprocating internal combustion engine.
Therefore the concept IC engine should in theory , be more
effective than present day reciprocating internal combustion
engine designs, and will make use of a lot of the energy which
is at present wasted. In conventional engines 42% of the
energy generated is lost to exhaust , and 28% to the cooling
system, by using energy which would otherwise be wasted , and
improving on it , the recoilless engine, could be a 100% more
efficient than present day conventional engines. In
multi-cylinder recoilless engines , the secondary turbine unit
might in fact function more efficiently than the primary
piston unit, because of the provision of a continuous flow of
hot exhaust gases at velocity to power the turbine . The
Turbine Engine for cars
Power stroke in an IC engine
examined:-
If we examine in detail , the power stroke in a four stroke cycle of the RI engine the concept of a recoilless engine , and why it can work , becomes clearer., We find that ignition is intitiated at a minimum of 20 - 30 degrees before TDC , the piston then continues up the cylinder reaches TDC and then reverses direction traveling down the cylinder , valve lead or the opening of the exhaust valve in order to relieve pressure on the piston head has to be initiated in the same stroke at a minimum of 50 degrees before BDC , if this were not the case the piston head would be damaged or cracked due to the conflicting stresses. Thus taking the full stroke to be 180 degrees , we find that power is available for roughly 130 degrees. In a concept IC engine , the exhaust valve would be fully opened after ignition and conventional power (i.e with valves closed ) would be available for 80 to 90 degrees as compared to the 130 degrees of the conventional engine and recoilless energy would account for completion of the remaining part of the stroke, the difference to final power output would therefore be negligible.
Valve system in an conventional IC
Engine:-
It would be appropriate before proceeding further , to
examine the effect of the conventional valve system on exhaust
gas velocities and temperature. Conventional poppet type
valves are by design meant to open the exhaust port only
partially and depend upon the pressure created by the movement
of the piston up the cylinder to force the exhaust gases out
through the small gap available . When valve lead takes place
at 50 degrees before BDC during the power stroke of a
conventional engine , the pressure of the exhaust gases on the
piston head is partially released , yet the design of the
exhaust valve is such that much of the heat and therefore
energy of the exhaust gases is lost trying to force their way
past the exhaust valve and the longer time that the exhaust
gases have to stay trapped in the cylinder before the actual
exhaust stroke takes place means that much of the heat in the
exhaust gases is transferred to the engine block thereby
considerably reducing the total energy available when the
gases finally make it out through the exhaust port. The
cam-shaft is designed to fully open the exhaust valve for a
very brief period at BDC , during valve lead ( i.e., exhaust
valve opens 50 degrees before the exhaust stroke) and during
the greater part of the exhaust stroke , the exhaust valve is
only minimally open giving rise to the loss to heat transfer
as discussed above. At the same time this partial release of
gases through the exhaust port results in a greater load being
placed on the fly-wheel since resistance to its movement , and
therefore to the movement of the piston ,is still present in
the form of pressure exerted by partially trapped gases on the
piston head.. While this may have been desirable and even
welcomed at one time , since it results in a cooler exhaust ,
and also results in
better and easier sealing of the
cylinder because of the small distance that the valve has to
travel , it also means that much of the energy available in
the exhaust gases is lost to heat transfer to the engine block
and the rest of it being lost through the exhaust without
being utilised. It is this factor , more than anything else ,
that is central to the relative inefficiency of the present
day RI engine.
By contrast the exhaust valve in the
concept IC engine is activated almost immediately after
ignition, during this very short time , the pressure would
have already peaked in the cylinder, thus the exhaust gases
would be used for powering of the turbine when they have
maximum .energy and velocity , further the reaction produced
by these escaping gases on the piston head would aid in the
transfer of energy to the fly-wheel and the smooth return of
the piston for the next stroke because the pressure of
partially trapped gases on the cylinder head , as exists in
the working of a conventional engine , is absent. In practical
terms it would mean , as has already been explained ,that the
exhaust valve is opened at 80 to 90 degrees before BDC instead
of at 50 degrees as occurs in a conventional engine , thus
conventional power (with valves closed ) would be available
for 80 to 90 degrees of the stroke and recoilless energy for
the remainder of the stroke , one cannot see this making an
appreciable difference to the overall power exerted on the
piston.. The exhaust valve in a concept IC engine is designed
to open as fully as possible and to offer an unrestricted
passage to the exhaust gases. This has the effect of (a)
reducing load on the fly-wheel (b) extracting ,when coupled to
a turbine unit ,the maximum possible energy from the heat
generated by the combustion of fuel.There are more details available on the FAQ page.
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