NOVEL SIMPLER AND EFFICIENT INTERNAL COMBUSTION ENGINE

NOUVEAU MOTEUR A COMBUSTION INTERNE PLUS SIMPLE ET EFFICACE

English Abstract

This invention mainly consists of a geometric novel system that can be mainly
used as 1)
an efficient internally heated combustion engine that can perform a high-
efficient 2-stroke
clean Otto or Diesel cycle 2) a simpler externally heated steam engine with no

boiler requirement 3) an improved stirling engine system operating under two-
phase flow
conditions with high heat transfer rates from the heat source to the working
gas. The new
proposed geometry uses a novel concept system established between piston and
cylinder
that uses incompressible fluid like water as a medium to facilitate the
sealing operation of
the working fluid, gases for internal combustion engine configuration, steam
for the
steam engine or a gas/vapour to the stirling engine. The new sealing system
totally avoids
hot gases/ steam to escape from the cylinder during the combustion and
expansion
processes of the engine thermodynamic cycle. It also can eliminate the need of
special
lubricants in the cylinder walls as typically occurs in convention internal
and external
heated piston engines. This sealing concept allows injection of large amounts
of water
inside the cylinder that can be used in two different ways: a) for internal
combustion
engine configuration the water can be easily injected at the end of the
expansion stroke to
capture sensible heat from the gases producing steam that provides extra
positive work in
the expansion phase; b) for external heated steam engine, the water can be
injected during
the end of the compression phase against a hot surface producing steam
necessary during
the expansion phase. At the beginning of the compression phase water is
injected against
the steam reducing the cylinder pressure and the compression work; c) for the
stirling
engine liquid can be injected in the hot section by the displacer movement
when located
in the cold region.. Another extreme advantage is that for internal combustion
engine
applications, the geometry allows the use of an efficient simple scavenging
pump outside
the engine crankshaft area, allowing excellent scavenging process. This fact
favors low-
emissions production associated with possibility of achieving high amounts of
work per
cycle. Additionally the geometry favours the use of an efficient uniflow type
scavenging
procedure that can also uniquely use valves in both cylinder and piston that
can favor
engine cycle optimization. The possibility of using these valves allows the
engine to




easily perform operations close to Atkinson cycle. Alternatively, as an
external heated
steam engine, the use of valves or not can be adopted, depending on how
complex and
efficient the steam engine system is desired. Both these internal and external
heated
configurations are also very suitable as a cogeneration unit since water can
be directly
heated by the combustion gases and cylinder cooling walls without the need of
complicated heat exchangers. The low-temperature of the sealing components,
the
absence of high-temperature lubrication, the possibility of not having valves
can also
make this design very suitable as a low-maintenance engine that can be used,
as said
above, for residential cogenaration systems or for third-world rural area
power
applications. For the stirling two-phase flow system can solve some of the
problems
associated with stirling engines in terms of the difficulties in transferring
heat from the
outside heat source and the working fluid. A liquid being injected against the
hot surfaces
of the stirling engine parts can easily remove heat and transfer it to the gas
as part of the
working fluid. This can simplify the heat exchanger components of this engine.

Claims

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CLAIMS:


I claim:


1. The use of a liquid (water) as an intermediate medium between the working
fluid
such as exhaust gases inside an engine cylinder and a low-temperature sealing
system
improving sealing effectiveness of internal combustion engines, as shown on
Fig 1.


2. The use of an inverted shape piston that operates in an environment created
by a
cylinder filled with liquid that act an effective sealing mechanism, as shown
on Figs 1
to 6. The inverted piston arrangement allows the liquid from claim 1 to remain

stationary either on fig 1 or 1A.


3. The use of a injection of water against the piston sealing at the end of
every stroke
during the scavenging phase as shown by figure 1A. This water will maintain
the seal
cool so that oil lubrication is not necessary.


4. The use of an scavenge pump that operates on the other side of the piston
described
on claim 2 and that can supply large amounts of air or air-fuel mixtures to
the engine
cylinder, as shown on Fig 1.


5. The use of a liquid medium as described on claim 1, an inverted piston as
described
on claim 2 and an scavenge pump as described on claim 4 that can use an
admission
valve located at the mentioned piston and that allows a uniflow scavenging
process to
occur that is not limited by the movement of the piston as normally occurs
with
cylinder ports, as shown on Fig 1.


6. The use of an engine operating under a two-stroke system using the inverted
piston as
mentioned on claim 2, the liquid sealing mechanism as described on item 1 and
the




-PAGE 23-



scavenge pump as described on claim 4 and that can execute a two-stroke engine

internal combustion cycle with no valves and just inlet and exhaust ports as
shown
on Fig2.

7. The use of an engine operating under a two-stroke system using the inverted
piston
as mentioned on claim 2, the liquid sealing mechanism as described on item I
and the
scavenge pump as described on claim 4 and that can execute a two-stroke engine

internal combustion cycle with a unique inlet valve at the piston and exhaust
valves at
the engine cylinder, as shown by Fig 3.


8. The use of and engine as described on claim 7 with a simple valve control
mechanism
that can be either activated by pressure difference or by the piston movement
as
sketched on Fig 3.


9. The use of an extended expansion concept in an engine as described on claim
7 where
the exhaust valve opens initially by pressure difference and it closes by the
movement
of the piston. The expansion stroke is much longer than the compression stroke
and
the scavenging process can use substantial travel of the initial downward
movement
of the engine. The admission valve, located at the piston, only opens after
the exhaust
valve opening has significantly decrease the engine cylinder pressure
described
above. The admission valve closes by pressure difference from the scavenge
pump
delivery and the engine cylinder. A small spring can also be used with the
admission
valve to make more difficult its opening.


10. The use of an engine with a sealing mechanism as described on item 1, an
inverted
piston as described as claim 2 that uses an admission valve that opens by
pressure
difference induced by the movement of exhaust gases through exhaust ports in
the
two-stroke engine as indicated by Fig 4.


11. The use of the exhaust gases and engine cooling being in direct contact
with water to
heat it directly in a very efficient manner as described on Fig 1. The engine
is based
on engine description on claims 6, 7 and 8.




-PAGE 24-



12. The use of an engine as described on claim 11 and that internally injects
water during
the expansion stroke, removing heat from the exhaust gas and using it to
produce
steam, further increasing the exhaust gas pressure, significantly enhancing
the engine
overall efficiency. This water injection in significant amounts is only
possible due to
the sealing mechanism described on claim 1 and the use of an internal liquid
pump
attached to the movement of the piston as shown of Fig 5.


13. The use of the an engine that uses a sealing mechanism as described on
claim 1, an
inverted piston as described on claim 2 and that uses an internal water pump
to inject
water against a hot spot inside the engine cylinder as shown of Fig5. That
creates
steam internally in an engine that operates with steam as a working fluid and
that
does not require an external boiler, as shown on Fig 6.


14. The use of a sealing mechanism as described on claim 1 and the concept of
steam
generation as mentioned on claim 12 that uses a simple water/ liquid pumping
system
internally to the engine cylinder and that is activated by the piston
movement.


15. The use of a liquid pumping system described on claim 13 and sketched on
Fig 5 that
uses internal circuits in the moving piston to direct to a hot area inside the
engine
being heated externally. The water in contact to this hot area produces steam
necessary to produce pressure inside the cylinder and expand producing useful
work.

The water can be injected under pressure and velocities inside the cavities of
the hot
spot body.


16. The use of a water injection system in the steam engine described on claim
13 and
that can be injected by an internal liquid pumping system as described on
claim 15
into the steam during the compression phase reducing the cylinder engine
pressure
and consequently the negative compression work.





-PAGE 25-



17. The use of an liquid inside a stirling engine sitting on the bottom of the
cold zone that
can be pumped internally by the displacer movement as shown on Fig 7. A small
piston is attached to the displacer mechanism as sketched by the Fig 7 that
can pump
simply and effective inject liquid against the hot surfaces of the engine.


18. The use of the pumping system described on claim 15 and that can be pumped
to the
hot zone by the time the displacer displaces gas to the hot section. A two-
phase flow
system is formed and an enhancement of the heat transfer mechanism from the
heated
walls to the working gas can be executed. Similar condensation mode occurs
once the
liquid looses heat to the cooling engine zone, that reduces engine negative
work. A
sketch is shown on Fig 7.

Description

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Novel Simpler and Efficient Internal Combustion Engine

This invention application as a novel internal combustion engine uses a new
sealing
concept between the piston and cylinder where incompressible fluid is used as
a medium
to seal the engine working gas. Because of that, the engine has several
advantages over
conventional ones: possibility of operating as a clean 2-stroke engine with
extreme high
efficiencies operating close to the Atkinson extended expansion cycle. This
engine is also
very suitable as a cogeneration unit since water can be directly heated by the
combustion
gases without the need of complicated heat exchangers.

BACKGROUND:

Traditionally internal combustion engines use metal rings in the piston to
seal the
combustion gases inside the cylinder. Lubricant oil becomes necessary not only
to
enhance the sealing but also lubricates the ring movement against the cylinder
walls.
With time the oil is partially oxidized and needs to be changed. Specially in
an Otto two-
stroke engine the oil is inevitably burned since the fuel air mixture or just
air for fuel
injection systems is pumped to the cylinder from the lower part of the engine.
So, two-

stroke engines despite of their simplicity burn significant amounts of oil
releasing high
amounts of unburned hydrocarbons to the environment. A conventional four-
stroke burn
much less oil engine minimizing this problem but it has limitations in terms
of extending
the expansion of the combustion gases due to its 4- stroke symmetric travel of
the piston
to effectuate a cycle. The new engine overcomes all these limitations:
1) It can operate in a very clean combustion process as a two-stroke engine
without the
problems of oil burning.


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2) It can perform high-efficient 2-stroke cycles even not using valves due to
the
possibility of having excellent scavenge process due to the possibility of
having good
effective air pumping action.

3) If using valves on both cylinder and piston, in a manner much simpler than
used by
traditional four-stroke engines, it can easily approach an efficient Atkinson
cycle
where an extend expansion of the combustion gases can be executed.

4) It can also be used for cogeneration applications since the exhaust and
engine heat
can be easily transferred to water or another incompressible fluid.

5) The engine cost can be extremely low due to the average low temperature of
the parts
in contact to the combustion gases and the system with no valves can be even
cheaper.

6) The engine can easily use large amounts of water injected at the end of the
expansion
work transforming sensible heat from the exhaust gas into latent heat changing
phase
from water to steam, which produces additional extra work. This can
significantly
increase engine efficiency. Traditional internal combustion engines cannot
inject
water at the expansion phase due to lubrication problems plus the complication
of
having an external water injection system.

7) The engine needs very little maintenance due to the simplicity of the
sealing
mechanism plus the fact that the lubrication oil is not in contact with the
combustion
gases.


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Novel Simpler and Efficient External Heated Engine

This invention application as a novel external combustion engine uses a new
sealing
concept between the piston and cylinder where incompressible fluid is used as
a medium
to seal the engine working gas. Because of that, the engine has several
advantages over
conventional ones: possibility of operating as a externally heated engine.
Steam can be
provided externally by a boiler or in a much simpler proposed configuration,
be generated
inside the cylinder using a hot internal part where water is injected against
it. This engine
is also very suitable as a cogeneration unit since water can be directly
heated by the
exhaust steam without the need of complicated heat exchangers.

BACKGROUND:

Traditionally externally heated steam engines use metal rings in the piston to
seal the
combustion gases inside the cylinder. Lubricant oil becomes necessary not only
to
enhance the sealing but also lubricates the ring movement against the cylinder
walls. In a
conventional steam engine, steam needs to have few condensing water droplets
otherwise
it will create problems on engine efficiency and lubrication. The new engine
overcomes
several traditional internal combustion/ steam engine limitations:

a) It can operate in a very clean externally heated combustion process using
gaseous,
liquid or solid fuel. The continuous combustion process can provide ultra-low
emissions.
b) It can use external heat sources other than burning fuel such as solar
energy or steam
from industrial processes.
c) It can also be used for cogeneration applications since the exhaust steam
and engine
heat can be easily transferred to water or another incompressible fluid.


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- PAGE 7-

d) The engine cost can be extremely low due to the average low temperature of
all
moving parts.

e) A relative easy way of internally producing steam is the use of internal
hot parts inside
the cylinder where water can impinge against it producing steam at the
beginning of the
expansion phase.

f) Water can also be injected as fine spray against the steam, to condense it
at the
beginning of the compression phase, reducing the negative work on the
thermodynamic
cycle. The condensed water will just accumulate with the rest of liquid water
located at
the bottom of the engine cylinder. Water can be injected in a direction
without cooling
much the piston walls. The piston and cylinder walls can also be coated with
composite
materials to reduce heat transfer losses from the working fluid. Traditional
steam engines
have more problems doing this because of the nature of the internal sealing
required from
engine piston rings and cylinder.

Because of these features, the engine has innumerous applications for both
power
generation and heat production:

A) Residential cogeneration that can be used to produce power in residences
that today
burn natural gas for heating purposes only. This will open a new market with
more
than 500 million houses worldwide.

B) Small high efficient generators in a $ 7 billion/ year market requiring
extremely low-
maintenance requirements.

C) It can be used on other applications where size and weight per power
produced is not
so critical.


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PAGE 8-

D) It can use any source of fuel or heat for the externally heated
configuration. This fact
creates great flexibility of operating the engine in rural areas.

E) This is a unique design where there is no requirements to have a boiler
dedicated to
produce steam in the engine. Steam can be quickly produced every cycle
internally
inside the cylinder.

F) Conventional steam engines cannot easily inject water inside the engine
cylinder
because of limitations on efficiency and lubrication on the cylinder walls.
Also a
complicated injection system would be required. The water sealing
configuration
facilitates the use of water from inside the engine cylinder to be pumped
against
either the cylinder hot part (expansion phase) or steam fluid (compression
phase)

G) The injection of water for either expansion or compression phase can be
easily
achieved by the piston movement inside the water, since a simple small pump
system
can be attached to it and used to promote compression of water inside the
cylinder
itself.

n


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- PAGE 9-

SUMMARY OF THE INTERNAL COMBUSTION ENGINE INVENTION:

It is the obiect of the present invention to provide a more efficient, cleaner
and simpler
15 internal combustion engine configuration.
This invention uses a typical engine crankshaft that can use self-lubricating
bearings so
that the lubrication of its components requires very little maintenance. it
does not require
an oil mist around it since the engine piston does not require oil for
lubrication. The
connecting rod is linked to a piston that has an inverted shape so that its
moves inside a
cylinder where there is a liquid, such as water that being incompressible
behaves as an
intermediate medium between the exhaust gases and the sealing system that
prevent this
liquid to escape from the cylinder. The engine can operate with or without
valves. On Fig
1, a scavenging port and an exhaust valve are shown, and the later can be
activated by
pressure differential between the cylinder and the scavenging areas, but on
Fig 2 there is
no valves at all and rather inlet and exhaust ports. On Fig IA an alternative
sealing
system where the rings are located in the internal part of the moving piston,
attached to
the internal fixed cylinder where the exhaust valve is located. This sealing
system
receives a jet of water to cool it down at the moment a port is uncovered by
the piston
movement. Still on both Fig 1 and 2, there is a scavenge pump activated by the
so called
stationary piston located on the other side of the piston. This pump can be as
large as
desire, different than crankcase conventional pumps that have same
displacement as the
engine piston. A larger scavenge pump and the total absence of oil in the
combustion
chamber can provide clean fresh combustion air followed by a much cleaner
combustion
process than those obtained by traditional two-stroke gas engines. Similarly a
fuel pump
or a water pump can be easily incorporated in the other side of the piston as
indicated on

n


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- PAGE 10-

Fig 1. The fuel pump can compress gas fuel and inject it at the beginning of
the
compression phase. A water pump can be used to repose the water lost inside
the
cylinder due to evaporation or leak from the engine piston seals, as shown on
Fig 5.
Another water pump similar to the one shown of Fig 5 can be used to easily
inject water
inside the cylinder at the end of the expansion stroke to use exhaust gases
heat to produce
steam to convert into extra pressure and increase efficiency. Outside the
engine the liquid
level covers the engine cylinder and partially the piston so that engine
rejected heat is in
direct contact w/ water through the piston and exhaust gases (no heat
exchangers).

Following Fig 2, the engine can perform a clean two-stroke cycle with no
valves at all.
The scavenge and exhaust ports are located in the piston that moves and that
is
discovered when surpasses the piston seals. In this case a duct links the air
compressed by
the piston and the stationary cylinder through the piston seals and finally
the cylinder.
Following Fig 3, the use of valves allows the break of the symmetry from the
compression and exhaust phases of the two-stroke cycle, similar to a Miller
cycle
approaching an Atkinson cycle. One advantage at this point is that the 4-
stroke Miller
cycle partially uses twice the movement of the piston around the lower dead
center to
admit and reject some of the incoming air or mixture while in a 2-stroke, this
is only used
once with the addition that during this time the scavenging process is taking
place.
After the ignition and combustion, the gases will expand pushing the piston
upwards. The
exhaust valve controlled by a spring will only open when the engine gas
pressure drops
below a certain value due to the expansion of the exhaust gases. Once it is
open, the
cylinder gas pressure will drop sharply allowing the scavenging valve, also
controlled by
a small spring, to open and inject air pushing more exhaust gas across the
exhaust valve.

1f


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The exhaust valve in this figure is controlled by the movement of the piston
as indicated.
As this exhaust valve opens, it changes the position of small arm of the valve
control
mechanism (see Fig 3) so that when the piston moves downward, it pushes the
valve
down until the cylinder gas pressure completely closes the valve. As the
exhaust valve
opens and the cylinder exhaust gas pressure sharply drops, the admission
scavenging
valve opens through pressure difference and help cleaning the cylinder with
excess of
scavenging air that was pumped by the scavenging pump. The piston starts
moving
downwards and the scavenging valve closes and the exhaust valve starts closing
due to
the valve control mechanism movement. As it closes, fuel can be injected as
indicated by
the fuel compressor that can easily be built in the stationary piston.
Alternatively, a
compression ignition system can be used for a Diesel version of this engine.
At the end
of the compression phase, fuel is well-mixed with the fresh scavenging air and
combustion takes place similar for what occur for either Otto or Diesel
cycles. The
combustion gases expand pushing the piston upwards and now having a longer
expansion
phase than compression. That guarantees high values of efficiency similar to
what
happens to an Atkinson cycle. Fig 4 shows a system with no scavenging pump
where the
cylinder air recharging occurs due to the temporarily cylinder low-pressure
system
created during the cylinder blow down phase. This system uses an air admission
valve
operated by pressure differential from inside and outside the cylinder. In
this case, the
scavenging process is not as effective as the other configurations shown on
Fig 2 and Fig
3, so that the combustion process is not as clean and efficient. However, Fig
4
configuration reflects an engine with fewer moving parts so that cost and
maintenance are
big pluses for this proposed configuration.

1 1


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SUMMARY OF THE EXTERNAL HEATED ENGINE INVENTION:

It is the object of the present invention also to provide a more efficient,
cleaner and
15 simpler external heated engine configuration (Fig 5 and 6). One big
advantage of this
configuration over traditional steam engine configurations is that it does not
need boilers
to produce steam as a working fluid. It rather uses ax extreme simple water
injection
system to generate steam internally to the engine cylinder. This is possible
due to the
sealing system that uses water as the medium that facilitates water injection
and steam
generation internally to the engine. Finally the idea of having liquid present
inside the
cycle can also be applied to Stirling engines: Fig 7 shows an scheme of a
classical free
piston Stirling engine operating with an internal liquid injection system
connected to the
engine displacer. So that at the end of the displacement stroke, water is
injected against
the hot cylinder walls, enhancing heat transfer and therefore increasing cycle
efficiency.
STEAM ENGINE OPERATION- Similarly to the internal combustion engine version,
this configuration uses a typical engine crankshaft that can adopt self-
lubricating
bearings so that the lubrication of its components requires very little
maintenance. It also
does not require an oil mist around it since the engine piston does not
require oil for
lubrication. The connecting rod is linked to a piston that has an inverted
shape so that its
moves inside a cylinder where there could be a liquid, such as water that
being
incompressible behaves as an intermediate medium between the steam and the
sealing
system preventing steam to leak from the cylinder. If there is no liquid
inside the cylinder
(dry mode), than the piston rings are located around the central body
(stationary) of the
cylinder. The engine can operate with and without valves. On Fig 5, the engine
shown
has valves activated by pressure difference (cylinder interior and vapour
pressure inside
injector) and exhaust ports. Similarly a water injection pump can be easily
incorporated
in the other side of the piston as indicated on Fig 5. This pump is actuated
at the end of

In


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- PAGE 13-

the compression phase and injects water against the Hot Spot Cylinder that
receives heat
from any External Heat Source. The Inverted Piston has a central body that is
introduced as the piston moves down against the Hot Spot Cylinder. As the
water is
pumped internally through small ducts inside the Inverted Piston, it is
released against
the Hot Spot Cylinder creating vapour almost immediately. This vapour will
ultimately
increase the cylinder pressure pushing the Inverted Piston upwards during the
expansion
phase. A check valve can be used in the water pump system rod tip. The
internal
generation of steam enormously simplify the steam engine system, eliminating
the need
for a boiler. Similarly, water could also be injected at the beginning of the
compression
phase against the steam volume to reduce compression work. The interior of the
cylinder
can be coated with an insulating material to reduce direct heat transfer from
the steam/
water to the piston, improving steam cycle efficiency.

STIRLING ENGINE OPERATION - Fig 7 shows a classical view of a free piston
stirling
engine: The piston and the displacer connected plus the regenerator. The
insertion of a
simple internal liquid pumping system is the main innovation on this
configuration. At
the position where the displacer is going downwards and the working fluid is
going the
hot section of the engine, liquid is injected against the hot walls changing
phase,
increasing the cylinder pressure and enhancing heat transfer from the hot
walls to the
working fluid. Therefore, heat transfer rates are enhanced and despite the
relative lower
temperatures, less heat losses will guarantee a better efficiency. Also as the
gas/vapour
working fluid moves to the colder engine cycle, a partial condensation of the
vapour
favours heat transfer of the working gas to the cylinder walls.


CA 02731299 2011-02-09

industry Industrie ?,rPJlj
Cenada 'tiUD
Ceneda
2011 /02/09
Application for Letters Patent ININIIIINIINIINI
INIINIIANINIIIINiI
111111111 040 -11
CiPO OPiC E001217096
Novel Heat Engines

Luiz Claudio Vieira Fernandes
Table of Contents

INVENTOR 1
ABSTRACT 2
BACKGROUND - INTERNAL COMBUSTION ENGINE 4
BACKGROUND - EXTERNAL HEATED ENGINE 6
SUMMARY - OF THE INTERNAL COMBUSTION ENGINE 9
SUMMARY - OF THE INTERNAL COMBUSTION ENGINE 12
FIGURES 14
CLAIMS 21


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- PAGE 1-

INVENTOR:

Luiz Claudio Vieira Fernandes

4 Boswell Ave, Toronto, ON, M5R 1 M4 Canada Tel: (647) 981-0956

Representative Drawing