U.S. patent application number 14/130616 was filed with the patent office on 2014-11-20 for method, apparatus, and system for optimizing exhaust backpressure of internal combustion engine.
The applicant listed for this patent is Sigan Peng. Invention is credited to Sigan Peng.
Application Number | 20140338310 14/130616 |
Document ID | / |
Family ID | 47399516 |
Filed Date | 2014-11-20 |
United States Patent
Application |
20140338310 |
Kind Code |
A1 |
Peng; Sigan |
November 20, 2014 |
METHOD, APPARATUS, AND SYSTEM FOR OPTIMIZING EXHAUST BACKPRESSURE
OF INTERNAL COMBUSTION ENGINE
Abstract
A method for optimizing exhaust backpressure of an internal
combustion engine, comprising the following steps: 1) arranging a
damping component in an exhaust passage of the internal combustion
engine, and allowing an exhaust discharged by the internal
combustion engine to pass through the damping component; and 2)
allowing the exhaust to be cooled prior to passing through the
damping component, or allowing the exhaust to be cooled while
passing through the damping component. The method allows for
relatively high exhaust backpressure when the internal combustion
engine has a low load, and for preventing the exhaust pressure from
rising excessively rapid when the internal combustion engine has a
heavy load. The apparatus and system for optimizing exhaust
backpressure of an internal combustion engine is also provided.
Inventors: |
Peng; Sigan; (Wuhan City,
CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Peng; Sigan |
Wuhan City |
|
CN |
|
|
Family ID: |
47399516 |
Appl. No.: |
14/130616 |
Filed: |
September 16, 2011 |
PCT Filed: |
September 16, 2011 |
PCT NO: |
PCT/CN2011/079725 |
371 Date: |
July 9, 2014 |
Current U.S.
Class: |
60/273 ;
60/320 |
Current CPC
Class: |
F01N 3/04 20130101; C02F
1/66 20130101; C02F 1/74 20130101; F01N 1/02 20130101; F01N 13/08
20130101; Y02T 10/16 20130101; Y02T 10/20 20130101; B01D 53/1425
20130101; Y02A 50/2349 20180101; F01N 3/06 20130101; B01D 2252/1035
20130101; F01N 5/02 20130101; C02F 2103/08 20130101; F01N 2260/16
20130101; B01D 2259/4566 20130101; F01N 2570/04 20130101; B01D
53/507 20130101; B01D 53/92 20130101; F01N 2590/10 20130101; F01N
2260/024 20130101; F01N 2260/14 20130101; B01D 2258/01 20130101;
Y02A 50/20 20180101; B01D 53/1481 20130101; B01D 2257/302 20130101;
Y02T 10/12 20130101; B63J 4/006 20130101 |
Class at
Publication: |
60/273 ;
60/320 |
International
Class: |
F01N 13/08 20060101
F01N013/08; F01N 3/04 20060101 F01N003/04 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 1, 2011 |
CN |
201110184097.2 |
Claims
1. A method for optimizing exhaust backpressure of an internal
combustion engine, comprising: 1) providing a damping member in an
exhaust passage of an internal combustion engine, and making
exhaust gas discharged from said internal combustion engine passing
through said damping member; 2) cooling the exhaust gas before
passing through said damping member, or cooling the exhaust gas
while passing through said damping member.
2. A method as claimed in claim 1, wherein said damping member is a
member able to reduce a cross-section of the exhaust passage.
3. A method as claimed in claim 2, wherein said member able to
reduce a cross-section of the exhaust passage is an exhaust pipe
with abruptly reduced cross-sections.
4. A method as claimed in claim 2, wherein said member able to
reduce a cross-section of the exhaust passage is a member having
pores disposed in the exhaust pipe.
5. A method as claimed in claim 1, wherein said damping member is a
member that is able to split the exhaust gas into a plurality of
small tributaries.
6. A method as claimed in claim 1, wherein said damping member is
an exhaust pipe able to change a flow direction of the exhaust
gas.
7. A method as claimed in claim 1, wherein a method of cooling the
exhaust gas is: dividing the exhaust gas into a plurality of small
tributaries, and then making the scattered small tributaries
exchange heat with a cooling medium.
8. A method as claimed in claim 1, wherein a method of cooling the
exhaust gas is: making the exhaust gas and a cooling liquid come
into contact with each other.
9. A method as claimed in claim 1, wherein a method of cooling the
exhaust gas is: making the exhaust gas pass through a member having
a large number of gaps to be divided into a plurality of small
tributaries, and making said small tributaries and a cooling liquid
come into contact in said gaps.
10. A method as claimed in claim 1, wherein said damping member is
located within a housing, and the exhaust gas discharged from an
internal combustion engine is cooled within the housing, wherein
said method further comprises: making the exhaust gas discharged
from the internal combustion engine enter into an interior of said
housing through a exhaust gas inlet of said housing, and then
making the cooled exhaust gas discharge out of said housing through
a exhaust gas outlet of said housing.
11. A method as claimed in claim 10, wherein an abrupt expansion of
cross-sections is formed from said exhaust gas inlet to the
interior of said housing.
12. A method as claimed in claim 11, wherein the cross-section area
of said exhaust gas inlet is 0.05 to 0.5 times the cross-sectional
area of said housing.
13. A method as claimed in claim 1, wherein a method of cooling the
exhaust gas is: making the exhaust gas and a cooling liquid come
into contact with each other in an interior of a housing, wherein
said method further comprises: making the cooling liquid enter into
an interior of the housing through a cooling water inlet of said
housing, and discharging the cooling liquid having absorbed heat of
the exhaust gas from the housing through a cooling water outlet of
said housing.
14. A method as claimed in claim 13, wherein said cooling liquid is
cooling water in natural water body, wherein said method further
comprises: extracting cooling water from natural water body and
conveying it to said housing.
15. A method as claimed in claim 13, wherein said cooling liquid is
cooling water of an internal combustion engine, wherein said method
further comprises: conveying cooling water of an internal
combustion engine to said housing.
16. A method as claimed in claim 13, wherein said method further
comprises: conveying the cooling liquid having absorbed heat of the
exhaust gas to a heat utilization apparatus or a heat
exchanger.
17. A method as claimed in claim 1, wherein said method further
comprises: the exhaust gas discharged from an internal combustion
engine flowing through impellers of a turbocharger working prior to
entering said housing.
18. An apparatus for optimizing exhaust backpressure of an internal
combustion engine, comprising: 1) a housing; 2) a exhaust gas inlet
provided on the housing allowing a exhaust gas to enter into an
interior of the housing, a exhaust gas outlet provided thereon
allowing a exhaust gas to be discharged out of the housing; 3) a
damping member provided in the interior of the housing or on the
housing; 4) a cooling member provided in the interior of the
housing for cooling a exhaust gas.
19. An apparatus as claimed in claim 18, wherein an abrupt
expansion of cross-sections is formed from said exhaust gas inlet
to the interior of said housing.
20. An apparatus as claimed in claim 19, wherein the cross-section
area of said exhaust gas inlet is 0.05 to 0.5 times the
cross-sectional area of said housing.
21. An apparatus as claimed in claim 18, wherein said damping
member is a padding layer of paddings filled in said housing with
gaps therebetween.
22. An apparatus for optimizing exhaust backpressure of an internal
combustion engine, comprising: 1) a housing; 2) a exhaust gas inlet
provided on the housing allowing a exhaust gas to enter into an
interior of the housing, a exhaust gas outlet provided thereon
allowing a exhaust gas to be discharged out of the housing; 3) a
damping member provided in an interior of the housing or on the
housing; 4) a cooling water inlet provided on the housing allowing
cooling water to enter into the housing, a cooling water outlet
provided thereon allowing cooling water to be discharged out of the
housing; said cooling water inlet, cooling water outlet, exhaust
gas inlet and exhaust gas outlet configured so that cooling water
and exhaust gas able to come in to contact with each other in an
interior of the housing.
23. A system for optimizing exhaust backpressure of an internal
combustion engine, comprising an exhaust passage of an internal
combustion engine, wherein said system further comprises an
apparatus for optimizing exhaust backpressure of an internal
combustion engine as claimed in claim 22, which is mounted in said
exhaust passage of an internal combustion engine.
24. A system as claimed in claim 23, further comprising an
apparatus for allowing exhaust gas emission to generate pressure
drop, mounted in said exhaust passage of an internal combustion
engine, and located downstream of said apparatus for optimizing
exhaust backpressure of an internal combustion engine.
25. A system as claimed in claim 23, further comprising: an
apparatus able to extract cooling water from natural water, and
convey it to said housing.
26. A system as claimed in claim 23, further comprising: an
apparatus able to convey cooling water of an internal combustion
engine to said housing.
27. A system as claimed in claim 23, further comprising a heat
utilization apparatus or heat exchanger, and a pipe able to convey
fluid from said housing to said heat utilization apparatus or heat
exchanger.
28. A system as claimed in claim 23, further comprising a
turbocharger, said exhaust passage of an internal combustion engine
is a exhaust gas passage connected to an exhaust port at the
exhaust gas side of said turbocharger.
29. A method for muffling exhaust gas of an internal combustion
engine, comprising: discharging a high-temperature exhaust gas from
an internal combustion engine entering into an interior of a
housing through a exhaust gas inlet on the housing, and further
comprising: allowing the high-temperature exhaust gas entering into
an interior of the housing and a cooling liquid come into contact
with each other.
Description
FIELD OF THE INVENTION
[0001] The present invention pertains to the technical field of
efficiency enhancing of an internal combustion engine, and relates
to a method for optimizing exhaust backpressure of an internal
combustion engine. The present invention further relates to an
apparatus and system for optimizing exhaust backpressure of an
internal combustion engine.
DESCRIPTION OF THE PRIOR ART
[0002] In this century, the world's oil resources insufficiency and
environmental pollution problems have become increasingly
prominent, and there is the need to further improve the economy of
the internal combustion engine and exhaust cleaning. The energy
efficiency of the internal combustion engine, i.e. fuel efficiency
also needs to be further improved, which is the basis and
prerequisite of all facilities and equipment powered by internal
combustion engines to enhance energy efficiency.
[0003] At present, the main way to increase the energy efficiency
of internal combustion engine is to improve the ventilation effect,
i.e. intake and exhaust process, of the internal combustion engine.
The way of improving intake is `pressure boost`, i.e. to increase
the intake pressure; the way of improving exhaust is
`depressurization`, i.e. to reduce the exhaust backpressure, that
is, to reduce the resistance of the exhaust. `Pressure boost` and
`depressurization`, the two complement each other.
[0004] The pressure boost technology developed at the beginning of
last century dramatically improves the performances of the power,
economy and emission of the internal combustion engine, which has
become an important symbol of the internal combustion engine
development. Pressure boost model has become the basic model of the
internal combustion engine, and in particular, the turbine pressure
boost technology that uses the internal combustion engine exhaust
gas to drive a turbine, and then a compressor is driven by a
turbine to `pressure boost` intake air of an internal combustion
engine, and the intercooling technology that is combined with
intake air pressure boost, have now developed into a near-perfect
and are widely used. But the disadvantage is: the acceleration
performance of the internal combustion engine is limited due to the
internal combustion engine being sensitive to exhaust
backpressure.
[0005] The so-called `depressurization` is to reduce the exhaust
backpressure, and the exhaust backpressure is related to the
exhaust resistance of the internal combustion engine. With the
increase of the load when the engine operates, the mass of the
exhaust gas and the temperature of the exhaust gas are also
increased. With the double impact of the mass and temperature of
the exhaust gas, the volume flow and the flow rate of the exhaust
increase even larger, so that the resistance of the exhaust
passage, including the resistance of the other components (e.g., a
muffler) in the exhaust passage, rises rapidly due to the law of
positive pressure being proportional to the square of flow rate.
Therefore, the internal combustion engine backpressure also
increases rapidly with the engine load. High backpressure means
that the exhaust gas flow is encountered with a large resistance,
such that the exhaust within the cylinder is difficult to discharge
cleanly, thus affecting subsequent combustion quality. Therefore,
the exhaust backpressure affects the performance of an internal
combustion engine. The increase of the backpressure will lead to
decrease of the combustion efficiency, economy and emission
performance of the internal combustion engine, and in the meantime
the power performance decreases and fuel consumption increases.
Data shows that this will cause at least more than 10% loss of
energy efficiency to the internal combustion engine. Especially for
a turbocharged internal combustion engine rotating at high speed
relying on an exhaust gas driven turbine, the increase of the
exhaust backpressure leads to a decrease of the pressure drop of
the exhaust gas which drives the turbine, causing a decrease of the
effect of turbocharging, which in turn makes the intake pressure
reduced, so as to result in a further decrease of the energy
efficiency of the internal combustion engine. What is even more
serious is that, with countries being increasingly strict on
international environmental regulations, the requirements for the
internal combustion engine exhaust gas treatment are also
increasingly higher.
[0006] As the backpressure of a system is the sum of the pressure
drops formed by the airflow sequentially passes through each of the
elements in the system, and the pressure drop formed by passing
through each element is proportional to the square of the flow rate
of the airflow passing through. Accordingly, after the installation
of the exhaust processing devices and apparatus for muffling,
purification or even waste heat recovery for an internal combustion
engine, the engine exhaust backpressure is greatly increased, the
energy efficiency of an internal combustion engine is reduced, and
energy consumption is increased. The rise of the internal
combustion engine energy consumption means more fossil fuel
consumption, resulting in more pollution, which in turn results in
reducing the effects of the environmental protection and
energy-saving measures taken earlier.
[0007] So, while people are continuously developing the `pressure
boost` technology, they are also seeking for technology of
`depressurization`, such as the multi-valve technology which
enlarges the exhaust gas flow space by using multiple exhaust
valves, so that the exhaust backpressure is reduced. For some
special competitive occasions, such as racing, the power of an
internal combustion engine is required to give full play, even
without installing a muffler aiming to reduce backpressure as much
as possible.
[0008] However, in a situation where the internal combustion engine
is under low load, if the exhaust backpressure is very low, due to
the exhaust valve being opened in advance, the fuel gas still
having certain pressure will be discharged from the excessively
clear exhaust valve before the piston reaches the bottom stop
point, such that a portion of power is lost and the torque is
reduced. It can be seen that keeping up a certain exhaust
backpressure when the internal combustion engine is under low load
will instead increase the torque.
[0009] In summary, for the backpressure of an internal combustion
engine, it is desired that the backpressure is not too low when the
internal combustion engine is under low load, and however, it is
desired that the exhaust backpressure is restrained to the greatest
extent from increasing too rapidly. Only then the efficiency
improvement of the internal combustion engine can only be realized
under all working conditions thereof
SUMMARY OF THE INVENTION
[0010] In view of the existing desires for the exhaust backpressure
of an internal combustion engine, the present invention provides a
new method, a new apparatus and a new system for optimizing exhaust
backpressure of an internal combustion engine. The present
invention is based upon the principle: If the exhaust gas of an
internal combustion engine is rapidly cooled, the exhaust
backpressure can be greatly reduced. So, when the internal
combustion engine is under low load, a certain amount of exhaust
resistance is arranged such that the backpressure will not go so
far as to be too low; when the internal combustion engine is under
high load, the exhaust gas is rapidly cooled so that the
backpressure will not go so far as to rise too rapidly.
[0011] A first object of the present invention is to provide a
method for optimizing exhaust backpressure of an internal
combustion engine, comprising: [0012] 1) providing a damping member
in an exhaust passage of an internal combustion engine, and making
an exhaust gas discharged from an internal combustion engine
passing through said damping member; [0013] 2) cooling the exhaust
gas before passing through said damping member, or cooling the
exhaust gas while passing through said damping member.
[0014] By utilizing the method provided by the present invention
the following can be achieved: a relatively higher exhaust
backpressure when the internal combustion engine is under low load,
and the exhaust backpressure will not rise too fast when the
internal combustion engine is under high load. Specifically,
allowing the exhaust gas discharged by the internal combustion
engine to pass through a damping member that is capable of
providing a certain amount of exhaust resistance produces a desired
relatively high exhaust backpressure, so as to increase the torque
of the internal combustion engine when it is under low load. The
exhaust gas being rapidly cooled before or when it passes through
the damping member can achieve the purpose of increasing gas
density of the exhaust gas and decreasing the flow rate of the
exhaust gas. The backpressure is restrained from rising to fast
when the internal combustion engine is under intermediate, high
load, so as to improve the efficiency of the internal combustion
engine.
[0015] The present invention also provides an apparatus for
optimizing exhaust backpressure of an internal combustion engine,
comprising: [0016] 1) a housing; [0017] 2) an exhaust gas inlet
provided on the housing allowing an exhaust gas to enter into an
interior of the housing, an exhaust gas outlet provided thereon
allowing an exhaust gas to be discharged out of the housing; [0018]
3) a damping member provided in the interior of the housing or on
the housing; [0019] 4) a cooling member provided in the interior of
the housing for cooling an exhaust gas.
[0020] Based on the above principle, mounting the apparatus
provided by the present invention in the exhaust passage can not
only provide a certain amount of exhaust resistance when the
internal combustion engine is under low load, but also makes the
exhaust backpressure not rise too fast when the internal combustion
engine is under high load. Especially when the existing members
having resistance, such as mufflers, in the exhaust passage is
replaced with the apparatus of the present invention, the overall
performance of the exhaust system can be preferably improved.
[0021] The present invention also provides another apparatus for
optimizing exhaust backpressure of an internal combustion engine,
comprising: [0022] 1) a housing; [0023] 2) an exhaust gas inlet
provided on the housing allowing an exhaust gas to enter into an
interior of the housing, an exhaust gas outlet provided thereon
allowing a exhaust gas to be discharged out of the housing; [0024]
3) a damping member provided in the interior of the housing or on
the housing; [0025] 4) a cooling water inlet provided on the
housing allowing cooling water to enter into the housing, a cooling
water outlet provided thereon allowing cooling water to be
discharged out of the housing; [0026] said cooling water inlet,
cooling water outlet, exhaust gas inlet and exhaust gas outlet
configured so that cooling water and exhaust gas able to come in to
contact with each other in an interior of the housing.
[0027] Similarly, installing the apparatus in the exhaust passage
can also achieve the purpose of optimizing exhaust backpressure of
an internal combustion engine.
[0028] The present invention also provides a system for optimizing
exhaust backpressure of an internal combustion engine, comprising
an exhaust passage of an internal combustion engine, wherein said
system further comprises an apparatus for optimizing exhaust
backpressure of an internal combustion engine provided by the
present invention, which is mounted in said exhaust passage of an
internal combustion engine. Based on the same principle, the
present invention provides a system that can achieve the purpose of
optimizing exhaust backpressure of an internal combustion
engine.
[0029] Utilizing the method, apparatus and system provided by the
present invention can simply and efficiently enhance the power of
an internal combustion engine, reduce fuel consumption and enhance
the specific power of an internal combustion engine, and can be
applied to various devices using internal combustion engine as the
power.
[0030] The first principle of the present invention is: set a
certain amount of exhaust resistance, so that an internal
combustion engine has a desired, relatively high exhaust
backpressure when under low load.
[0031] The scheme to achieve its purpose is: to provide a damping
member in the exhaust passage of an internal combustion engine, and
allow the exhaust gas discharged from the internal combustion
engine to pass through said damping member.
[0032] Here, the damping member is a member that can provide a
certain amount of exhaust resistance, that is, the pressure drop
produced before and after exhaust gas passing through the damping
member is a desired pressure drop. Forms of the damping member may
include: 1) reducing the cross-section of the exhaust passage of
the internal combustion engine, or 2) dividing the exhaust gas into
small tributaries, or 3) changing the flow direction of the exhaust
gas, or 4) other forms that can provide a certain amount of exhaust
resistance, or 5) a combination of the above forms.
[0033] The damping member is a member that can reduce the
cross-section of the exhaust passage, such as an exhaust pipe with
abruptly reduced cross-sections, or a member provided in the
exhaust pipe and having pores. It can be provided to abruptly
reduce the cross-section of the exhaust passage of an internal
combustion engine, so as to provide a certain amount of exhaust
resistance. Such as, providing a baffle with pore in the exhaust
pipe of an internal combustion engine, such that the exhaust gas
can only pass through the pores. It also can be provided such that
the exhaust pipe of an internal combustion engine abruptly becomes
thinner. In addition, the larger the extent to which the
cross-section reduces, the larger the exhaust resistance.
[0034] The damping member may also be a member that can divide the
exhaust gas into a plurality of tributaries. Here, the way of the
noted `divide the exhaust gas into a plurality of tributaries` may
be making the exhaust gas pass through a structure with a plurality
of distributed pores, and the exhaust gas is thus dispersed by the
pores. The way used may also be making the exhaust gas pass through
a structure with a plurality of gaps, and the exhaust gas is thus
dispersed by the gaps. By the method of dividing the exhaust gas
into small tributaries, a certain amount of exhaust resistance can
also be provided. In the method, the degree of the exhaust gas
being divided can be adjusted depending on the desired exhaust
backpressure: the more the number of small tributaries into which
the exhaust gas is divided, the thinner the divided small
tributaries, and the greater the exhaust resistance; vice
versa.
[0035] The damping member may also be an exhaust pipe that can
change the flow direction of the exhaust gas. A certain amount of
exhaust resistance can also be provided if the flow direction of
the exhaust gas is changed, such as by having a plurality of curved
exhaust pipes.
[0036] The damping member referred to in the present invention can
also be provided in the interior of a housing, and cools the
exhaust gas discharged by the internal combustion engine in the
interior of the housing. So, the method provided by the present
invention can also include: making the exhaust gas discharged by
the internal combustion engine enter into the interior of the
housing through an exhaust gas inlet on the housing, then discharge
the cooled exhaust gas out of the housing through an exhaust gas
outlet on the housing. The damping member may be located in the
interior of the housing, such as by providing a pore plate or
padding with a large number of gaps in the interior of the housing.
In addition, the damping member may also be located on the housing,
such as an abrupt reducing of cross-sections existing from the
interior of the housing to the exhaust gas outlet on the
housing.
[0037] Another principle of the present invention is: the
high-temperature exhaust gas of an internal combustion engine being
rapidly cooled may greatly reduce the flow rate of the exhaust gas,
so that the exhaust backpressure will not rise too fast when the
internal combustion engine is under high load.
[0038] It is known in the prior art that: the existing structure of
the exhaust passage of the internal combustion engine having a
certain amount of exhaust resistance (e.g., an exhaust pipe,
muffler, etc.), as the load of the internal combustion engine
increases, the gas displacement and the exhaust temperature will
rise with it, so that the flow rate rises, and due to the positive
pressure, i.e. the resistance being proportional to the square of
the flow rate, the exhaust backpressure is thus caused to rise
rapidly.
[0039] The applicant has found that before or when the exhaust gas
is encountered with a certain amount of resistance, the exhaust
backpressure may be reduced if the exhaust gas temperature can be
rapidly lowered, thereby improving the efficiency of the internal
combustion engine.
[0040] The scheme of rapidly reducing the temperature of the
exhaust gas may be: 1) making the exhaust gas and the cooling
liquid come into contact with each other; or 2) dividing the
exhaust gas into a plurality of small tributaries, and then making
the dispersed small tributaries heat exchange with the cooling
medium, or 3) a combination of the above two.
[0041] If the high-temperature exhaust gas is made to come into
direct contact with a cooling liquid such as cooling water, the
purpose of rapid cooling can be achieved. A preferable way is to
keep the cooling water flowing, such as the use of spray,
discharging the cooling water which has absorbed heat, and the
exhaust gas continuously contacting the new cooling water, thus the
cooling effect will be better.
[0042] Here, the cooling water source can be determined based on
the specific circumstances.
[0043] The cooling water used as the cooling fluid may come from an
external independent water system of the immediate natural
environment, for example, taken from the natural water body such as
seawater or inland freshwater naturally existing. As to the
apparatus (such as vessels) that use the internal combustion engine
as the power on the ocean or freshwater, the cooling water may be
directly extracted from the seawater or freshwater of the immediate
nature environment, or, the seawater or freshwater may be firstly
stored in a water storing apparatus such as water tank, water
tower, the cooling water is obtained from the water storing
apparatus. The cooling water which has absorbed heat may be
directly discharged to the immediate natural environment; also the
cooling water which has absorbed heat may be processed before being
discharged to the immediate natural environment. Thus, the method
provided by the present invention also includes: extracting cooling
water from a natural water body and convey it to the housing. The
system provided by the present invention also includes an
apparatus, such as a cooling water intake pipe installed with a
pump, which is able to extract cooling water from a natural water
body and convey it to the housing, the cooling water intake pipe
communicating with the cooling water inlet of the housing.
[0044] The cooling water of the internal combustion engine may also
be reused to be used as the cooling water for cooling the liquid.
Most apparatus that uses internal combustion engine as the power,
such as vehicles, vessels, etc., per se, have a set of cooling
water system of internal combustion engine. In this case, the
cooling water may be taken from the cooling water system of the
power apparatus itself. Therefore, the method provided by the
present invention also includes conveying the cooling water of an
internal combustion engine to a housing. The system provided by the
present invention also includes an apparatus that is able to convey
the cooling water of an internal combustion engine to a
housing.
[0045] The cooling water used as the cooling liquid may be used
combining the above two methods, both using the cooling water from
a natural water body and using the cooling water of the internal
combustion engine.
[0046] The cooling water used as the cooling liquid may also be
recycled. The cooling water discharged from the housing, which has
absorbed heat of the high-temperature exhaust gas, may be directly
discharge out or discharged after being processed, and may also be
recycled. For example, the cooling water absorbing heat after
cooling the high-temperature exhaust gas may flow through a heat
exchanger, being cooled before entering the housing again as the
cooling water.
[0047] The cooling water may be allowed to come into contact with
the exhaust gas of an internal combustion engine in an interior of
a housing, thereby achieving the purpose of rapidly reducing the
temperature of the exhaust gas. Therefore, the method provided by
the present invention may also include: making the cooling liquid
enter into the interior of the housing through the cooling water
inlet of the housing, and discharging the cooling liquid which has
absorbed heat from the exhaust gas out of the housing through the
cooling water outlet of the housing.
[0048] The exhaust gas of the internal combustion engine may be
allowed to enter from the exhaust gas inlet on a housing, and be
discharged from the exhaust gas outlet, forming an exhaust gas flow
path. In addition, the cooling water may be allowed to enter from
the cooling water inlet of the housing, and be discharged from the
cooling water outlet, forming a cooling water flow path. The
exhaust gas inlet abovementioned refers to any opening that allows
fluid enter into the interior of the housing, which may be a direct
opening on the wall of the housing, then, through a connecting
member, communicates with the pipe for conveying liquid. The
housing may also be integrally molded with the conveying pipe. The
conveying pipe may also extend into the interior of the housing, so
that, the exhaust gas inlet refers to the pipe orifice extending
into the interior of the housing. The cooling water inlet, cooling
water outlet and the exhaust gas outlet may also use the various
forms as abovementioned.
[0049] The housing used by the present invention is a closed
housing, that is, except the positions of abovementioned exhaust
gas inlet, exhaust gas outlet, cooling water inlet, cooling water
outlet, the other parts are all sealed, and the gas or liquid
entering the housing can only enter and exit from the
abovementioned inlets and outlets.
[0050] In order to achieve the purpose of rapid cooling of the
exhaust gas, in the method and apparatus provided by the present
invention, the exhaust gas of an internal combustion engine and the
cooling water are required to come into contact with each other,
that is, the flow path of the exhaust gas of the internal
combustion engine and the flow path of the cooling water are made
to overlap with each other.
[0051] If a more optimal cooling effect is desired, one preferred
embodiment is to make the exhaust gas of the internal combustion
engine and the cooling water to contact reversely or/and laterally,
that is, the flow direction of the exhaust gas and the flow
direction of the cooling water are away from each other or facing
each other, or nearly away from each other or facing each other. If
the cooling water inlet is made to be located downstream of the
exhaust gas flow, and the cooling water outlet is located upstream
of the exhaust gas flow, the cooling water and exhaust gas thereby
may reversely contact, such that the contact is more adequate.
Therefore, in a preferred embodiment, the exhaust gas of the
internal combustion engine and the cooling water reversely contact.
In a more preferred embodiment, the exhaust gas of the internal
combustion engine pass through the interior of the housing from
bottom to top, and the cooling water pass through the interior of
the housing from top to bottom, allowing them to reversely contact.
The advantage thereof is that the exhaust gas of the internal
combustion engine may disperse in the interior of the housing more
adequately, and the cooling water may flow by fully utilizing the
gravity effect, other than applying extra pressure to maintain its
flowing. Thus, the cooling water inlet may be configured to be
higher than the cooling water outlet in the gravity direction, so
that the cooling water entering the housing through the cooling
water inlet passes through the interior of the housing from top to
bottom; the exhaust gas inlet is lower than the exhaust gas outlet
in the gravity direction, so that the exhaust gas entering the
housing through the exhaust gas inlet passes through the interior
of the housing from bottom to top. Thus, the cooling water and the
exhaust gas may reversely contact, thereby the contact is more
adequate.
[0052] In order to further enhance the full contact of the cooling
water and the exhaust gas, one can think of ways to improve the
degree of dispersion of the cooling water entering the housing. For
instance, one or more water distributor composed of spraying member
with a plurality of pores, arranged uniformly on the upper side of
the interior of the housing, spraying the cooling water onto the
entire interior of the housing to the best of it, so that the
cross-section of the housing can be uniformly distributed with
water. Thus, the method provided by the present invention also
includes: dispersing the cooling water entering the interior of the
housing. The housing of the apparatus provided by the present
invention is also provided with a member dispersing the cooling
water entering into the interior of the housing, such as a water
distributor.
[0053] In a more preferred embodiment, in order to not allow the
cooling water from entering the exhaust pipe of the internal
combustion engine from the exhaust gas inlet, the cooling water
outlet may be configured to be lower than the exhaust gas inlet in
the gravity direction. Thus, before the liquid surface of the
cooling water flowing to or falling onto the bottom of the housing
reaches the position of the exhaust gas inlet, the cooling water is
already discharged from the cooling water outlet.
[0054] In addition, the bottom of the casing may also be provided
with a water seal, making the liquid surface of the cooling water
higher than the cooling water outlet and lower than the exhaust gas
inlet. Thus, the exhaust gas will not flow out from the cooling
water outlet. Further, providing a water seal makes the cooling
water not enter the exhaust gas inlet, even if the angle of
inclination of the water seal liquid surface in all direction
reaches 22.5 .degree..
[0055] In a more preferred embodiment, the exhaust gas inlet is
located on the lower portion of the side surface of the housing,
and the exhaust gas outlet is located at the top of the housing,
and the exhaust gas outlet may connect directly to the chimney,
discharging directly the exhaust gas into the atmosphere. The
cooling water inlet is located on the upper portion of the side
surface of the housing, and the cooling water outlet is located on
the lower portion of the side surface. Moreover, in the gravity
direction, the cooling water outlet is lower than the exhaust gas
inlet. In a most preferred embodiment, the exhaust gas inlet is
located at the bottom of the housing, and the exhaust gas outlet is
located at the top of the housing, so that the exhaust gas inlet
may connect directly to the exhaust pipe of the internal combustion
engine, and the exhaust gas outlet connects directly to the
chimney, discharging the exhaust gas directly into the
atmosphere.
[0056] If the exhaust gas is divided into small tributaries, and
then the dispersed small tributaries heat exchange with a cooling
medium, so that the efficiency of heat exchange between the exhaust
gas and the cooling medium can be greatly improved, thereby
achieving the purpose of rapidly reducing the exhaust temperature,
so that the exhaust backpressure will not rise too face when the
internal combustion engine is under high load. Another effect of
cooling the exhaust gas in this way is: such that the exhaust
backpressure will not be too low when the internal combustion
engine is under low load, thereby achieving the effect of
optimizing the exhaust backpressure under all working
conditions.
[0057] Here, the way of the abovementioned `dividing the exhaust
gas into small tributaries` may be making the exhaust gas pass
through a structure with pores distributed therein, and the exhaust
gas is thus dispersed by the pores. The way used may also be making
the exhaust gas pass through a structure having gaps, such as a
heat dissipating sheet, and the exhaust gas is thus dissipated by
gaps.
[0058] Here, the cooling medium may be gases having endothermic
properties, such as air, hydrogen, etc. Then the cooling medium may
be made to come into contact with the exhaust gas, which is divided
into small tributaries, through the cooling member, so that the
exhaust gas is cooled. The cooling member may be a heat dissipating
sheet or radiator made of materials having good heat transfer
properties, such as a metal material. A part of the cooling member
is located in the housing, and a part outside the housing, being
able to rapidly transfer the heat of the exhaust gas in the housing
to the outside of the housing to be released. In this case, the
process of heat exchange between the exhaust gas and the cooling
member is at the same time the process of the exhaust gas being
divided into small tributaries. Here, the cooling medium may also
be in the form of a combination of cooling member and fluid, such
as the flowing cooling water being encapsulated in a metal pipe,
which can also achieve the purpose of rapid cooling. The benefit of
doing so is that the cooling water in the pipe may generate vapor,
the heat of which may be conveniently and directly utilized. For
example, heat exchange is performed between a heat exchanger of
tubular, plate, tube-wall or finned tube, and the exhaust gas.
Similarly, when the high-temperature exhaust gas passes through the
heat exchanger, it is divided into small tributaries to then
perform heat exchange with the heat exchanger as well.
[0059] As described above, when the internal combustion engine is
under high load, the backpressure is desired to be as low as
possible. While in the prior art, the exhaust resistance of the
structure (such as a muffler) provided in the exhaust passage of
the internal combustion engine is relatively small. Therefore, in
the case of the internal combustion engine being under low load,
the desired exhaust backpressure cannot be achieved. In this way,
the process of dividing the exhaust gas into small tributaries is
also the process of providing a certain amount of exhaust
resistance. The degree of the exhaust gas being divided can be
adjusted depending on the desired exhaust backpressure. The more
the small tributaries of the exhaust gas divided, the thinner the
small tributaries divided, the greater the exhaust resistance; vice
versa.
[0060] Accordingly, in this way, the purpose of optimizing exhaust
backpressure of an internal combustion engine under all working
conditions can be realized.
[0061] For the cooling of the exhaust gas, the most preferred way
is to divide the exhaust gas into small tributaries, which is then
cooled by way of making which and the cooling liquid (such as
cooling water) come into contact with each other. For example, the
exhaust gas is made to pass through a member having a large amount
of gaps, to be divided into a plurality of small tributaries which
in said gaps come into contact with the cooling liquid. In a
preferred embodiment of the present invention, the housing is
filled with padding which form gaps thereinbetween, thereby forming
a padding layer having a large number of gaps which is a member
which can divide the exhaust gas into a plurality of small
tributaries, i.e. the damping member. Padding containing gaps
thereby having a large specific surface area may be included in the
housing, for the purpose that a large number of pores are formed in
at least a part of the space inside the housing. Thus, the cooling
fluid has to be dispersed when passing through the pores between
the padding, in which the cooling fluid and the exhaust gas may
fully contact. When the cooling liquid is cooling water, the form
of padding may be selected to be the common bulk padding as Pall
rings, Raschig rings or other saddle rings, also may be selected to
be a common structured padding. The padding texture is preferred to
be weatherproof materials like metal, ceramics, etc., and also can
be selected to be polymer materials, such as polypropylene,
polyethylene, or ABS engineering plastics, etc., or there kinds of
materials may be used in combination. The high-temperature exhaust
gas is divided into small tributaries when passing through this
padding having a large specific surface area, preferably making the
cooling liquid like cooling water come into direct contact with the
high-temperature exhaust gas in said padding, allowing the
high-temperature exhaust gas to be cooling rapidly. Therefore, in
the method and apparatus provided by the present invention, the
housing is filled with padding which can form gaps thereinbetween,
forming a padding layer with a large number of gaps. The method
provided by the present invention also includes: the exhaust gas is
made to pass through a padding layer having a large number of
gaps.
[0062] In addition, if the cooling fluid is selected to be cooling
gas, such as air, the purpose of rapid cooling may also be
achieved. In this case, the padding is preferably selected to be
ceramic, enamel and metal materials, and these kinds of materials
may be used in combination.
[0063] The method or apparatus provided by the present invention is
specially suited for a turbocharged internal combustion engine,
where the exhaust gas discharged by the internal combustion engine
passes through a turbocharger impeller and works, before entering
the housing from the gas inlet of the housing. Accordingly, the
method provided by the present invention also includes: the exhaust
gas discharged by the internal combustion engine passes through the
turbocharger impeller and works before entering the housing. The
exhaust passage of the internal combustion engine of the system
provided by the present invention may be an exhaust passage of
high-temperature exhaust gas, which is connected to the exhaust
outlet at the exhaust gas side of the turbocharger.
[0064] Further, as the exhaust passage of current internal
combustion engine is normally provided with one or more of a
muffler, exhaust gas purification and waste heat recycling
apparatus or devices. If these apparatus are arranged in the
exhaust passage of the internal combustion engine, a certain amount
of exhaust resistance will be provided, providing pressure drop in
the exhaust path of the exhaust gas, and these apparatus are the
apparatus that can make exhaust gas discharge produce a pressure
drop. The more the pressure drop is, the greater the exhaust
resistance is, leading to a higher exhaust backpressure.
[0065] According to the apparatus or devices through which the
exhaust gas of the internal combustion engine passes before
eventually discharged into the atmosphere, and to the different
order of passing through these apparatus or devices, the method of
the present invention has at least the following several
applications: that is, the present method is applied before or
after the exhaust gas passing through the above apparatus or
devices, or the apparatus for optimizing backpressure according to
the present invention is made to achieve the functions of the above
apparatus or devices at the same time of optimizing backpressure,
so as to replace the above apparatus or devices.
[0066] Thus, the system provided by the present invention may
possibly has several ways described as follows, wherein, for
convenience of description, in the following content, P.sub.0 is
set to be the external atmospheric pressure. In addition, the
pressure drop caused by the resistance of the exhaust pipe is
ignored, and pressure drop .DELTA.P is used to represent the local
pressure drops of one or more other exhaust gas treatment apparatus
and devices. As the gas flow passes through the damping member is
the apparatus of the present invention, the cooling apparatus per
se will bring in a pressure drop .DELTA.P.sub.i. Here it should be
noted that, when the load of the internal combustion engine rises,
the flow rate were to be increased rapidly, but due to the
high-temperature exhaust gas being cooled rapidly with increased
density and decreased volume, the flow rate thereby is lowered
rapidly. Thus, in the case of a relative high-temperature exhaust,
the rising range of .DELTA.P.sub.i is small when the load of the
internal combustion engine is increasing. In this case, as the flow
rate is an exponential relationship with the positive pressure, the
positive pressure or resistance caused by the decrease of the flow
rate is still decreasing, even taking into consideration of the
factor of the increase brought to the positive pressure by the
increase of the exhaust gas density.
[0067] When there is no other exhaust gas treatment apparatus and
device in the exhaust pipe, the exhaust backpressure of the
internal combustion engine then is approximately to be the sum of
the external atmospheric pressure P.sub.0 and the pressure drop
.DELTA.P.sub.i of the cooling apparatus per se, i.e.:
P=P.sub.0+.DELTA.P.sub.i
[0068] Thus, when the internal combustion engine is under low load,
due to the presence of .DELTA.P.sub.i, the torque of the internal
combustion engine may be improved. When the load of the internal
combustion engine is increasing, as described above, the rising
range of .DELTA.P.sub.i is small, so the influence on the
backpressure P is limited.
[0069] If the exhaust passage is also installed with other
apparatus therein which increases the exhaust backpressure, such as
a muffler, and is located downstream of the apparatus provided by
the present invention, then, the exhaust gas discharged by the
internal combustion engine firstly passes through the apparatus
provided by the present invention, and then through other apparatus
or device for exhaust gas treatment, and after that, passes through
the pipe and is discharged into the atmosphere. The exhaust
backpressure P is approximately equal to the sum of external
atmospheric pressure P.sub.0 and pressure drop .DELTA.P.sub.i of
the apparatus per se of the present invention and other apparatus
or device for exhaust gas treatment, i.e.:
P=P.sub.0+.DELTA.P+.DELTA.P.sub.i
[0070] Although, in comparison with the case in which the apparatus
of the present invention is not used, the newly introduced
apparatus of the present invention produces a pressure drop
.DELTA.P.sub.i, but as the high-temperature exhaust gas when the
internal combustion engine is under intermediate and high load is
rapidly cooled when passing through the apparatus of the present
invention, so that the flow rate is largely decreased. As the
pressure drop is proportional to the square of the flow rate, so
the pressure drop .DELTA.P when the cooled exhaust gas flow passes
through the above described other apparatus or device for exhaust
gas treatment is largely decreased in comparison with that when the
high-temperature exhaust gas passes through, thereby improving the
efficiency of the internal combustion engine. Moreover, in this
case, as described above, when the internal combustion engine is
under low load, the effect of improving the torque of the internal
combustion engine exists, similarly.
[0071] According to the above description, if there is other
apparatus for exhaust gas treatment installed in the exhaust
passage, the exhaust backpressure will be adversely affected.
However, in some cases, for environmental or other objects, it is
necessary to install an apparatus for exhaust gas treatment, such
as a muffler, in the exhaust passage. Therefore, if multiple
functions can be integrated by the apparatus provided by the
present invention, for instance, the apparatus is made to
simultaneously have the muffling function, thereby the exhaust
backpressure can be further optimized.
[0072] When other apparatus or device for exhaust gas treatment can
be omitted if their functions are integrated with the apparatus of
the present invention, this case is similar to the case in which
the apparatus of the present invention is separately installed.
Then, the exhaust backpressure of the internal combustion engine is
approximately equal to the sum of external atmospheric pressure
P.sub.0 and the pressure drop .DELTA.P.sub.i of the apparatus per
se of the present invention, i.e.:
P=P.sub.0+.DELTA.P.sub.i
[0073] This means that the pressure drop .DELTA.P brought by other
apparatus or device for exhaust gas treatment can be eliminated,
and the exhaust backpressure is greatly decreased relative to the
original situation, thereby improving the efficiency of the
internal combustion engine. Similarly, due to the existence of
.DELTA.P.sub.i, the torque when the internal combustion engine is
under low load is increased. Thus it can be seen that a more
preferred scheme is that the apparatus of the present invention can
integrate the functions of other apparatus or device for exhaust
gas treatment, and then to replace these apparatus or devices for
exhaust gas treatment. This replacement is precious for spatial
resource, for instance, very important for a floating platform like
vessel, etc., equipped with a muffler and a waste heat boiler.
[0074] It should be noted that, from the above description, it can
be seen that the principle of the cooling apparatus integrating the
waste heat recycling of the waste heat boiler lies in the recycling
of the heat absorbed after the heat exchange between the cooling
fluid and the high-temperature exhaust gas. The principle of
integrating the muffling function of the muffler lies in that the
effects of the exhaust gas, passing through the apparatus of the
present invention, being divided by cross-section expansion and gas
flow alteration, the two of which are theoretically and
realistically not contradictory. Therefore, the cooling apparatus
of the present invention may simultaneously integrate the functions
of waste heat recycling and muffling.
[0075] In order to prevent noise pollution, at present, the exhaust
passage of the internal combustion engine is generally mounted with
the muffler, which is also a main member causing the rise of the
exhaust backpressure of the internal combustion engine. The
applicant has found that, if the exhaust gas entering the housing
can be rapidly cooled, the function of enhancing the muffling
effect can be realized.
[0076] Based on the muffling principle, there are different types
of mufflers like resistive muffler, reactive muffler and impedance
composite muffler. A resistive muffler mainly uses porous
sound-absorbing materials to reduce noises. When sound waves enter
the resistive muffler, part of the sound energy is turned into heat
by friction in the pores of the porous material to be dissipated,
making the sound wave passing through the muffler be weakened. A
resistive muffler has good effect on intermediate and high
frequency, and poor effect on low frequency. A reactive muffler is
combined from chambers and ducts with abrupt interfaces, making use
of abrupt expansion or contraction of the cross-section of the pipe
to reflect back the sound waves of certain frequencies transmitting
along the pipe at the position of sudden change to the direction of
the sound source, so as to achieve the purpose of muffling. The
reactive muffler is suitable for eliminating noise of
low-to-intermediate frequency, and is poor for high-frequency
noise. Combining the resistive structure and reactive structure in
a certain manner, an impedance composite muffler is formed, which
has muffling characteristics of both.
[0077] In order to achieve good muffling effect, the following
schemes have been found which facilitate enhancing the muffling
effect: 1) multiple changes in the direction of air flow, 2) the
air flow repeatedly passing through cross-sections first
contracting and then expanding, 3) dividing the air flow into a
plurality of small tributaries and flow along a plurality of
unsmooth planes, 4) cooling the air flow.
[0078] For an internal combustion engine, on one hand, a muffler is
essential, based on the requirements of environmental protection,
and on the other hand, the muffling effect is constrained by the
result of the rise of the backpressure. Therefore, the existing
muffling technology for an internal combustion engine is often not
good to meet these expectations. For a resistive muffler, a
plurality of pores are needed to be provided in the muffler to
change and divide the air flow. The more, longer, more irregular
the pores, the better the resistive muffling effect, but the
exhaust backpressure caused by the muffler is also greater and the
loss of power that the internal combustion engine can withstand is
limited. For reactive muffling, the greater the expansion
magnification of the cross-section of the exhaust passage, that is,
the greater the volume of the muffler, the more favorable for
muffling. However, for most occasions, especially for ships etc.
which have limited accommodating spaces, the way of cross-section
expansion is difficult to apply. As to `cooling` of the air flow,
the existing muffling technology is even more difficult to achieve,
particularly in the muffler in a dense space of a ship, where not
only the cooling cannot be achieved, but to prevent a
high-temperature of several hundred .degree. C. burning the
surrounding facilities and personnel, insulation materials have to
be used for a tight wrapping up for `preserving heat`.
[0079] The method or apparatus provided by the present invention
can make use of the principle of reactive muffling to effect
muffling. Therefore, in the method or apparatus provided by the
present invention, abrupt expansion of cross-section is formed from
the exhaust gas inlet to the interior of the housing. Here, the
method or apparatus provided by the present invention at least
makes use of the principle of reactive muffling. A reactive muffler
is combined from chambers and ducts with abrupt interfaces, making
use of abrupt expansion or contraction of cross-section of the pipe
to reflect back the sound waves of certain frequencies transmitting
along the pipe at the position of sudden change to the direction of
the sound source, so as to achieve the purpose of muffling. In the
method and apparatus provided by the present invention, abrupt
expansion of cross-section is formed from the exhaust gas inlet to
the interior of the housing. The abrupt expansion of cross-section
here refers to reducing noise of the exhaust gas by making use of
the reactive muffling principle.
[0080] If the casing is made into a regular shape, e.g. a
cylindrical or other regular shape, tested by the applicant, when
the cross-sectional area of the exhaust gas inlet is 0.05 to 0.5
times the housing of the cross-sectional area, the muffling effect
is very significant. Accordingly, in a preferred embodiment, the
exhaust gas inlet cross-sectional area is 0.05 to 0.5 times the
cross-sectional area of the housing. The Applicant has also proved
that when the housing volume is 3 to 30 times the displacement of
the internal combustion engine, the muffling effect of apparatus is
more remarkable, therefore, in a more preferred embodiment, the
volume of the housing 3 is .about.30 times the displacement of the
internal combustion engine.
[0081] The muffling method provided by the present invention may
further take advantage of the principle of resistive muffling to
enhance the muffling effect. The exhaust gas can be divided into
small tributaries. According to the principle of muffling, the
exhaust gas is divided into a small tributary to enhance the
muffling effect.
[0082] If the housing is filled with padding capable of forming
gaps thereinbetween, the muffling effect may be further enhanced.
The presence of padding makes the apparatus a resistive muffler.
When the exhaust gas enters into the padding, part of the sound is
turned into heat by friction in the pores of the porous material to
be dissipated, so that the sound waves through the muffler are
weakened. The Applicant has also found that a large area of contact
of the liquid with the exhaust gas flow, per se, can absorb the
energy of sound waves to facilitate muffling.
[0083] Thus, the present invention belongs to the impedance
composite muffling, which has muffling characteristics of both
resistance and reactance. Further, the present invention cools the
high-temperature exhaust gas of hundreds of degrees Celsius down to
tens of degrees Celsius, flowing through the muffler, producing the
expansion cooling effect while enhancing the effect of the
resistance and reactance. A resistive muffler of the present
invention mainly makes use of a large number of pores formed in
materials such as the padding, since the exhaust gas is cooled, the
volume is contracted, and the flow rate is decreased, the
resistance generated when flowing through a large number of pores
is decreased by a greater range. Therefore, it is possible to use
more padding to make up more, longer and more irregular pores,
which makes the following of the present invention all higher than
existing muffler technology by several orders: frequency of changes
in the direction of airflow, the number of the times of repetition
of airflow passing through cross-sections first contracting and
then expanding, the number of the small tributaries divided from
the gas stream, and the area of an unsmooth passage formed. On the
other hand, the reactive muffling of the present invention is
achieved from abrupt expansion of the cross-sections formed from
the exhaust gas inlet to the interior of the housing. Due to the
technical solution of the present invention significantly reduces
the exhaust gas volume, which is equivalent to increasing the
expansion magnification of the cross-section of the exhaust
passage, further enhancing the reactive muffling effect. From
another perspective, in the occasions where a great expansion ratio
is required and the prior art is difficult to achieve by space
limitations, the method or apparatus provided by the present
invention can achieve that very well.
[0084] The method of muffling exhaust gas of an internal combustion
engine, provided by the present invention, at the same time, has
the above-mentioned effect of optimizing the exhaust backpressure
of an internal combustion engine. Thus, by using the method
provided by the present invention, the effect of optimizing the
exhaust backpressure of an internal combustion engine can be
achieved as well as muffling effect is achieved by using the same
apparatus. In this way, the apparatus of the present invention is
mounted to the exhaust passage of an internal combustion engine, so
there is no need to install an additional muffler on the ship. Due
to the relevant provisions of the existing regulations on the
muffling and energy saving, in the existing structure of the ship,
the exhaust passage of an internal combustion engine is installed
with a waste heat boiler and a muffler. Moreover, in the position
of the exhaust path of the internal combustion engine, there is no
extra space for installing the apparatus for optimizing the exhaust
backpressure of internal combustion engine. By use of the method
provided by the present invention, this problem can be well solved,
that is, to install the apparatus provided by the present invention
in the position of the existing muffler and replace the existing
muffler.
[0085] Further, since cooling the exhaust gas itself can achieve
the effect of muffling, the present invention also provides a
muffling method for exhaust gas of an internal combustion engine,
including: making the exhaust gas discharged from the internal
combustion engine enter into the interior of the housing through an
exhaust gas inlet of the housing, and in addition, said method
further including: making the exhaust gas entering into the
interior of the housing to come into direct contact with the
cooling liquid.
[0086] The present invention also provides a apparatus for muffling
the exhaust gas of an internal combustion engine, including: a
housing, the housing is provided with an exhaust gas inlet allowing
the exhaust gas to enter into the interior of the housing, an
exhaust gas outlet allowing the exhaust gas to be discharge out of
the housing, a cooling water inlet allowing the cooling liquid to
enter into the interior of the housing, a cooling water outlet
allowing the cooling liquid to be discharged out of the housing;
said cooling water inlet, cooling water outlet, exhaust gas inlet
and exhaust outlet are configured so that the cooling liquid and
the exhaust gas may come into contact with each other within the
housing.
[0087] The present invention also provides a system for muffling
exhaust gas of an internal combustion engine, said system
comprising an exhaust passage of the internal combustion engine,
said system further comprising an apparatus for muffling exhaust
gas of an internal combustion engine provided by the present
invention, the apparatus is installed in the exhaust passage of the
internal combustion engine.
[0088] By using the method, apparatus and system for muffling
exhaust gas of an internal combustion engine provided by the
present invention, the existing muffler can be replaced, without
the need to install other muffler. For an apparatus which can
conveniently utilize cooling water, such as vessel sailing on
natural water, can be muffled by the method, apparatus or system,
provided by the present invention, for muffling exhaust gas of an
internal combustion engine. For an apparatus using an internal
combustion engine as a power on the land, such as cars, can also
use the cooling water of an internal combustion engine as the
cooling liquid, so as to proceed muffling of the exhaust gas of an
internal combustion engine, by the method, apparatus and system
provided by the present invention.
[0089] The method, apparatus and system for muffling exhaust gas of
an internal combustion engine can also be functionally combined
with existing muffler. For example, an abrupt expansion of
cross-section is formed from the exhaust gas inlet to the interior
of the housing, thus, rapid cooling of the high-temperature exhaust
gas will further enhance the resistance muffling effect.
[0090] In the method, apparatus and system for muffling exhaust gas
of an internal combustion engine, provided by present invention,
the way of cooling water, contact between cooling water and
high-temperature exhaust gas as well as the configuration of inlet
and outlet can be the same as or similar to the method, apparatus
and system for optimizing exhaust backpressure of an internal
combustion engine as described above.
[0091] Data shows that the diesel engine exhaust gas and cooling
medium take away heat about 50% of the total fuel heat, most of
which is discharged in the form of high-temperature exhaust gas
into the atmosphere. The existing shipbuilding regulations, in
addition to environmental regulations on muffling, also requires
installing waste heat boiler in the exhaust passage of an internal
combustion engine. The waste heat boiler, also known as exhaust gas
boiler, the role of which is to recycle the heat in the exhaust
gas, in order to achieve the purpose of energy saving. The
structure of the existing waste heat boiler is a duct encapsulating
cooling water, located in the exhaust passage of the internal
combustion engine. Thus a contradiction exists: If it is desired to
more fully recover waste heat, the pipe encapsulating the cooling
water and the exhaust gas of an internal combustion engine is
required to fully contact, which would require the pipe
encapsulating the cooling water are more densely distributed in the
exhaust pipe of the internal combustion engine, which is bound to
increase exhaust resistance and the exhaust backpressure, and
thereby adversely affect the effectiveness of the internal
combustion engine. It is also because of this, the waste heat
boiler in the existing vessels does not have high heat recovery
efficiency.
[0092] In various embodiments of the method and apparatus provided
by the present invention, if the cooling liquid (cooling water) is
in direct contact with the exhaust gas for cooling exhaust gas, the
cooling water (i.e., hot water) having absorbed heat of the
high-temperature exhaust gas can be discharged and utilize the heat
therein. Thus, the method and apparatus provided by the present
invention can also perform a waste heat recovery function.
Accordingly, the method provided by the present invention further
comprises: conveying the cooling liquid which has absorbed heat of
the high-temperature exhaust gas to the heat utilization apparatus
or heat exchanger. The system provided by the present invention
further comprises a heat utilization apparatus or heat exchanger,
and a duct for conveying fluid to the heat utilization apparatus or
heat exchanger.
[0093] Some transportation of goods such as heavy oil, asphalt etc.
needs heat source to preserve heat; hot water can be utilized
directly; the apparatus using hot water to preserve heat is a heat
utilization apparatus. Some transportation of other goods, such as
refrigerated transport vessels also need a heat source (specific
scheme belonging to the scope of conventional design) is used for
cooling, the recovered waste heat by the scheme of the present
invention can meet all or part of heat requirements thereof.
[0094] Since the method and apparatus of the present invention make
use of a cooling liquid such as cooling water to absorb the large
amount of heat that brought by the high-temperature exhaust gas
that is originally to be discharged into the atmosphere at the same
time of improving the efficiency of the internal combustion engine.
The cooling water which has absorbed heat from the exhaust gas
becomes the intermediate hot, and can be directly used again, and
can also be reused after been transferred into clean hot water by
way of a liquid-liquid heat exchange with high heat exchange
efficiency. For example, a ton class ship has exhaust emissions of
about 1220 kg/h, the temperature of the exhaust gas discharged to
the atmosphere exceeds 300.degree. C. under MCR conditions (80% of
the rated power), the heat of which is all abandoned. The
temperature of the exhaust gas discharged to the atmosphere through
the apparatus of the present invention is stabilized at about
50.degree. C. or 30.degree. C. when the ship is under MCR working
conditions, allowing the heat of millions of calories per hour that
is formerly abandoned to be recycled. Accordingly, the waste heat
boiler on the exhaust pipe of the original internal combustion
engine may be completely substituted by the present apparatus.
Meanwhile, the recycled waste heat is used to produce hot water
and/or steam as required.
[0095] For this purpose, the cooling water pump of the apparatus of
the present invention is also designed to adjust the size of the
flow, by changing the amount of cooling water to achieve
temperature adjusting of the hot water produced, so as to better
adapt to the need for utilization of waste heat, to further improve
the efficiency of waste heat utilization.
BRIEF DESCRIPTION OF THE DRAWINGS
[0096] FIG. 1 is a schematic diagram of the apparatus for
optimizing exhaust backpressure of an internal combustion engine,
according to a first embodiment of the present invention;
[0097] FIG. 2 is a schematic diagram of the system for optimizing
exhaust backpressure of an internal combustion engine, according to
a first embodiment of the present invention;
[0098] FIG. 3 is a schematic diagram of the correlation between
exhaust backpressure and engine load rate, according to a first
embodiment of the present invention;
[0099] FIG. 4 is a schematic diagram of the correlation between
exhaust temperature and engine load rate, according to a first
embodiment of the present invention;
[0100] FIG. 5 is a schematic diagram of the apparatus for
optimizing exhaust backpressure of an internal combustion engine,
according to a second embodiment of the present invention;
[0101] FIG. 6 is a schematic diagram of the system for optimizing
exhaust backpressure of an internal combustion engine, according to
a third embodiment of the present invention;
[0102] FIG. 7 is a schematic diagram of the system for optimizing
exhaust backpressure of an internal combustion engine, according to
a forth embodiment of the present invention;
[0103] FIG. 8 is a schematic diagram of the apparatus for
optimizing exhaust backpressure of an internal combustion engine,
according to a fifth embodiment of the present invention;
[0104] FIG. 9 is a schematic diagram of the apparatus for
optimizing exhaust backpressure of an internal combustion engine,
according to a sixth embodiment of the present invention; and
[0105] FIG. 10 is a schematic diagram of the apparatus for
optimizing exhaust backpressure of an internal combustion engine,
according to a seventh embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0106] FIG. 1 to FIG. 4 show the apparatus and system for
optimizing exhaust backpressure of an internal combustion engine
according to the first embodiment of the present application.
[0107] As shown in FIG. 1, in this embodiment, the apparatus for
optimizing exhaust of an internal combustion engine comprises
housing 6 provided with a cooling water inlet 10 and a cooling
water outlet 11. Wherein, cooling water inlet 10 is located on the
upper portion of the side surface of the housing, and cooling water
outlet 11 is located on the lower portion of the side surface of
the housing. Under the effect of gravity, cooling water entering
the housing from cooling water inlet 10 pass through from top to
bottom, and is discharged through cooling water outlet 11.
[0108] The housing 6 is also provided with an exhaust gas intake
pipe 8 and an exhaust gas outlet 9. Wherein, the exhaust gas intake
pipe 8 extends into the interior of the housing, the pipe orifice
extending into the interior of the housing being an exhaust gas
inlet 7. The exhaust gas inlet 7 is located at the bottom of the
housing, and the exhaust gas outlet 9 is located at the top of the
housing. The exhaust gas entering housing 6 from exhaust gas inlet
7 passes through in the interior of the housing from bottom to top
and is discharged through exhaust gas outlet 9.
[0109] Wherein, the cooling water outlet 11 is located below the
exhaust gas inlet 7 in the direction of gravity, so that the
cooling water flowing to or falling onto the bottom of the housing
does not enter exhaust gas intake pipe 8 through exhaust gas inlet
7 under the effect of gravity.
[0110] Padding which forms gaps thereinbetween is filled within the
housing 6, form padding layer 12. A water distributor 14 is
provided above padding layer 12.
[0111] Further, in order to prevent the cooling water from entering
exhaust gas intake pipe 8 from exhaust gas inlet 7, a water baffle
13 is also provided between exhaust gas inlet 7 and padding layer
12. Water baffle 13 is located right above exhaust gas inlet 7,
completely blocking the liquid from top to bottom in the vertical
direction to not allow the liquid into exhaust gas inlet 7. The
edge part of the upper surface of water baffle 13 is lower than the
central part, so that the rinsing water flowing to or falling onto
water baffle 13 further flows to or falls onto the bottom of the
housing, which further prevents the rinsing water from entering
exhaust gas inlet 7.
[0112] Hereby exhaust gas intake pipe 8 and exhaust gas inlet 7 are
configured to make exhaust gas smoothly reaches inlet 7, and
avoiding water baffle 13, and then enters into the housing, in
order that the high-temperature and high velocity exhaust gas
discharged from an internal combustion engine does not turn
direction suddenly before reaching exhaust gas inlet 7 due to the
obstruction of water baffle 13, causing a large exhaust
resistance.
[0113] As shown in FIGS. 1 and 2, in use, apparatus 5 for
optimizing exhaust backpressure is mounted in the exhaust passage
of an internal combustion engine of a ship, the apparatus together
with the exhaust passage of an internal combustion engine
constituting a system for optimizing exhaust backpressure of an
internal combustion engine. The internal combustion engine of the
ship is equipped with a turbocharger 2 thereon. In the existing
structure of a ship, an exhaust passage of an internal combustion
engine is installed with a waste heat boiler and a muffler
according to the relevant provisions of the existing regulations on
muffling and energy efficiency; moreover, there is no surplus space
for further installation of device with large dimensions in the
place where the exhaust passage of the exhaust gas from an internal
combustion engine. In the present embodiment, apparatus 5 for
optimizing exhaust backpressure of an internal combustion engine is
mounted in a muffler's position in an existing ship, replacing the
original muffler and waster heat boiler. Exhaust gas intake pipe 8
communicates with exhaust pipe 3 of an internal combustion engine,
and chimney 4 communicates with exhaust gas outlet 9. Further, in
the present embodiment, the system for optimizing exhaust
backpressure of an internal combustion engine may also include
cooling water inlet pipe 16, cooling water outlet pipe 17, pump 18,
control valve 19, heat exchanger 20, and heat utilization apparatus
21, wherein cooling water inlet pipe 16, apparatus 5 for optimizing
exhaust backpressure of an internal combustion engine, cooling
water drain pipe 17 constitutes a flow path of cooling water. Heat
exchanger 20 is mounted on the cooling water drain pipe 17 for
transferring the heat of the cooling water having absorbed heat to
another fluid, and for further transferring to heat utilization
apparatus 21 for utilization.
[0114] The apparatus and system of the present embodiment is used
by the following method: when the ship is sailing in the ocean, the
internal combustion engine works to produce high-temperature
exhaust gas (approximately 500.degree. C. or so), which is
discharged through exhaust pipe of the internal combustion engine
and then enters the housing of the apparatus for optimizing exhaust
backpressure of an internal combustion engine through exhaust gas
inlet pipe; cooling water inlet pipe extracts sea water directly
from its immediate natural environment, and sea water is conveyed
into the housing of the apparatus for optimizing exhaust
backpressure of an internal combustion engine via pump. Under the
effect of exhaust pressure and natural diffusion, exhaust gas flows
by in the interior of the housing from bottom to top; under the
effect of gravity, sea water flows by in the interior of the
housing from top to bottom. High-temperature exhaust gas is divided
into small tributaries in padding layer, and comes into contact
with sea water to be quickly cooled. The cooled exhaust gas
(approximately 30.degree. C. to 80.degree. C. after passing through
padding layer) is discharged into the atmosphere through the
chimney. Sea water having absorbed heat is drained from the cooling
water outlet, and then flows through the cooling water drain pipe
to transfer heat to another fluid via heat exchanger, and then is
discharged into the ocean. Another fluid that has absorbed heat in
the heat exchanger is conveyed to heat utilization apparatus to be
utilized.
[0115] The above embodiment utilizes padding layer having large
gaps to divide high-temperature exhaust gas into a plurality of
small tributaries so as to provide certain amount of exhaust
resistance and rapidly cool the high-temperature exhaust gas in
padding layer. The cooled high-temperature exhaust gas has a sudden
extraction in its volume and the quantity and rate of flow thereof
declined, and the resistance caused thereby is decreased by a
larger extent. The exhaust backpressure of the internal combustion
engine is relatively lowered, so that not only the working
condition of ventilation of the internal combustion engine is
improved, but also pressure boost efficiency of the turbocharger is
enhanced. In the present embodiment, the exhaust backpressure
relatively decreases with the increase of the load, thus completely
eliminating the factors sensitive to exhaust backpressure. In
addition, as the present embodiment also provides a certain amount
of backpressure when the internal combustion engine is under low
load, the torque of the internal combustion engine is thus
increased.
[0116] In the present embodiment, apparatus 5 for optimizing
exhaust backpressure of an internal combustion engine also plays a
role of a muffler. The principle of muffling pertains to the
impedance composite muffling, having both muffling characteristics
of resistance and reactance. As the high-temperature exhaust gas of
hundreds of degrees Celsius is cooled down to several tens of
degrees Celsius, producing a cooling expansion effect of
simultaneously enhancing muffling effect of resistance and
reactance, thus a better muffling effect is obtained than prior
art.
[0117] A ton class vessel is installed with the system for
optimizing exhaust backpressure of an internal combustion engine
provided by the embodiment. The main pushing diesel engine
displacement thereof is P=336 liters, combusting heavy oil with
sulfur content of 2% to 3% mm. According to the spatial conditions
along the path of the exhaust passage of the internal combustion
engine, the volume of the housing of the apparatus for optimizing
exhaust backpressure of an internal combustion engine is selected
in the scope of 3-30 times of exhaust amount of the internal
combustion engine. According to size of the exhaust gas intake pipe
3, cross-sectional area of the exhaust gas intake pipe is 0.3
m.sup.2, and cross-section area of housing is selected according to
0.05-0.5 time thereof, then the volume of the housing is selected
as 5.3 m.sup.3, cross-sectional area selected as 1.8 m.sup.2. An
apparatus for optimizing exhaust backpressure of an internal
combustion engine is installed on the exhaust passage of the main
pushing diesel internal combustion engine, and the main pushing
internal combustion engine of that ship is no longer configured
with muffler and waste heat boiler.
[0118] The cooling water conveyed to the apparatus for optimizing
exhaust backpressure of an internal combustion engine is extracted
from sea water by pump, the amount of cooling water being
controlled to be 20-100 m.sup.3/h.
[0119] Tested by the applicant, after the above vessel applied with
this embodiment, the exhaust noise of the vessel is reduced by 23
db.
[0120] FIG. 3 is a schematic diagram showing the relationship
between the exhaust backpressure of the vessel and load rate of the
internal combustion engine that are tested by the applicant in the
first embodiment, wherein the data of the prior art is obtained by
testing the vessel (other configuration are the same as the
configuration of the vessel of the present embodiment) mounted with
muffler and waste heat boiler. The exhaust backpressure data is
collected from exhaust gas inlet, with unit of Pa. It can be seen
from the result in the figure that after installing the apparatus
of the present invention, the exhaust backpressure of the present
embodiment is a little larger than that of the prior apparatus
(muffler) when the internal combustion engine is under low load.
With the increase of the load of an internal combustion engine, the
exhaust backpressure of the prior art increases rapidly, while the
exhaust backpressure of the present embodiment increases with a
velocity and extent much smaller than that of the prior art.
[0121] FIG. 4 is a schematic diagram showing the relationship
between exhaust gas temperature of the vessel and the load rate of
the internal combustion engine that are practically tested by the
applicant in the first embodiment, wherein the data of the prior
art is obtained by testing the vessel (other configuration are the
same as the configuration of the vessel of the present embodiment)
mounted with muffler and waste heat boiler. The data of temperature
is collected at the discharge port of the chimney. It can be seen
from the result in the figure that in a vessel of the prior art,
the temperature of the exhaust gas discharged is increased with the
increase of the load of an internal combustion engine, maximum to
about 350.degree. C. Obviously, there is a lot of waste heat in the
exhaust gas that is not utilized yet. While after installing the
apparatus of the present embodiment, the exhaust temperature has
been stable at about 30.degree. C.
[0122] FIG. 5 shows an apparatus for optimizing exhaust
backpressure of an internal combustion engine according to the
second embodiment of the present invention.
[0123] In this embodiment, different from the apparatus for
optimizing exhaust backpressure of an internal combustion engine in
the first embodiment, exhaust gas inlet 7 of the apparatus for
optimizing exhaust backpressure of an internal combustion engine is
located on the lower portion of the side surface of housing 6; in
the direction of gravity, the position of exhaust gas inlet 7 is
higher than that of rinsing water outlet 11. In this case, the
exhaust passage of the internal combustion engine communicates with
the side surface of the housing through exhaust gas inlet 8. As the
exhaust gas enters from the side surface of the housing, there is
no need for a water baffle.
[0124] The exhaust passage of the internal combustion engine
communicates with the side surface of the housing of the apparatus
for optimizing exhaust backpressure of an internal combustion
engine. In the present embodiment, the displacement of the internal
combustion engine is P=33 liter, housing volume is 0.2 m.sup.3,
cross-sectional area is 0.3 m.sup.2, cross-sectional area of
exhaust gas intake pipe is 0.06 m.sup.2.
[0125] FIG. 6 illustrates a system for optimizing exhaust
backpressure of an internal combustion engine according to the
third embodiment of the present invention.
[0126] Different from the system for optimizing exhaust
backpressure of an internal combustion engine in the first
embodiment, in this embodiment, the cooling water in the system for
optimizing exhaust backpressure of an internal combustion engine is
taken from the cooling water of the internal combustion engine, the
cooling water which has absorbed heat can be directed drained in
the same way as the cooling water of the internal combustion
engine.
[0127] FIG. 7 illustrates a system for optimizing exhaust
backpressure of an internal combustion engine according to the
forth embodiment of the present invention.
[0128] Different from the system for optimizing exhaust
backpressure of an internal combustion engine according to the
first embodiment, in this embodiment, the system for optimizing
exhaust backpressure of an internal combustion engine, in addition
to including a pipe conveying the fluid of the housing to heat
exchanger 20, also includes a pipe conveying the fluid of heat
exchanger 20 to the housing.
[0129] In this kind of system for optimizing exhaust backpressure
of an internal combustion engine, the cooling water that has
absorbed heat from high-temperature exhaust gas is conveyed to the
housing to act as cooling water again after passing through heat
exchanger 20, so as to realize recycling utilization.
[0130] Further, the system for optimizing exhaust backpressure of
an internal combustion engine in this embodiment also includes
impurity separator 22 installed in the cooling water drain pipe for
filtering the impurities in the cooling water, discharging the
impurities from impurity discharge pipe 24, so as to prevent
particles brought by the cooling water from accumulating too much.
Impurity separator 22 has the function of adding cooling water at
the same time, supplementing through cooling water supplementing
pipe 23 the cooling water decreased due to evaporation.
[0131] FIG. 8 illustrates the apparatus for optimizing exhaust
backpressure of an internal combustion engine according to the
fifth embodiment.
[0132] In this embodiment, heat dissipating member 25 is provided
in the housing of the apparatus for optimizing exhaust backpressure
of an internal combustion engine, i.e. cooling member. Heat
dissipating member 25 is composed of heat pipe 26, heat absorbing
sheet 27 and heat dissipating sheet 28. Heat absorbing sheet 27 is
located in the interior of the housing, made of good heat
conductor, for dividing the exhaust gas into small tributaries and
absorbing the heat in the exhaust gas. Heat dissipating sheet 28 is
located outside of the housing, made of good heat conductor, for
releasing heat into the environment. Heat pipe 26 connects heat
absorbing sheet 27 and heat dissipating sheet 28, made of good heat
conductor, for transferring the heat absorbed by the heat absorbing
sheet to the heat dissipating sheet.
[0133] When the high-temperature exhaust gas discharged from the
internal combustion engine passes through the apparatus in this
embodiment, it is divided by heat absorbing sheet 27 into small
tributaries, and is cooled at the same time through heat exchanging
with heat dissipating member 25.
[0134] The apparatus for optimizing exhaust backpressure of an
internal combustion engine in this embodiment may also be directly
installed in device using internal combustion engine as the power
on the land, such as automobiles.
[0135] FIG. 9 illustrates the apparatus for optimizing exhaust
backpressure of an internal combustion engine according to the
sixth embodiment of the present invention.
[0136] Cooling pipe 29 allowing cooling water flowing therein is
provided in the housing of the apparatus for optimizing exhaust
backpressure of an internal combustion engine in this embodiment,
i.e. cooling member. Cooling pipe 29 is densely distributed in the
housing, and thus may acts to divide the exhaust gas into small
tributaries.
[0137] In use, cooling water is kept flowing in the cooling pipe,
and the exhaust gas is rapidly cooled during the process of being
divided into small tributaries. The cooling water forms vapor after
absorbing the heat from the high-temperature exhaust gas, and the
vapor formed may be conveyed to heat utilization apparatus to be
directly utilized.
[0138] The apparatus in this embodiment may be installed on the
ship, the cooling water being taken from the sea water, river water
or lake water from a natural water body. Cooling water may also use
the cooling water of the internal combustion engine. The apparatus
may also be installed in an automobile, and the cooling water may
also use the cooling water of the internal combustion engine.
[0139] FIG. 10 illustrates the apparatus for optimizing exhaust
backpressure of an internal combustion engine according to the
seventh embodiment of the present invention.
[0140] The apparatus for optimizing exhaust backpressure of an
internal combustion engine in this embodiment includes housing 6
provided with exhaust gas inlet 7 and exhaust gas outlet 9.
Different from above, no abrupt expansion of cross-sections is
formed from exhaust gas inlet 7 to the interior of the housing,
wherein the existence of exhaust gas inlet 9 reduces the
cross-section of the exhaust passage so as to provide a certain
amount of exhaust resistance.
[0141] The apparatus in this embodiment also includes sprayer 15,
for spraying cooling water to the interior of the housing, thereby
rapidly reducing the temperature of the high-temperature exhaust
gas. The cooling water which has absorbed heat is discharged from
cooling water outlet 11.
* * * * *