U.S. patent application number 10/626926 was filed with the patent office on 2004-05-06 for cooling system for turbocharged internal combustion engine.
Invention is credited to Jenni, Hans-Rudolf, Wenger, Urs, Wizgall, Eberhard.
Application Number | 20040083730 10/626926 |
Document ID | / |
Family ID | 32180103 |
Filed Date | 2004-05-06 |
United States Patent
Application |
20040083730 |
Kind Code |
A1 |
Wizgall, Eberhard ; et
al. |
May 6, 2004 |
Cooling system for turbocharged internal combustion engine
Abstract
Turbine casing for a turbocharged internal combustion engine for
marine applications with an exhaust manifold that is single-piece
formed with the turbine casing, and a cooling facility surrounding
both the turbine casing as well as the exhaust manifold. The
cooling facility is a hollow space, formed by the double wall that
can be filled with coolant, whereby the coolant preferably is
ocean/lake water. A separate cooling circuit from the cooling
facility of the combined turbine casing and exhaust manifold is
provided for the cooling of a bearing housing, which is used to
support a turbine bearing.
Inventors: |
Wizgall, Eberhard;
(Illingen, DE) ; Jenni, Hans-Rudolf; (Kaltacker,
CH) ; Wenger, Urs; (Leutwill, CH) |
Correspondence
Address: |
INTELLECTUAL PROPERTY GROUP
FREDRIKSON & BYRON, P.A.
4000 PILLSBURY CENTER
200 SOUTH SIXTH STREET
MINNEAPOLIS
MN
55402
US
|
Family ID: |
32180103 |
Appl. No.: |
10/626926 |
Filed: |
July 25, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60450073 |
Feb 25, 2003 |
|
|
|
Current U.S.
Class: |
60/614 ;
60/320 |
Current CPC
Class: |
F01D 25/26 20130101;
F05D 2220/40 20130101; F05D 2240/14 20130101; F01D 25/14 20130101;
F02B 37/02 20130101; Y02T 10/12 20130101; F02B 39/005 20130101;
F05D 2260/232 20130101; F01N 3/04 20130101; F01N 13/10 20130101;
F01N 3/046 20130101; Y02T 10/144 20130101; F02B 37/00 20130101;
Y02T 10/20 20130101 |
Class at
Publication: |
060/614 ;
060/320 |
International
Class: |
F01N 005/02; F01N
003/02 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 26, 2002 |
DE |
102 35 189.9 |
Claims
What is claimed is:
1. An engine comprising: a turbine casing; an exhaust manifold
coupled to the turbine casing wherein the turbine casing and the
exhaust manifold are formed as one piece; and a cooling structure
integrated in the turbine casing and the exhaust manifold wherein
the cooling structure allows a coolant to circulate around portions
of the turbine casing and the exhaust manifold.
2. The engine according to claim 1 wherein he cooling structure
comprises: an inner wall; an outer wall spaced from the inner wall
to define a cavity there between wherein the coolant circulates in
the cavity.
3. The engine according to claim 2 wherein the outer wall of the
cooling structure forms at least a portion of the turbine casing
and the exhaust manifold.
4. The engine according to claim 1 wherein the cooling structure
has an input for each bend of the exhaust manifold.
5. The engine according to claim 1 wherein the cooling structure
has an outlet positioned near an exhaust gas outlet of the turbine
casing.
6. The engine according to claim 5 wherein the outlet comprises a
plurality of outlets positioned around the exhaust gas outlet.
7. An engine cooling system comprising a first cooling circuit for
cooling an engine block; and a second cooling circuit for cooling a
turbine bearing housing, the second cooling circuit having an input
coupled to the first cooing circuit at a first location and an
output coupled to the first cooling circuit at a second
location.
8. The system according to claim 7 wherein the first cooling
circuit has a pump and the first location is downstream of the pump
and the second location is upstream of the pump.
9. The engine according to claim 1 wherein the turbine casing is
made of a metal selected from the group consisting of a low-alloy
steel, a gray cast iron and aluminum.
10. An engine comprising: a turbine casing; an exhaust manifold
coupled to the turbine casing wherein the turbine casing and the
exhaust manifold are formed as one piece; a cooling structure
integrated in the turbine casing and the exhaust manifold wherein
the cooling structure allows a coolant to circulate around portions
of the turbine casing and the exhaust manifold; and an engine
cooling system comprising a first cooling circuit for cooling an
engine block; and a second cooling circuit for cooling a turbine
bearing housing, the second cooling circuit having an input coupled
to the first cooing circuit at a first location and an output
coupled to the first cooling circuit at a second location.
11. The engine according to claim 10 wherein he cooling structure
comprises: an inner wall; an outer wall spaced from the inner wall
to define a cavity there between wherein the coolant circulates in
the cavity.
12. The engine according to claim 11 wherein the outer wall of the
cooling structure forms at least a portion of the turbine casing
and the exhaust manifold.
13. The engine according to claim 10 wherein the cooling structure
has an input for each bend of the exhaust manifold.
14. The engine according to claim 10 wherein the cooling structure
has an outlet positioned near an exhaust gas outlet of the turbine
casing.
15. The engine according to claim 14 wherein the outlet comprises a
plurality of outlets positioned around the exhaust gas outlet.
16. The system according to claim 10 wherein the first cooling
circuit has a pump and the first location is downstream of the pump
and the second location is upstream of the pump.
17. The engine according to claim 10 wherein the turbine casing is
made of a metal selected from the group consisting of a low-alloy
steel, a gray cast iron and aluminum.
18. A personal watercraft comprising: a hull; a deck positioned on
the hull; a propulsion device; an engine for driving the propulsion
device; the engine comprising: a turbine casing; an exhaust
manifold coupled to the turbine casing wherein the turbine casing
and the exhaust manifold are formed as one piece; and a cooling
structure integrated in the turbine casing and the exhaust manifold
wherein the cooling structure allows a coolant to circulate around
portions of the turbine casing and the exhaust manifold.
19. The personal watercraft according to claim 18 further
comprising: a first cooling circuit for cooling an engine block;
and a second cooling circuit for cooling a turbine bearing housing,
the second cooling circuit having an input coupled to the first
cooing circuit at a first location and an output coupled to the
first cooling circuit at a second location.
20. The personal watercraft according to claim 18 wherein the
turbine casing is made of a metal selected from the group
consisting of a low-alloy steel, a gray cast iron and aluminum.
Description
RELATED APPLICATIONS
[0001] This application is related to U.S. Provisional Application
No. 60/450,073, filed on Feb. 25, 2003, the entire disclosure of
which is hereby incorporated by reference.
[0002] This application is related to and claims priority to German
Patent Application No. 102 35 189.9, filed on Jul. 26, 2002, the
entire disclosure of which is hereby incorporated by reference.
FIELD OF THE INVENTION
[0003] The following invention relates to a cooling system. More
particularly, the invention relates to a cooling system for a
turbocharged internal combustion engine for marine applications,
and a turbine casing with an integral exhaust manifold.
BACKGROUND OF THE INVENTION
[0004] Turbocharged internal combustion engines for marine
applications such as watercraft, boats, or recreational sporting
equipment such as personal watercraft are known. In such internal
combustion engines, the cooling of exhaust leading components such
as the exhaust manifold, the turbine casing, and the exhaust gas
turbocharger under adaptation of the special circumstances of
operation in water, is performed differently than internal
combustion engines intended for use in offshore vehicles. In this
manner, the exhaust manifold housing of known internal combustion
engines for marine applications have a double-walled housing
chamber with a water jacket design. Ocean/lake water is led through
the hollow space formed by the double-walled housing chamber for
cooling of the exhaust manifold. The separately formed turbine
casing of known internal combustion engines for marine applications
is also cooled by means of water-cooling.
SUMMARY OF THE INVENTION
[0005] According to the present invention, a turbine casing
characterized by an exhaust manifold that is formed as a single
piece with the turbine casing, and a cooling facility encompassing
both the turbine as well as the exhaust manifold is provided. In
addition, the invention provides for a turbocharged internal
combustion engine defined by a turbine casing with the above
characteristics, as well as a method for cooling a turbocharged
internal combustion engine where sea/lake water is led through a
cooling facility surrounding both the exhaust manifold and the
turbine, in order to cool them. Furthermore, the invention provides
for cooling the turbine bearings of the turbocharger by providing a
separate cooling circuit, whereby coolant is diverted off and led
back to the engine cooling circuit.
[0006] Therefore, according to the invention, the turbine casing
and the exhaust manifold housing are formed together as a single
unit, and are surrounded by a common cooling facility. Thus, as an
advantage, the interface between the until now separately formed
components of the turbine casing and the exhaust manifold housing
is no longer required. This has the consequence that on both
housings, flanges for the transfer of exhaust gas and coolant
between the two housings no longer must be given. Furthermore, the
invention saves weight and requires one less sealing location.
Particularly, the previously required bolted connection between the
exhaust manifold housing and turbine casing, which is subject to
extreme stress due to the cyclic thermal growth, is no longer
required. Of particular advantage is the possibility to surround
both single-piece formed housings by a common cooling facility,
preferably a water jacket, which encapsulates both hot gas-leading
areas of the two component housings without interruption through a
flange.
[0007] Due to the arrangement of the invention, the cooling
facility is a cavity, formed by a double wall and filled with
coolant, whereby preferably each single bend of the exhaust
manifold is provided with a coolant inlet. This feature ensures a
symmetrical and even inflow of the coolant in the cooling facility.
The coolant outlet is provided further downstream on the turbine so
that coolant first flows around the exhaust manifold, then around
the turbine, and then exits. For marine applications of the
turbocharged internal combustion engine subject to the invention,
ocean/lake water is especially suitable as the coolant for the
cooling facility.
[0008] Due to the improved cooling effect achieved by the
invention, it is possible to form a turbine casing with less
heat-resistant materials (e. g., low-alloy steel, gray cast iron,
aluminum) compared to known turbine casings. These materials have
better casting characteristics and are more cost-efficient in
comparison to high-alloy steel.
[0009] As a particular design advantage of the invention, a
separate cooling circuit from the cooling facility of the turbine
casing is intended for cooling a bearing housing. This separate
cooling circuit preferably branches off from the already given
engine cooling circuit. Thus, according to the invention, separate
cooling of the turbine casing and the bearing housing takes place,
whereby the first is cooled with a very cold coolant; preferably
ocean/lake water with a maximum temperature of 30 to 35.degree. C.,
and the later with a warmer coolant; preferably the coolant from
the engine coolant circuit with a temperature generally exceeding
70.degree. C. This feature effects a strong cooling of the turbine
casing with "cold" ocean/lake water, and thus decreases the surface
temperature of the combined exhaust manifold housing and turbine
casing to corresponding limit values given by marine regulations.
With the use of the warmer coolant from the engine coolant circuit
for the cooling of the bearing housing the bearing friction is
reduced in comparison to cooling with a colder coolant. This
results in improved response characteristics and in an improved
overall efficiency factor of the turbocharger.
[0010] A method for cooling of a turbocharged internal combustion
engine for marine applications in accordance with the invention is
given by removal of coolant from an engine block, thermostat,
cooler and coolant pump-which form the coolant circuit of the
engine-for cooling of a turbine bearing from the turbocharger and
leading it back into this circuit after cooling the turbine bearing
housing and to provide separate cooling for the exhaust manifold
and turbine via ocean/lake water, which has been led through a
cooling facility surrounding both the exhaust manifold and the
turbine. Preferably, the coolant for cooling of the turbine bearing
housing is taken from the coolant circuit upstream of the coolant
pump and led back into the coolant circuit downstream of the
coolant pump.
[0011] The aforementioned characteristics and those described in
the following can be utilized not only in the combinations
mentioned, but also in other combinations or by themselves, within
the scope of this invention.
DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a cross-sectional view of a combined turbine
casing and exhaust manifold according to a preferred embodiment of
the present invention.
[0013] FIG. 2 is a cross-sectional view of the combined turbine
casing and exhaust manifold taken along lines II-II of FIG. 3.
[0014] FIG. 3 is a partial cross-sectional view of the combined
turbine casing and exhaust manifold in accordance with a preferred
embodiment of the invention.
[0015] FIG. 4 is a perspective view of the combined turbine casing
and exhaust manifold of FIGS. 1-3, along with additional components
for installation.
[0016] FIG. 5 is a schematic representation of the coolant flow in
a turbocharged internal combustion engine.
[0017] FIG. 6 is a schematic representation of the engine cooling
circuit of a turbocharged internal combustion engine, including the
turbine bearing housing cooling circuit.
DETAILED DESCRIPTION
[0018] FIG. 1 show a turbine casing 10 for a turbocharged internal
combustion engine for marine applications, characterized by an
exhaust manifold 12, 14 which is formed as a single piece with the
turbine casing, and a cooling facility 18, 20, 22 encompassing both
a turbine 16 as well as the exhaust manifold 12, 14. Additionally,
the cooling facility is formed by a double-walled 18, 20 cavity 22,
which can be subjected to the admission of coolant. A coolant inlet
28 may be provided for at each single bend 12 of the exhaust
manifold, as shown in FIG. 3. Also, a coolant outlet 44 may be
provided for at the turbine casing, as shown in FIG. 4. The cooling
medium being used in the cooling facility 18, 20, 22 may be sea or
lake water. Furthermore, a bearing housing 32, as shown in FIG. 4,
for support of a turbine bearing may be provided, for which a
cooling circuit separate from the cooling facility 18, 20, 22 of
the turbine casing may be used for cooling the bearing housing 32.
The invention also contemplates a turbocharged internal combustion
engine for marine applications, defined by the preceding
characteristics.
[0019] As shown in FIG. 6, the invention contemplates a method for
cooling a turbocharged internal combustion engine for marine
applications, whereby an engine block 52 is connected in a cooling
circuit 50 with a thermostat 54, a cooler 56 and a coolant pump 58,
and for cooling of a turbine bearing housing of the turbocharger
for which coolant is diverted off and led back to the cooling
circuit 50, and for which sea/lake water is led through the cooling
facility 18, 20, 22 surrounding both the exhaust manifold and the
turbine, in order to cool the exhaust manifold 12, 14 and the
turbine 16. The cooling medium may be taken from the cooling
circuit 50 after the coolant pump 58 and reentered into the coolant
circuit 50 again ahead of the coolant pump 58. Furthermore, the
sea/lake water may be symmetrically led through each single bend 12
of the exhaust manifold into the cooling facility 18, 20, 22.
[0020] FIG. 1 shows the turbine casing 10 in accordance with the
invention, on which the usually separated components-exhaust
manifold housing and turbine casing-are formed as a single piece.
The turbine casing 10 in accordance with the invention consists of
two single bends 12 (also see FIGS. 2 and 3) with exhaust gas guide
ducts 14 that lead into the turbine 16. It will be appreciated that
the present invention can be used with turbine casings that have
more than two bends.
[0021] The turbine casing 10 in accordance with the invention
consists of a double wall 18, 20 which forms the hollow space 22
between the walls 18, 20. In the sectional views of FIGS. 1 to 3,
the hollow space 22 is indicated as a duct that is interrupted by
ribs 24, whereby the ribs 24 are the connecting bridges between the
two walls 18 and 20 of the double wall.
[0022] Coolant, especially ocean/lake water, is admitted to the
hollow space 22. For this purpose, a flange 26 with a coolant inlet
opening 28 each is provided for in the area of every single bend
12. Both single bends 12 and the coolant inlet openings 28 are
preferably formed symmetrical, in order to enable a nearly uniform
flow with ocean/lake water.
[0023] The ocean/lake water used for cooling, in accordance with
the invention, thus flows into the hollow space 22 through the
coolant inlet opening 28, whereby the hollow space 22 is formed in
such a manner that the water flows evenly around the hot,
gas-leading areas. At first, the ocean/lake water flows around the
exhaust gas guide ducts 14 of the two single bends 12 and
afterwards around the turbine 16. Only locations in the interior of
the turbine casing that cannot be cooled well can, if required, be
formed as a cast-in steel insert (instead of solid aluminum).
[0024] This steel insert (not shown) can be a finish-cast part, not
requiring refinishing and thus cost effective.
[0025] In the area of the exhaust gas guide duct 14 in FIG. 1, an
opening is shown in the worm of the turbine 16, which forms a
channel 30 for a bypass-supply (also see FIG. 3).
[0026] FIG. 4 shows a perspective view of the turbine casing in
accordance with the invention in the assembly position and with
several further components. In particular, FIG. 4 shows the bearing
housing 32 and a compressor housing 38. Also shown in FIG. 4 is a
flange 40 on the turbine casing 10 for an exhaust gas pipe 46 (see
FIG. 5). Provided on the flange 40 are an exhaust gas outlet
opening 42 (turbine outlet) and outlet openings 44 of the hollow
space 22 through which the ocean/lake water can emerge in order to
cool the turbine casing 10. In the shown design example of the
invention, ocean/lake water emerges through the outlet openings 44
and is led further in a corresponding double-wall hollow space of
the exhaust gas pipe 46, thus also supporting the cooling of the
exhaust gas pipe.
[0027] For cooling of the bearing housing 32, a coolant circuit is
provided in accordance with the invention, as shown in FIG. 6. The
coolant circuit 50 includes an engine block 52 that is connected
with hoses 60 via a thermostat 54 to a cooler 56 and a coolant pump
58. 20 From the engine cooling circuit 50, coolant, according to
the invention, is diverted via an auxiliary line 62 for cooling of
the turbine bearing in the bearing housing 32, and afterwards led
back into the coolant circuit 50 again. Preferably, this
branching-off of coolant is carried out in front of the coolant
pump 58, as indicated in FIG. 6, and the return of the coolant into
the circuit takes place downstream of the coolant pump 58, ahead of
the engine block 52.
[0028] The complete coolant path of a turbocharged internal
combustion engine in accordance with the invention is represented
schematically in FIG. 5, whereby the coolant flow is indicated with
arrows. FIG. 5 shows the engine block 52 with intake manifolds 53
onto which, according to the invention, a turbine casing 10 with
two single bends 12 and the corresponding exhaust gas ducts 14 and
the turbine 16 connects. An exhaust pipe 46 connects at the exhaust
gas outlet opening 42 (see FIG. 4). Also arranged on the turbine
casing 10 are a bearing housing 32 and compressor housing 38.
Exhaust gas exits the engine block 52 into the single bends 12 as
indicated by dashed arrows A and flows through the exhaust gas
guide ducts 14 into the turbine 16, and from there into the exhaust
pipe 46 where they then emit. The flow of the ocean/lake water for
cooling of the turbine casing 10 is indicated by arrows S and takes
place as described before. Coolant K from the engine cooling
circuit as shown by arrows K is led into the bearing housing 32 via
a coolant inlet 34 (also see FIGS. 5 and 6) and led out of the
coolant circuit again via a coolant outlet 36.
* * * * *