U.S. patent application number 13/120035 was filed with the patent office on 2011-10-20 for exhaust flow insulator for an exhaust system device.
This patent application is currently assigned to BorgWarner Inc.. Invention is credited to Volker Joergl, Timm Kiener.
Application Number | 20110252775 13/120035 |
Document ID | / |
Family ID | 42074121 |
Filed Date | 2011-10-20 |
United States Patent
Application |
20110252775 |
Kind Code |
A1 |
Joergl; Volker ; et
al. |
October 20, 2011 |
EXHAUST FLOW INSULATOR FOR AN EXHAUST SYSTEM DEVICE
Abstract
An exhaust system device comprising a liquid-cooled non-ferrous
housing including a liquid cooling passage and defining a path for
exhaust gas, and an exhaust flow insulator carried in the exhaust
gas path of the housing to convey exhaust gas through the housing
to limit heat transfer from exhaust gas to the housing.
Inventors: |
Joergl; Volker;
(Breitenfurt, AT) ; Kiener; Timm; (Aspeig,
DE) |
Assignee: |
BorgWarner Inc.
Auburn Hills
MI
|
Family ID: |
42074121 |
Appl. No.: |
13/120035 |
Filed: |
September 25, 2009 |
PCT Filed: |
September 25, 2009 |
PCT NO: |
PCT/US09/58301 |
371 Date: |
July 6, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61101812 |
Oct 1, 2008 |
|
|
|
Current U.S.
Class: |
60/321 |
Current CPC
Class: |
F01N 13/102 20130101;
F02C 6/12 20130101; F05D 2220/40 20130101; F01N 2530/26 20130101;
F01N 3/046 20130101; F01N 13/146 20130101; F01D 25/145 20130101;
Y02T 10/12 20130101; F01N 2310/06 20130101; F01N 2510/02 20130101;
Y02T 10/20 20130101; F01N 13/143 20130101; F02B 39/005
20130101 |
Class at
Publication: |
60/321 |
International
Class: |
F01N 3/04 20060101
F01N003/04 |
Claims
1. An exhaust system device comprising: a liquid-cooled non-ferrous
housing including an inlet, an outlet, a path for exhaust gas
between the inlet and the outlet, and a liquid cooling passage
adjacent the exhaust gas path; and a exhaust flow insulator carried
in the exhaust gas path of the housing to convey exhaust gas
through the housing to limit heat transfer from exhaust gas to the
housing, wherein said insulator is composed of at least one of a
ferrous material or a ceramic material.
2. An exhaust system device as set forth in claim 1 wherein the
housing includes at least one of an exhaust manifold housing or a
turbocharger turbine housing, and the insulator is carried in the
exhaust gas path of the housing substantially from the inlet and
substantially to the outlet.
3. An exhaust system device as set forth in claim 1, wherein at
least a portion of the insulator is in direct contact with the
housing.
4. An exhaust system device as set forth in claim 3, wherein at
least a portion of the insulator is a ceramic coating.
5. An exhaust system device as set forth in claim 1 wherein the
insulator is comprised of multiple portions.
6. An exhaust system device as set forth in claim 5 wherein the
multiple portions include flanges coupled to one another along a
seam.
7. An exhaust system device as set forth in claim 1 wherein the
housing is cast from aluminum and the insulator is manufactured
from steel.
8. An exhaust system device as set forth in claim 1 wherein the
housing is cast around the insulator.
9. An exhaust system device as set forth in claim 1 wherein the
housing is comprised of multiple portions coupled together.
10. An exhaust system device as set forth in claim 9 wherein the
housing is of a clamshell configuration having one housing portion
coupled to another housing portion.
11. An exhaust system device as set forth in claim 1, further
comprising an insulating void between the insulator and the
housing.
12. An exhaust system device as set forth in claim 11 wherein the
insulator includes apertures to communicate exhaust gas from the
interior of the insulator to the insulating void between the
insulator and the housing.
13. An exhaust system device as set forth in claim 11 wherein the
insulating void is vacuum vented by a vacuum vent passage in the
housing in fluid communication at one end with the insulating void
and communicable at another end with a vacuum vent passage in an
engine.
14. An exhaust system device as set forth in claim 11, further
comprising an insulation material disposed in the insulating void
between the insulator and the housing.
15. An exhaust system device as set forth in claim 1, wherein the
insulation material is at least one of cast in place, poured into
the insulating void, assembled between portions of the housing, or
blown into the insulating void, and includes at least one of fiber
insulation, aluminum insulation, ceramic ball insulation, or
aerogel insulation.
Description
[0001] This application claims the benefit of U.S. Provisional
Application No. 61/101,812 filed Oct. 1, 2008.
TECHNICAL FIELD
[0002] The field to which the disclosure generally relates includes
internal combustion engines and, more particularly, engine exhaust
system devices.
BACKGROUND
[0003] Combustion engines use breathing systems including induction
systems to carry induction gases to engine combustion chambers, and
exhaust systems to convey exhaust gases away from the combustion
chambers. An exhaust system may include various devices, which may
include an exhaust manifold that may collect exhaust gases from a
plurality of different combustion chambers, and a turbocharger that
includes a turbine housing in downstream fluid communication with
the exhaust manifold. Other exhaust system devices may include, for
example, exhaust pipes or conduit between turbine housings and one
or more valves regulating exhaust flow between turbine
housings.
SUMMARY OF EXEMPLARY EMBODIMENTS
[0004] One exemplary embodiment includes an exhaust system device
including a liquid-cooled non-ferrous housing including an inlet,
an outlet, a path for exhaust gas between the inlet and the outlet,
and a liquid cooling passage adjacent the exhaust gas path. An
exhaust flow insulator is carried in the exhaust gas path of the
housing substantially from the inlet and substantially to the
outlet and for conveying exhaust gas through the housing to limit
heat transfer from exhaust gas to the housing. The insulator is
composed of at least one of a ferrous material or a ceramic
material.
[0005] Other exemplary embodiments will become apparent from the
detailed description provided hereinafter. It should be understood
that the detailed description and specific examples, while
disclosing exemplary embodiments of the invention, are intended for
purposes of illustration only and are not intended to limit the
scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] Exemplary embodiments will become more fully understood from
the detailed description and the accompanying drawings,
wherein:
[0007] FIG. 1 is a perspective view of an exemplary embodiment of a
portion of an engine having an exhaust system including an exhaust
manifold and a turbocharger turbine housing;
[0008] FIG. 2 is a fragmented schematic view of the exhaust
manifold and engine of FIG. 1;
[0009] FIG. 2A is a sectional end view of the exhaust manifold of
FIG. 2;
[0010] FIG. 3 is a fragmented schematic view of a second exemplary
embodiment of an exhaust manifold and engine;
[0011] FIG. 4 is a fragmented end view of the exhaust manifold and
engine of FIG. 3;
[0012] FIG. 5 is a fragmented schematic view of a third exemplary
embodiment of an exhaust manifold and engine;
[0013] FIG. 6 is a fragmented schematic view of a fourth exemplary
embodiment of an exhaust manifold and engine;
[0014] FIG. 7 is a fragmented schematic view of a fifth exemplary
embodiment of an exhaust manifold and engine;
[0015] FIG. 8 is a fragmented schematic view of a sixth exemplary
embodiment of an exhaust manifold and engine;
[0016] FIG. 9 is a fragmented schematic view of a seventh exemplary
embodiment of an exhaust manifold and engine;
[0017] FIG. 10 is a fragmented schematic view of an eighth
exemplary embodiment of an exhaust manifold and engine;
[0018] FIG. 11 is a fragmented schematic view of a ninth exemplary
embodiment of an exhaust manifold and engine;
[0019] FIG. 12 is a fragmentary sectional view of the turbocharger
turbine housing of FIG. 1;
[0020] FIG. 13 is a fragmented schematic view of a second exemplary
embodiment of a turbine housing;
[0021] FIG. 14 is a fragmented schematic view of a third exemplary
embodiment of a turbine housing;
[0022] FIG. 15 is a fragmented schematic view of a fourth exemplary
embodiment of a turbine housing;
[0023] FIG. 16 is a fragmented schematic view of a fifth exemplary
embodiment of a turbine housing;
[0024] FIG. 17 is a fragmented schematic view of a sixth exemplary
embodiment of a turbine housing;
[0025] FIG. 18 is a fragmented schematic view of a seventh
exemplary embodiment of a turbine housing;
[0026] FIG. 19 is a fragmented schematic view of an eighth
exemplary embodiment of a turbine housing; and
[0027] FIG. 20 is a fragmented schematic view of a ninth exemplary
embodiment of a turbine housing.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0028] The following description of the exemplary embodiment(s) is
merely exemplary in nature and is in no way intended to limit the
invention, its application, or uses.
[0029] FIG. 1 illustrates a portion of an exemplary engine exhaust
system 30, which may include an exhaust manifold 32 and a
turbocharger turbine 34. The exhaust system 30 may be coupled in
any suitable manner to an engine E. For example, the exhaust
manifold 32 may be fastened to a cylinder head or block B of the
engine so as to receive exhaust gas from combustion chambers (not
shown) of the engine E and convey the exhaust gas further
downstream of the engine E. Similarly, the turbine 34 may be
coupled in any suitable manner to the manifold 32 so as to receive
exhaust gas therefrom and convey the exhaust gas further downstream
to other exhaust system devices. For example, the turbine 34 may be
integrated with the manifold 32 or may be a separate device that is
fastened or otherwise connected to the manifold 32.
[0030] Other engine exhaust system architectures may be used. For
example, the exhaust manifold 32 may be integrated with a cylinder
head (not separately shown) of the engine E. In another example,
the turbine 34 may be integrated with the engine cylinder head or
integrated head/manifold, or may be a separate device that is
fastened or otherwise connected to the cylinder head or integrated
head/manifold.
[0031] Several exemplary embodiments of an exhaust manifold and a
turbine housing are described below and are similar in many
respects to one another. Accordingly, like numerals between the
embodiments generally designate like or corresponding elements
throughout the several views of the drawing figures. Additionally,
the descriptions of the embodiments are incorporated by reference
into one another and the common subject matter may generally not be
repeated. Moreover, the embodiments may include any suitable
gaskets, seals, fasteners, or any other components known to those
of ordinary skill in the art and not shown here.
[0032] The exhaust manifold 32 includes a housing 36 having a
collector 38 and one or more individual pipes 40 in fluid
communication between the collector 38 and the block B. The pipes
40 may be separated as shown, or may be integrated at their block
ends with one or more common flanges (not shown). The exhaust
manifold 32 may be of any suitable shape, and size, and may include
any suitable quantity of pipes 40, depending on the particular
application involved. Also, the manifold housing 36 may be composed
of any suitable material, for example, a non-ferrous material. The
manifold housing 36 may be cast from molten material, for example,
by die casting, investment casting, lost foam casting, or sand
casting, or by any other suitable process. In a specific example,
the manifold housing 36 is composed of die cast aluminum,
magnesium, or the like. The housing 36 may be at least partially
machined or milled. An exemplary material may include those used to
produce compressor housings, for example, 356.0 aluminum alloy.
[0033] Referring now to FIG. 2, the exhaust manifold housing 36 may
define one or more paths for exhaust gas. For example, the
collector 38 may define a common passage 42, and the pipes 40 may
define individual pipe passages 44. Upstream ends of the pipes 40
represent one or more inlets of the housing 36, and a downstream
end (shown fragmented) of the collector 38 represents an outlet of
the housing 36.
[0034] The exhaust manifold 32 may also include and one or more
insulators 46 carried in the exhaust passages of the housing 36 to
convey exhaust gas therethrough and limit heat transfer from the
exhaust gas to the housing 36. The insulator 46 may define one or
more insulating voids 48 between the insulator 46 and the housing
36 to further limit heat transfer from the exhaust gas to the
housing 36 and minimize or eliminate direct contact of exhaust gas
with the housing 36. The insulator 46 may include a collector
portion 50 and individual pipes 52 extending from the collector
portion 50. The pipes 52 may terminate in extensions 54 that may
extend beyond or outside of flanges 41 of the housing 36 and into
ports P of the engine E. As shown, the insulator 46 may extend from
the inlet(s) of the housing 36 to the outlet of the housing 36. Of
course, the insulator 46 may or may not extend 100% of the way from
the inlet(s) to the outlet of the housing 36 but may extend
substantially the entire way, for example, from about 90-100%, or
at least 50%.
[0035] The housing 36 may also include one or more liquid cooling
passages 45 that may be supplied with coolant from the engine E,
for example, via a coolant passage W. The coolant passage W may be
in communication with a water jacket in the engine manifold or
block, or with a hose or any other suitable conduit and/or source
of coolant.
[0036] As shown in FIGS. 2, 3, and 5 radial space may be provided
between the insulator extensions 54 and the housing pipes 40 to
define parallel exhaust paths--a relatively hotter path through the
insulator 46 and a relatively cooler path between the insulator 46
and the housing 36.
[0037] Referring to FIG. 2A, the insulator 46 may be constructed in
any suitable manner, for example, stamped from two or more
individual components 46a, 46b, which may be attached at a seam 56.
The seam 56 may include opposed flanges 56a, 56b, which may be
welded, crimped, fastened, and/or the like. The insulator 46 may be
composed of any suitable material that is suitable for use in
conveying exhaust gases, for example, a ferrous material. In a more
specific example, a high nickel content temperature-resistant
stainless steel may be used, for example a 1.43.xx or 1.48.xx steel
that may be less than 2 mm in wall thickness for good deep drawing
characteristics and low weight. The insulator 46 may be composed of
a relatively low tensile strength material such that the insulator
46 need only support its own weight, and does not have to seal so
that the insulator 46 need not be manufactured with close
tolerances.
[0038] In the exemplary embodiment of FIGS. 2 and 2A, the housing
36 is cast around the insulator 46 in any suitable manner. For
example, the insulator 46 may be positioned in a die cavity (not
shown), and then molten material of the housing 36 may be
introduced into the mold cavity around the insulator 46 and cooled,
to at least partially envelop the insulator 46 in the cast housing
36.
[0039] In contrast, in the exemplary embodiment of FIGS. 3 and 4, a
housing 136 may include a plurality of portions coupled together.
For example, the housing 136 may be of a clamshell configuration
wherein one housing portion 136a is coupled to another housing
portion 136b, for example, by fastening opposed flanges 137a, 137b
to one another. In this embodiment, the insulator 46 may be placed
in a first one of the housing portions 136a and then another of the
housing portions 136b may be assembled over the insulator 46 and
coupled to the first housing portion 136a in any suitable manner so
as to capture the insulator 46 in the housing 136.
[0040] In the exemplary embodiment of FIG. 5, an exhaust manifold
232 may include an exhaust flow insulator 246 having one or more
apertures 258 to communicate some exhaust gas from the interior of
the insulator 246 to an insulating void 248 between the insulator
246 and the housing 236. The apertures 258 allow for heat expansion
and gas exchange between the two aforementioned spaces. As shown,
the apertures 258 may be provided in a collector portion 250 of the
insulator 246. But the apertures 258 also or instead may be
provided in pipes 252 of the insulator 246.
[0041] In the exemplary embodiment of FIG. 6, an exhaust manifold
332 includes a vacuum vented housing 336. The housing 336 may
include flanges 341 that are coupled in close contact with outer
peripheral surfaces of the insulator pipes 52. The close contact
may provide a seal so as to prevent passage of exhaust gas between
the pipes 52 and the flanges 341. One or more of the flanges 341
may be provided with a vacuum vent passage 343 in fluid
communication at one end with an insulating void 348 of the
manifold 332 and at another end with a vacuum vent passage V in the
engine E. The engine vacuum vent passage V may be in fluid
communication with any suitable source of engine vacuum, for
example, an engine crankcase chamber (not shown) via a check valve
C shown schematically. Accordingly, hot air or exhaust gas may be
evacuated from or drawn through the insulating void 348 so as to
cool the housing 336.
[0042] In the various exemplary embodiments of FIGS. 7 through 10,
various examples of insulation materials are disposed in insulating
voids between insulators and exhaust manifold housings.
[0043] In a first example, in the exemplary embodiment of FIG. 7,
an exhaust manifold 432 includes a fiber insulation material 460
disposed in the insulating void 48 between the housing 36 and the
insulator 46. The fiber insulation material 460 may be disposed in
close, inclusive contact between the housing pipes 40 and the
insulator pipes 52. The fiber insulation material 460 may be cast
in place, assembled between housing portions, blown into the
insulating void 48 in any suitable manner, or introduced to the
void 48 in any other suitable manner. Any suitable insulation
material may be used, for example, materials similar to that used
in holding substrates in place in catalysts and particulate
filters.
[0044] In a second example, in the exemplary embodiment of FIG. 8,
an exhaust manifold 532 includes aluminum insulation 560 disposed
in the insulating void 48 between a housing 536 and the insulator
46. The housing 536 may include flanges 541 that are coupled in
close contact with outer peripheral surfaces of the insulator pipes
52 to provide a seal and prevent passage of exhaust gas between the
pipes 52 and the flanges 541. The aluminum insulation 560 may be of
multiple piece clamshell configuration, or may be a corrugated
foil, or a wrap, or the like. The aluminum insulation 560 may be
cast in place, assembled between housing portions, or introduced to
the void in any other suitable manner.
[0045] In a third example, in the exemplary embodiment of FIG. 9,
an exhaust manifold 632 includes ceramic ball insulation 660
disposed in the insulating void 48 between the insulator 46 and the
housing 36. The ceramic ball insulation 660 may be poured into the
void 48 after assembly or production of the housing 36 and the
insulator 46, or may be introduced to the void 48 in any other
suitable manner.
[0046] In a fourth example, in the exemplary embodiment of FIG. 10,
an exhaust manifold 732 includes aerogel insulation 760 disposed in
the insulating void 48 between the insulator 46 and the housing 36.
The aerogel insulation 760 may be poured into the void 48 after
assembly or production of the housing 36 and the insulator 46, or
may be introduced to the void 48 in any other suitable manner.
[0047] In the exemplary embodiment of FIG. 11, an exhaust manifold
832 includes the housing 36 having an exhaust flow insulator 846
coated to one or more interior surfaces of the housing 36. The
insulator 846 may include a ceramic coating that may be applied,
for example, by spraying, to a single housing, or to housing
portions that may be coated and then coupled together.
[0048] Referring to FIG. 12, the turbocharger turbine 34 may
include a housing 62 generally defining a path for exhaust gas. The
housing 62 may include an inlet 64 to receive exhaust gas, an
outlet 66 through which exhaust gas exits, and a volute 68 in fluid
communication therebetween. In one embodiment, the inlet 64 may
include a flange 70 that may be coupled in any suitable manner to
an upstream component, for example, a corresponding portion of the
collector 38 of the exhaust manifold housing 36 of FIG. 1. The
housing 62 may also include one or more liquid cooling passages
45a, 45b that may be supplied with coolant, for example, from an
engine in any suitable manner. The turbine 34 may be high pressure
turbine, low pressure turbine, and may be in any of various
arrangements to another turbine (not shown), for example, in
parallel, sequential, or switchable parallel-sequential
arrangements. An example of a multi-stage turbocharging arrangement
is disclosed in U.S. Patent Application Publication 2006/0137343,
which is assigned to the assignee hereof and incorporated by
reference in its entirety.
[0049] The turbine 34 may also include an exhaust flow insulator 72
carried in the exhaust gas path generally defined by the housing,
so as to convey exhaust gas through the insulator 72 and limit heat
transfer from the exhaust gas to the housing 62. The insulator 72
may define one or more insulating voids 74 between the insulator 72
and the housing 62 to further limit heat transfer from the exhaust
gas to the housing 62 and minimize or eliminate direct contact of
exhaust gas with the housing 62. Like the housing 62, the insulator
72 may include an inlet 76 to receive exhaust gas, an outlet 78
through which exhaust gas exits, and a volute 80 in fluid
communication therebetween.
[0050] As shown in FIG. 12, the insulator 72 may be constructed in
any suitable manner, for example, stamped from two or more
individual components 72a, 72b, which may be attached at a seam 82.
The seam 82 may include opposed flanges 82a, 82b, which may be
welded, crimped, fastened, and/or the like. The insulator component
72a may extend from an axially inboard shoulder 69 of the volute
68, in corresponding conformity to the internal surface of the
volute 68, to the seam 82. The other insulator component 72b may
extend from the seam 82, in corresponding conformity to the
internal surface of the volute 68, to the outlet 78.
[0051] Similarly, the housing 62 may include a plurality of
portions coupled together. For example, the housing 62 may be of a
clamshell configuration wherein one housing portion 62a is coupled
to another housing portion 62b, for example, by fastening opposed
flanges 63a, 63b to one another. In this embodiment, the insulator
72 may be placed in a first one of the housing portions 62a and
then another of the housing portions 62b may be assembled over the
insulator 72 and coupled to the first housing portion 62a in any
suitable manner so as to capture the insulator 72 in the housing
62.
[0052] In contrast, in the exemplary embodiment of a turbine 134
shown in FIG. 13, the housing 162 is cast around an exhaust flow
insulator 172 in any suitable manner. For example, the insulator
172 may be positioned in a die cavity (not shown), and then molten
material of the housing 162 may be introduced into the mold cavity
around the insulator 172 and cooled, to at least partially envelop
the insulator 172 in the cast housing 162 and to define an
insulating void 174. The insulator 172 may be produced from
multiple portions as described above with respect to FIG. 12, or
may be produced from a single component. For example, the insulator
172 may be spin-formed, flow formed, bent, axially compressed from
thin tube stock, or the like. The insulator component 172 may
extend from an axially inboard shoulder 169 of a volute 168, in
corresponding conformity to the internal surface of the volute 168,
to an outlet 178.
[0053] In the exemplary embodiment of FIG. 14, a turbine 234 may
include an exhaust flow insulator 272 having one or more apertures
284 to communicate some exhaust gas from the interior of the
insulator 272 to an insulating void 274 between the insulator 272
and the housing 162. The apertures 284 allow for heat expansion and
gas exchange between the two aforementioned spaces. As shown, the
apertures 284 may be provided in volute and outlet portions of the
insulator 272. But the apertures 284 also or instead may be
provided in an inlet portion of the insulator 272.
[0054] In the exemplary embodiment of FIG. 15, a turbine 334
includes a vacuum vented housing 362, which may be provided with a
vacuum vent passage 386 in fluid communication at one end with an
insulating void 374 of the turbine 334 and at another end with a
vacuum vent passage in an engine (not shown). The engine vacuum
vent passage may be in fluid communication with any suitable source
of engine vacuum, for example, an engine crankcase chamber (not
shown) via a check valve C shown schematically. The turbine 334 may
include openings between the housing 362 and the insulator 172 at
inlets 364, 376 and outlets 366, 378 thereof. Accordingly, hot air
or exhaust gas may be drawn through the insulating void 374 so as
to cool the housing 362.
[0055] In the various exemplary embodiments of FIGS. 16 through 19,
various examples of insulation materials are disposed in insulating
voids between insulators and exhaust manifold housings.
[0056] In a first example, in the exemplary embodiment of FIG. 16,
a turbine 434 includes a fiber insulation material 488 disposed in
the insulating void 174 between the housing 162 and the insulator
172. The fiber insulation material 488 may be cast in place,
assembled between housing portions, blown into the insulating void
172 in any suitable manner, or introduced to the void 172 in any
other suitable manner.
[0057] In a second example, in the exemplary embodiment of FIG. 17,
a turbine 534 includes aluminum insulation 588 disposed in the
insulating void 174 between the housing 162 and the insulator 172.
The aluminum insulation 588 may be of multiple piece clamshell
configuration, or may be a corrugated foil, or a wrap, or the like.
The aluminum insulation 588 may be cast in place, assembled between
housing portions, or introduced to the void in any other suitable
manner.
[0058] In a third example, in the exemplary embodiment of FIG. 18,
a turbine 634 includes ceramic ball insulation 688 disposed in the
insulating void 174 between the insulator 172 and the housing 162.
The ceramic ball insulation 688 may be poured into the void 174
after assembly or production of the housing 162 and the insulator
172, or may be introduced to the void 174 in any other suitable
manner.
[0059] In a fourth example, in the exemplary embodiment of FIG. 19,
a turbine 734 includes aerogel insulation 788 disposed in the
insulating void 174 between the insulator 172 and the housing 162.
The aerogel insulation 788 may be poured into the void 174 after
assembly or production of the housing 162 and the insulator 172, or
may be introduced to the void 174 in any other suitable manner.
[0060] In the exemplary embodiment of FIG. 20, a turbine 834
includes the housing 162 having an exhaust flow insulator 872
coated to one or more interior surfaces of the housing 162. The
insulator 872 may include a ceramic coating that may be applied to
a single housing, or to housing portions that may be coated and
then coupled together.
[0061] In the various embodiments, the insulators may be disposed
adjacent to the housings over substantial portions of the internal
surface areas of the housings that would be otherwise exposed to
exhaust gas. However, 100% coverage of the insulators to the
housings in the areas of the exhaust gas passages may not be
necessary or even feasible due to cost constraints. Instead, the
insulators may be selectively applied to those locations where
shielding or insulating is desired and cost effective. However,
greater than 50% of the surface areas may be covered to reduce the
amount of heat transfer from the exhaust gas to the housings to a
degree sufficient to prevent damage to the housings or unacceptable
performance of the respective device, and/or to reduce quantity
and/or volume of liquid cooling passages in the housings. For
example, it is anticipated that such a configuration may result in
a 1/3 to 2/3 volumetric reduction in liquid cooling of an exhaust
system device housing.
[0062] Similarly, the insulation material may be disposed between
the housings and the insulators over substantial portions thereof.
But 100% coverage of the insulation material over the portions of
the housings and insulators that correspond to the exhaust gas
passages may not be necessary or even feasible due to cost
constraints. Instead, the insulation material may be selectively
applied to those locations where shielding or insulating is desired
and cost effective.
[0063] Likewise, the cooling passages may be disposed in the
housings over substantial portions thereof. But 100% coverage of
the cooling passages over the portions of the housings and
insulators that correspond to the exhaust gas passages may not be
necessary or even feasible due to cost constraints. Instead, the
cooling passages may be selectively applied to those locations
where cooling is desired and cost effective. For example, in areas
with otherwise good thermal insulation, liquid cooling passages may
be avoided or eliminated in favor of convective air cooling.
[0064] Another exemplary embodiment includes an exhaust system
device that may comprise a liquid-cooled non-ferrous housing
including an inlet, an outlet, a path for exhaust gas between the
inlet and the outlet, and a liquid cooling passage adjacent the
exhaust gas path, and that also may comprise a ferrous exhaust flow
insulator carried in the exhaust gas path of the housing
substantially from the inlet and substantially to the outlet and
for conveying exhaust gas through the housing to limit heat
transfer from exhaust gas to the housing.
[0065] The housing may include an exhaust manifold housing.
[0066] The housing may include a turbocharger turbine housing.
[0067] At least a portion of the insulator may be applied in direct
contact with the housing.
[0068] At least a portion of the insulator may be a coating.
[0069] The coating may be ceramic.
[0070] The insulator may be comprised of multiple portions.
[0071] The multiple portions may include flanges coupled to one
another along a seam.
[0072] The housing may be cast from aluminum and the insulator may
be manufactured from steel.
[0073] The housing may be cast around the insulator.
[0074] The housing may be comprised of multiple portions coupled
together.
[0075] The housing may be of a clamshell configuration having one
housing portion coupled to another housing portion.
[0076] An insulating void may be between the insulator and the
housing.
[0077] The insulator may include apertures to communicate exhaust
gas from the interior of the insulator to the insulating void
between the insulator and the housing.
[0078] The insulating void may be vacuum vented by a vacuum vent
passage in the housing in fluid communication at one end with the
insulating void and communicable at another end with a vacuum vent
passage in an engine.
[0079] Insulation material may be disposed in the insulating void
between the insulator and the housing.
[0080] The insulation material may be at least one of cast in
place, poured into the insulating void, assembled between portions
of the housing, or blown into the insulating void.
[0081] The insulation material may include fiber insulation.
[0082] The insulation material may include aluminum insulation.
[0083] The insulation material may include ceramic ball insulation
ball insulation.
[0084] The insulation material may include aerogel insulation.
[0085] A further exemplary embodiment includes an exhaust manifold
that may comprise a liquid-cooled non-ferrous housing including an
inlet, an outlet, a path for exhaust gas between the inlet and the
outlet, and a liquid cooling passage adjacent the exhaust gas path,
and that also may comprise a ferrous exhaust flow insulator carried
in the exhaust gas path of the housing substantially from the inlet
and substantially to the outlet and for conveying exhaust gas
through the housing to limit heat transfer from exhaust gas to the
housing, and that further may comprise an insulation material
disposed between the housing and the insulator.
[0086] An additional exemplary embodiment includes an engine
turbocharger turbine that may comprise a liquid-cooled non-ferrous
turbine housing including a liquid cooling passage defining a path
for exhaust gas, and that also may comprise an exhaust flow
insulator carried in the exhaust gas path of the housing to convey
exhaust gas through the housing, and defining an insulating void
between the insulator and the housing to limit heat transfer from
exhaust gas to the housing.
[0087] Yet another exemplary embodiment includes an exhaust system
device that may comprise a liquid-cooled non-ferrous housing
including an inlet, an outlet, a path for exhaust gas between the
inlet and the outlet, and a liquid cooling passage adjacent the
exhaust gas path, and that also may comprise an exhaust flow
insulator coated to the housing along the exhaust gas path of the
housing substantially from the inlet and substantially to the
outlet and for conveying exhaust gas through the housing to limit
heat transfer from exhaust gas to the housing.
[0088] The above description of embodiments is merely exemplary in
nature and, thus, variations thereof are not to be regarded as a
departure from the spirit and scope of the invention.
* * * * *