TECHNICAL FIELD
The present disclosure relates to an exhaust manifold having a water jacket, and more particularly, to an engine exhaust manifold having a water jacket with shielded cooling.
BACKGROUND
During operation of an internal combustion engine, the exhaust manifold becomes very hot due to internal passage of hot exhaust gas exiting cylinders of the engine through an associated cylinder head, which is coupled to the exhaust manifold. As a result, water jackets have been provided on an exterior surface of exhaust manifolds. For example, a water-jacketed exhaust manifold for use in a marine engine is disclosed in U.S. Pat. No. 5,148,675 to Inman (“the '675 patent”). In particular, the '675 patent discloses a water jacketed header pipe connectable to a face of the exhaust manifold of the engine. The header pipe is cast to define water jacket spaces through which cooling water can flow. Openings are provided through the walls of the header pipe to the water jacket spaces, so that pipes can be connected to the header pipe to introduce cooling water into the water jacket spaces.
SUMMARY
In one aspect, the present disclosure includes an exhaust manifold configured to be coupled to a cylinder head of an internal combustion engine. The exhaust manifold includes a manifold section, and the manifold section includes a manifold tube configured to receive exhaust gas from the cylinder head, and a water jacket tube at least partially defining a tube configured to receive cooling fluid. The manifold tube is received in the water jacket tube. The manifold section further includes a support in a gap between the manifold tube and the water jacket tube, and an adaptor tube coupled to the water jacket tube and configured to provide flow communication between the cylinder head and the manifold tube.
According to a further aspect, the present disclosure includes an exhaust manifold configured to be coupled to a cylinder head of an internal combustion engine. The exhaust manifold includes a first manifold section and a second manifold section, and the first manifold section includes a manifold tube configured to receive exhaust gas from the cylinder head, and a water jacket tube at least partially defining a tube configured to receive cooling fluid. The manifold tube is received in the water jacket tube. The first manifold section further includes a support in a gap between the manifold tube and the water jacket tube, and an adaptor tube coupled to the water jacket tube and configured to provide flow communication between the cylinder head and the manifold tube. The first and second manifold sections are coupled to one another.
According to another aspect, the disclosure includes an internal combustion engine including a cylinder block defining a cylinder, a cylinder head coupled to the cylinder block, and an exhaust manifold coupled to the cylinder head. The cylinder head provides flow communication between the cylinder and the exhaust manifold. The exhaust manifold includes a manifold section, and the manifold section includes a manifold tube configured to receive exhaust gas from the cylinder head, and a water jacket tube at least partially defining a tube configured to receive cooling fluid. The manifold tube is received in the water jacket tube. The manifold section further includes a support in a gap between the manifold tube and the water jacket tube, and an adaptor tube coupled to the water jacket tube and configured to provide flow communication between the cylinder head and the manifold tube.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic perspective view of an exemplary embodiment of an internal combustion engine including an exemplary embodiment of an exhaust manifold.
FIG. 2 is a schematic, partial cross-section view of a portion of the exemplary exhaust manifold shown in FIG. 1.
FIG. 3 is a schematic, partial cross-section view of a portion of the exemplary exhaust manifold shown in FIG. 1.
FIG. 4 is a schematic, partial cutaway view of a portion of the exemplary exhaust manifold shown in FIG. 1.
DETAILED DESCRIPTION
FIG. 1 is a schematic perspective view of an exemplary embodiment of an internal combustion engine 10. Exemplary engine 10 includes a cylinder block 12 extending along a longitudinal axis X between opposite ends 12a and 12b of engine 10. Cylinder block 12 defines a number of cylinders 14 therein. For example, in the exemplary configuration of engine 10 shown in FIG. 1, cylinder block 12 defines two rows of eight longitudinally-spaced cylinders 14, resulting in a V-16 engine configuration. Other engine configurations known to those skilled in the art are contemplated, such as, for example, in-line configurations including a single row of longitudinally-spaced cylinders 14, and configurations having more than two rows of longitudinally-spaced cylinders (e.g., three rows). In addition, engine 10 may include fewer or more cylinders 14 in each row, such as, for example, two, three, four, five, six, seven, nine, ten, eleven, twelve, or more cylinders 14 per row, resulting in V-4, V-6, V-8, V-10, V-12, V-14, V-18, V-20, V-22, and V-24 configurations. Engine 10 may be a compression-ignition engine, spark-ignition engine, homogeneous-charge compression ignition engine, a two-stroke engine, a four-stroke, or any type of internal combustion engine known to those skilled in the art.
Exemplary engine 10 also includes a cylinder head 16 for providing intake and exhaust flow communication with cylinders 14 of each row. According to the exemplary embodiment shown in FIG. 1, each cylinder head 16 includes a number of cylinder head modules 18 corresponding to the number of cylinders 14 defined by cylinder block 12. It is contemplated that each cylinder head module 18 may serve to provide flow communication with more than one cylinder 14, for example, two, three, or four cylinders 14. Cylinder head modules 18 may be configured to be decoupled individually from cylinder block 12, thereby permitting removal of a single cylinder head module 18, without necessarily removing any other cylinder head modules 18. This exemplary configuration may serve to simplify maintenance of engine 10, as explained in more detail below.
As shown in FIG. 1, exemplary engine 10 includes an exhaust manifold 20 coupled to each cylinder head 16 to provide flow communication between exhaust ports of cylinder head 16 and the surroundings. Exemplary engine 10 includes four turbochargers 22 located generally at one longitudinal end of engine 10 (e.g., the opposite end 12b of engine 10). For example, two turbochargers 22 may be associated with each row of cylinders 14. Other numbers of turbochargers 22 are contemplated. According to some embodiments, engine 10 may not have any turbochargers. In the exemplary embodiment shown, exhaust manifolds 20 extend along the longitudinal length of engine 10 and provide flow communication between cylinder heads 16 and turbochargers 22.
As shown in FIG. 1, each exemplary exhaust manifold 20 includes a plurality of manifold sections 24 coupled to one another in end-to-end fashion along the longitudinal length of engine 10. According to some embodiments, manifold sections 24 may have a substantially circular cross-section, although other cross-sections are contemplated. In the example shown, a manifold section 24a located at an end of exhaust manifold 20 opposite turbochargers 22 includes an end cap 26 (e.g., a removable end cap) preventing flow communication between exhaust manifold 20 and the surroundings via manifold section 24a. At an end of exhaust manifold 20 opposite manifold section 24a, a manifold section 24b is coupled to a riser manifold section 28 extending between manifold section 24b and turbochargers 22.
As shown in FIGS. 2 and 3, exemplary manifold sections 24 include a manifold tube 30 configured to receive exhaust gas from an exhaust port 32 of cylinder head module 18, and a water jacket tube 34 configured to receive cooling fluid. According to some embodiments, manifold tube 30 and/or water jacket tube 34 may have a substantially circular cross-section, although other cross-sections are contemplated. Manifold tube 30 is received in water jacket tube 34, and a support 36 between manifold tube 30 and water jacket tube 34 provides a gap 38 between manifold tube 30 and water jacket tube 34. Gap 38 provides an insulation shield between the outer surface of manifold tube 30 and water jacket tube 34, and gap 38 may contain a fluid, such as, for example, air and/or another gas. Support 36 shown in FIG. 2 defines an annular ring, with manifold tube 30 being received in the annular ring and manifold tube 30 and support 36 being received in water jacket tube 34. According to some embodiments, support 36 includes a longitudinally extending portion 39 and a radially extending flange 40 spacing manifold tube 30 from water jacket tube 34. Radially extending flange 40 may include sections circumferentially spaced from one another, which may serve to align support 36 between manifold tube 30 and water jacket tube 34, reduce fretting, and/or reduce a conduction path between manifold tube 30 and water jacket tube 34. According to some embodiments, support 36 may be secured to manifold tube 30 via, for example, adhesives and/or welding.
Exemplary manifold section 24 also includes an adaptor tube 42 coupled at one end to water jacket tube 34 and at an opposite end to cylinder head module 18. Adaptor tube 42 is configured to provide flow communication between exhaust port 32 of cylinder head module 18 and manifold tube 30 of manifold section 24. As shown in FIGS. 2 and 3, adaptor tube 42 includes at one end a flange 44 configured to be coupled to a cylinder head module 18 and at an opposite end a tube portion 46 configured to provide flow communication between exhaust port 32 and manifold tube 30. The exemplary embodiment of exhaust manifold 20 shown in FIG. 2 includes two adaptor tubes 42 coupled to manifold section 24. However, it is contemplated that fewer or more adaptor tubes 42 may be coupled to an individual manifold section 24. According to some embodiments, a manifold adaptor 45 may be provided between flange 44 of adaptor tube 42 and cylinder head module 18, as shown in FIGS. 2 and 3. Manifold adaptor 45 may serve as a heat sink for heat from exhaust gas exiting exhaust port 32, and may serve as a spacer between flange 44 and cylinder head module 18.
In the exemplary embodiment shown in FIGS. 2 and 3, water jacket tube 34 includes a water jacket tube wall 48 extending along a longitudinal axis of manifold section 24, and water jacket tube wall 48 defines two water jacket wall apertures 50. In the exemplary embodiment shown, water jacket tube wall 48 includes an inner tubular portion 52a and an outer tubular portion 52b separated from one another to define therebetween passages 54 configured to receive cooling fluid, such as, for example, water and/or coolant (e.g., a glycol-based coolant). For example, cylinder block 12 may define water jacket passages (not shown) for circulating engine coolant, and the water jacket passages of engine 10 and passages 54 of water jacket tube 34 may be configured to be in flow communication with one another, so that engine coolant may be received in passages 54 of water jacket tube 34. Flange 44 of adaptor tube 42 and water jacket tube wall 48 are configured to provide a seal between adaptor tube 42 and water jacket tube 34, so that fluid and/or exhaust gas is prevented from escaping between adaptor tube 42 and water jacket tube 34. According to some embodiments, water jacket tube 34 and/or adaptor tube 42 may be formed of aluminum or other suitable material.
Adaptor tube 42 may be secured to water jacket tube 34 via, for example, removable fasteners such as bolts, adhesives, and/or welding. In embodiments having a manifold adaptor 45, manifold adaptor 45 may be secured to water jacket tube 34 via the same fasteners as flange 44 of adaptor tube 42. According to some embodiments, manifold section 24 may be secured to cylinder head module 18 via removable fasteners such as bolts, with the fasteners extending from a side of water jacket tube 34 opposite cylinder head module 18, into threaded bores (not shown) in cylinder head module 18.
By virtue of this exemplary configuration, it may be possible to perform maintenance associated with one cylinder 14 more easily relative to an engine that includes a unitary cylinder head that serves as the cylinder head for an entire row of cylinders. Thus, it may not be necessary to remove the entire exhaust manifold 20. Rather, a manifold section 24 associated with the cylinder 14 being serviced may be removed without removing additional manifold sections 24. According to some embodiments, an individual cylinder head module 18 may be removed without removing any of manifold sections 24. For example, fasteners coupling a manifold section 24 to an associated cylinder head module 18 may be removed without removing the manifold section 24, and the cylinder head module 18 may be removed from cylinder block 12 by removing fasteners coupling the cylinder head module 18 to cylinder block 12.
In some embodiments, manifold adaptor 45 may not be secured to manifold section 24, as described above. Rather, manifold adaptor 45 may be sandwiched between flange 44 of adaptor tube 42 and cylinder head module 18, and held in place via the fasteners that secure manifold section 24 to cylinder head module 18.
As shown in FIGS. 2 and 3, exemplary manifold tube 30 includes a manifold tube wall 56 extending along a longitudinal axis of manifold section 24, and manifold tube wall 56 defines two manifold tube apertures 58 configured to receive an end of adaptor tube 42. Manifold tube wall 56 includes flanges 60 extending outwardly around respective manifold tube apertures 58 toward cylinder head modules 18. As shown, adaptor tubes 42, manifold tube apertures 58, and flanges 60 are configured to provide clearance 62 between adaptor tubes 42 and flanges 60. Clearance 62 may serve to reduce wear between adaptor tube 42 and manifold section 24. Clearance 62 may provide flow communication between associated adaptor tube 42 and gap 38 provided between manifold tube 30 and water jacket tube 34. This may permit some exhaust gas to flow from adaptor tubes 42 into gap 38. However, because water jacket tube 34 is sealingly engaged with flanges 44 of adaptor tubes 42, exhaust gas is prevented from escaping exhaust manifold 20. According to some embodiments, manifold tube 30 is formed from stainless steel or other suitable material.
As shown in FIG. 2, exemplary water jacket tubes 34 include a first connecting flange 64a at one longitudinal end of water jacket tube 34 and a second connecting flange 64b at the opposite longitudinal end of water jacket tube 34. For example, first connecting flange 64a defines a first shoulder 66a and second connecting flange 64b defines a second shoulder 66b. As shown in FIG. 2, a first manifold section 24′ is coupled to a second manifold section 24″ via first and second connecting flanges 64a and 64b, with first and second shoulders 66a and 66b serving to engage one another. Connecting flanges 64a and 64b may be coupled to one another via bolts, other fasteners, adhesives, and/or welding.
Exemplary manifold tubes 30 include a first end 68a at one longitudinal end of manifold tube 30 and a second end 68b at the opposite longitudinal end of manifold tube 30. A first end 68a of a first manifold section 24′ and a second end 68b of a second manifold section 24″ are configured to be coupled to one another to provide a slip joint, for example, where the inner surface of first end 68a fits around an outer surface of second end 68b. According to some embodiments, first and second ends 68a and 68b may be secured to one another via adhesives and/or welding. According to some embodiments, first and second ends 68a and 68b may be coupled to one another without the use of fasteners, adhesives, and/or welding. This may render it easier to assemble and disassemble adjacent manifold sections 24′ and 24″, for example, independently of one another.
As shown in FIG. 1, riser manifold section 28 is coupled to manifold section 24b and provides flow communication between manifold section 24b and a pair of turbochargers 22. As shown in FIGS. 3 and 4, riser manifold section 28 includes a flange 70 configured to be coupled to flange 64b of manifold section 24b via, for example, bolts, other fasteners, adhesives, and/or welding.
As shown in FIGS. 3 and 4, exemplary riser manifold section 28 includes a riser housing 72. As shown in FIG. 3, riser housing 72 includes a riser water jacket 73 (e.g., within the walls of riser housing 72), with riser water jacket 73 being in flow communication with a water jacket tube 34 of manifold section 24b. According to some embodiments, riser housing 72 may be formed from aluminum or another suitable material. Riser manifold section 28 also includes a riser manifold tube 74 in flow communication with manifold tube 30 of manifold section 24b, with riser manifold tube 74 being received in riser housing 72. According to some embodiments, riser manifold tube 74 may be formed from stainless steel or another suitable material. A number of spacers 76 (FIG. 4) extend across a gap 38a between riser housing 72 and riser manifold tube 74, thereby providing an insulation shield between the outer surface of riser manifold tube 74 and riser housing 72, and gap 38a may contain a fluid, such as, for example, air and/or another gas.
In the exemplary embodiment shown in FIG. 4, engine 10 includes four turbochargers 22, with two turbochargers 22 in flow communication with each exhaust manifold 20. Thus, exemplary riser manifold section 28 includes a riser manifold tube 74 having a Y-section 78, with each branch of the Y extending to one of the two turbochargers 22.
INDUSTRIAL APPLICABILITY
Exemplary engine 10 may be used to supply mechanical power to various machines, including, for example, pumps, compressors, generators, and vehicles. For example, engine 10 may be used in marine applications, such as to propel a boat or ship, or in oil exploration or drilling applications. In such applications, it may be desirable to provide an engine having an exhaust manifold that does not exceed a specified surface temperature, such as, for example, 200 degrees C.
According to some embodiments, exhaust manifold 20 may provide exhaust manifold surface temperatures below, for example, 200 degrees C. Gap 38 between manifold tube 30 and water jacket tube 34 provides an insulation shield between the outer surface of manifold tube 30 and water jacket tube 34. Gap 38 may contain a fluid, such as, for example, air and/or another gas, which reduces conduction between the outer surface of manifold tube 30 and water jacket tube 34. In addition, support 36 provides a reduced conduction path between manifold tube 30 and water jacket tube 34. As result, relative to exhaust manifolds having a water jacket but no gap between a tube conveying exhaust gas and the water jacket, exemplary exhaust manifold 20 may provide reduced exhaust manifold surface temperatures. In addition, by virtue of gap 38 serving to reduce heat transfer between manifold tube 30 and water jacket tube 34, a cooling system having a reduced capacity may be used while still meeting cooling requirements necessary to maintain the exhaust manifold surface temperature below a desired maximum. For example, it may be possible to use smaller radiators, lower capacity coolant pumps, and/or less coolant.
According to some embodiments, exhaust manifold 20 may provide flexibility of application and ease of service by virtue of including manifold sections 24. For example, manifold sections 24 may be dimensioned so that they may be assembled to provide an exhaust manifold for a number of engine configurations. For example, in the example shown in FIG. 1, engine 10 has a V-16 configuration, and each exhaust manifold 20 includes four manifold sections 24, with each manifold section 24 providing flow communication with two cylinder head modules 18. In a similar manner, exemplary sections 24 could be used to make up an exhaust manifold for a V-12 engine configuration, with each exhaust manifold including three manifold sections 24 instead of four. In addition, five exemplary manifold sections 24 could be used to form each exhaust manifold of an engine having a V-20 configuration.
For engines such as exemplary engine 10, which includes separate cylinder head modules 18 associated with each cylinder 14, exemplary exhaust manifold 20 may facilitate ease of service or maintenance for engine 10. For example, with individual cylinder head modules, it may be possible to perform maintenance associated with one cylinder 14 without removing an entire unitary cylinder head that serves as the cylinder head for an entire row of cylinders. In such a situation, it may not be necessary to remove the entire exhaust manifold 20. Rather, a manifold section 24 associated with the cylinder being serviced may be removed without removing additional manifold sections. According to some embodiments, an individual cylinder head module 18 may be removed without removing any of manifold sections 24 for exhaust manifold 20. For example, fasteners coupling a manifold section 24 to an associated cylinder head module 18 may be removed without removing the manifold section 24, and the cylinder head module 18 may be removed from cylinder block 12 by removing fasteners coupling the cylinder head module 18 to cylinder block 12.
It will be apparent to those skilled in the art that various modifications and variations can be made to the exemplary disclosed engine, exhaust systems, and related methods. Other embodiments will be apparent to those skilled in the art from consideration of the specification and practice of the exemplary disclosed embodiments. It is intended that the specification and examples be considered as exemplary only, with a true scope being indicated by the following claims and their equivalents.
Patent Application
20130000287
