WO2015140210A1

WO2015140210A1 - Manifold

Info

Publication number: WO2015140210A1
Application number: PCT/EP2015/055680
Authority: WO
Inventors: Steffen Kauffmann; Markus Geminn; Andreas Steigert
Original assignee: Tenneco Gmbh
Priority date: 2014-03-20
Filing date: 2015-03-18
Publication date: 2015-09-24
Also published as: CN106103930A; US20170051655A1

Abstract

The invention relates to a manifold system (1) for an internal combustion engine, comprising a housing (2) designed as a collecting manifold, which housing has two inlet openings (20, 21) and an outlet opening (24) for connecting two outlets of an internal combustion engine to an exhaust gas system in regard to flow and at least one connection opening (22, 23) provided on the housing for connecting to an outer shell of a double-shell air-gap-insulated manifold (30-33), and comprising at least one air-gap-insulated manifold connected to the connection opening, which air-gap-insulated manifold has an inner shell (34) having an inlet opening (36) for connecting to an outlet of the internal combustion engine in regard to flow and having an outer shell (35), wherein all air-gap-insulated manifolds are completely formed from sheet metal and are structurally or geometrically identical and, on the housing, the size of a distance A2 between one of the two inlet openings and the outlet opening is between 30 mm and 300 mm or between 50 mm and 120 mm.

Description

elbow

The invention relates to a manifold system for an internal combustion engine having a manifold designed as a housing with two inlet openings and with an outlet opening for strömungsstechni- see connection of two outlets of an internal combustion engine with an exhaust system. On the housing a connection opening for connection to an outer shell of a double-shell LSI manifold is provided. At least one LSI manifold is connected to the connection opening, which has an inner shell with an inlet opening for the fluidic connection with in each case one outlet of the internal combustion engine and with an outer shell.

An inlet opening, outlet opening or connection opening is to be understood as the respective end of a pipe or of a housing which is connected by means of further connecting means, such as, for example, flanges or weld metal, to a further, other component.

It is already known from EP 1 914 401 A2 designed as manifold manifold housing for an internal combustion engine with multiple exhaust ducts, one of which a Abgaseinlassöffnung end having each connectable to an outlet of the internal combustion engine and the other end is in each case connected to a exhaust outlet opening having a collecting device , At least one exhaust gas guide is from the outlet of the internal combustion engine to the collecting device as a casting and at least one other exhaust gas guide is formed from the outlet of the internal combustion engine to the collecting device as a built pipe or shell part. DE 39 25 802 A1 describes the connection of two outlets of the internal combustion engine with an exhaust system, a casting, which serves as an adapter for two manifold pipes. The connection of further outlets with the exhaust system via separate manifold pipes, which are not connected to the casting. According to DE 103 01 395 A1 a designed as manifold manifold double-walled housing is known in which the outer shell directly connects all the outlets of the internal combustion engine together.

The present invention has for its object to further develop an exhaust system such that the sound of the exhaust noise and thus the exhaust system is optimized over several important speed ranges of the engine. Each engine has individual optimum operating points, in which the complex relationship between torque and consumption is advantageous. Such optimal operating points can be found in relatively narrow speed ranges, so that the approach is designed to acoustically develop the exhaust system in relation to these relevant engine speed ranges.

The object is achieved according to the invention in that all LSI manifold completely formed from sheet metal, identical or geometrically identical and that the housing the degree of the distance between one of the two inlet openings and the outlet opening between 30 mm and 300 mm or between 50 mm and 120 mm.

Due to the identical design of the LSI manifold connected to the manifold or to the housing, acoustics between the outlet and the manifold are achieved, in particular in the case of 6-cylinder in-line engines, which sounds more harmonious than known manifold systems. This improvement is particularly advantageous when there is a certain amount of distance between one of the two inlet openings and the outlet opening, which varies between 50 mm and 120 mm, depending on the model of the manifold system. It was found that at smaller distances with the advantage of a small size, the sound behavior is extremely affected even with minor changes in the distances. An increase in the distance, however, causes advantageous sound properties. Such manifold systems are preferably used in truck diesel engines or stationary diesel engines in which a turbocharger is subsequently arranged on the manifold. The designed as a central and bearing part housing provides the necessary statics for the connection of the turbocharger with the outlets on the motor housing.

For this purpose, it is particularly advantageous if the distance is dimensioned as a function of sound waves of the exhaust gas whose sound wavelength is calculated by n ^* A2 or 1 / n * A2, where n is an element of the natural numbers, but not zero. Here, A2 is the above-described measure of the distance between one of the two inlet openings and the outlet opening. L is the mean physical sound wave length, which is calculated from the quotient of propagation velocity C [m / s = meter / second] of the sound in the exhaust gas to the frequency f [1 / s = 1 / second = heart] of the wave. At an exhaust gas temperature of 700 ° C and a frequency of 300 Herz [Hz] results in a wavelength of about 750 mm. For example, this 300 Hz signal is generated by a 6-cylinder machine at 3000 rpm [rpm]. This low-frequency signal would be highlighted at a distance of 1/10 of the wavelength, ie with a distance A2 of 75 mm in the housing. It can also be advantageous for this purpose if the two inlet openings within the housing are fluidically and acoustically in exchange with each other, whereby the harmonization is further increased, because a dynamic compensation can be done within the housing.

Furthermore, it may be advantageous if the two inlet openings in the housing are separated by a channel wall and two through the channel wall

Flow channels are formed, wherein both flow channels open at the outlet opening at the end of the channel wall and the two flow channels via an opening provided upstream of the outlet opening in the channel wall opening or perforation fluidically and acoustically in exchange. As a result, the properties of an absolute group separation without any acoustic and fluid dynamic interaction between the two manifold areas adjoining the flow channels coupled with the properties without group separation with full acoustic and flow dynamic interaction. The opening or perforation provided in the channel wall reduces the flow dynamic interaction, but at the same time the acoustic interaction remains largely intact. The measure of the acoustic interaction varies both with the distance between one of the two inlet openings and the outlet opening and with the speed, because depending on the size of the opening as a forced leakage, the interaction decreases with increasing speed.

It may also be advantageous if the opening or the perforation has a total cross section of between 25 mm ² and 50 mm ² .

It may advantageously be provided that the manifold or the housing is formed as a one-piece casting. The vibration behavior of a casting is, as far as the acoustics of manifolds, compared to that of a sheet metal part very beneficial.

Of particular importance may be for the present invention, when the manifold is formed from a low-alloyed gray cast iron having a carbon content of at least 1.00% by mass and further alloying additions with a respective average content of at most 50.00% by mass. Such called gray cast iron materials have an advantageous acoustic vibration behavior.

Alternatively, it may be advantageous if the housing is formed completely from sheet metal, multi-part and double-walled and formed with air gap insulation with an outer housing and an inner housing, wherein the connection opening is provided on the outer housing. The acoustic disadvantages of the sheet metal material can be compensated by a special shape of the outer housing. It is also advantageous if the LSI manifold has a connection opening and an outlet opening, wherein the LSI manifold is connected with its connection opening directly to the manifold and connected via its outlet opening to the connection opening of a further LSI manifold. This allows both sides of a manifold to connect only one LSI manifold and two LSI manifolds on both sides. The elbow system with two bends for a 4-cylinder internal combustion engine can be extended by two more identical sheet metal manifolds to a manifold system for a 6-cylinder engine.

For this purpose, it may be advantageous if the outlet opening of the outermost LSI bend is closed by a cover. The cover fits according to the system on each of the identical LSI manifold.

Furthermore, it may be advantageous if the LSI manifold is connected to the manifold manifold by welding or soldering or gluing. In particular, the welded joint in a manifold made of gray cast iron offers a very simple and inexpensive production method. It may also be advantageous, for reasons of flexible mounting, that the LSI manifold is connected in a form-fitting manner to the collector manifold with a union nut or with a V-band clamp or with a flange connection or with a tensioning element.

Further, it may be advantageous if the manifold only has a connection opening, are connected via the middle or directly two LSI manifolds. This asymmetrical design has acoustic advantages over the symmetrical design in special applications.

Finally, it may be advantageous if the manifold connects the exhaust ports with a housing of a turbocharger and for this purpose forms a arranged between the engine block and the turbocharger supporting member. Further advantages and details of the invention are explained in the patent claims and in the description and illustrated in the figures. It shows:

Figure 1a is a sectional view of a manifold designed as a manifold

Housing with interacting flow channels;

Figure 1b is a side view of the manifold according to Figure 1a;

Figure 2 is a sectional view of a manifold manifold manifold manifold system having four LSI manifolds; Figure 3 is a sectional view of a manifold system having a manifold with interacting flow channels and two LSI manifolds;

Figure 4 is a manifold, double-walled sheet metal;

FIG. 5 shows a sectional view of a flange connection between manifold manifold and LSI manifold;

Figure 6 is a sectional view of a connection between the manifold and LSI manifold via an inlay in the manifold;

Figure 7a is a view of a manifold with arranged on both sides

V-band clamp; Figure 7b is a sectional view of a V-band clamp connection between

Manifold and LSI manifold;

Figure 8a is a schematic representation of the distance between a respective inlet opening and the outlet opening in a manifold in a view from above; 8b is a schematic representation of the distance between a respective inlet opening and the outlet opening in a manifold in a side view.

FIG. 1 a shows a sectional view of a housing 2 designed as a manifold, with interacting flow channels 25, 26. The housing 2 is formed from a gray cast iron and, in addition to two inlet openings 20, 21 for connecting the housing 2 to not shown outlets of an internal combustion engine also two connection openings 22, 23 for each LSI manifold 31, 32. From the two inlet openings 20, 21, two flow channels 25, 26, which are arranged next to one another and are partially separated by a channel wall 27, extend within the housing 2 as far as an outlet opening 24 of the housing 2 shown in FIG. 1b. To improve the acoustic properties of the manifold 2, two flow channels 25, 26 via an opening 271 in the channel wall 27 with each other in interaction.

In the embodiment of a manifold system 1 shown in Figure 2, the housing 2 is not symmetrical, but has as well as the embodiment of Figures 1a and 1b next to the two inlet ports 20, 21, two connection openings 23 for each LSI manifold 31, 32 , Of the two inlet openings 20, 21, two flow channels 25, 26 extend within the housing 2 to the outlet opening 24 of the housing 2. The two flow channels 25, 26 are here also partially separated by a channel wall 27 in their interaction. The illustrated with arrows average length of the two flow channels 25, 26 corresponds to one of the figures 8a and 8b in more detail

Distance A2 between the respective inlet opening 20, 21 and the outlet opening 24. In this embodiment, the distances A2 differ by a factor of 1.6.

FIG. 3 shows a housing 2 for a manifold system 1 for an internal combustion engine with four cylinders arranged in series. The housing 2 has only one connection opening 22 for an LSI manifold 30. In the case of sem housing 2 is no reduction in the interaction between the two flow channels 25, 26 provided by a channel wall 27.

In Figure 4, an air gap-insulated housing 2 is shown, which is designed as a manifold. The housing 2 has an outer housing 28 and two inner housings 29 integrated in the outer housing 28.

The housing 2 is designed as a supporting component and connects the outlets of the engine block, not shown, with a housing, not shown, of a turbocharger. To the housing 2 include on one or both sides of LSI manifold 30-33, which have no supporting or statically relevant function.

The illustrated in the two embodiments of Figures 2 and 3 LSI manifold 30-33 are formed from sheet metal and geometrically identical or identical. The shape equality of all LSI manifolds 30-33 improves the acoustic characteristics in the most important operating points of the internal combustion engine because the vibration and resonance behavior is identical in all LSI manifolds 30-33. A different shape would result in different vibration and resonance behavior.

In addition, the identical design has the advantage that in combination with a housing 2 formed as a manifold 2 for two outlets a manifold system 1 for a 4-cylinder internal combustion engine by two LSI manifolds 30, 33 supplemented for a 6-cylinder internal combustion engine can be used , In this case, the last LSI manifold 30, 33 in the row is closed by a cover 4. The connection between the LSI manifolds 30-33 and between the lid 4 and the respective LSI manifold 30, 33 is formed as a welded joint.

The identical LSI manifolds 30 have, as air-gap-insulated manifolds, an inner shell 34 and an outer shell 35 surrounding the inner shell 34. Both shells 34, 35 extend from a respective inlet opening 36 in the flow direction to a respective outlet opening 37 and opposite to the flow direction to a respective connection opening 38. At the respective openings 36-38 close the inner shell 34 and the outer shell 35 in one of the flow directions flush with each other.

When connecting the respective LSI manifold 30-33 to the housing 2, the outer shell 35 is decisive for the particular connection technology provided. The inner shell 34 is usually inserted only in the housing 2.

The connection between the housing 2 and the outer shell 35 of the respective LSI bend 31, 32 is preferably formed as a welded connection. Alternatively, a connection as flange 7 or inlay 8 or V-band clamp 6 is provided according to the figures 5-7b.

The distance A2 between the respective inlet opening 20, 21 and the outlet opening 24 illustrated in FIGS. 8a and 8b is also dependent on the size ratios of the respective diameters De of the inlet openings 20, 21 to the diameters Da of the outlet opening 24. For an optimal acoustic adaptation to the most important operating points of the internal combustion engine, in particular with respect to the speeds relevant for the most important load ranges, thus the distances A2, the diameter ratios De, Da and the construction similarity of the LSI manifold 30- 33 are relevant.

Claims

Patent claims

Manifold system (1) for an internal combustion engine

a) a housing (2) designed as a collecting manifold with two inlet openings (20, 21) and with an outlet opening (24) for the fluidic connection of two outlets of an internal combustion engine with an exhaust system

b) and at least one connection opening (22, 23) provided on the housing (2) for connection to an outer shell of a double-shell LSI elbow (30-33) and

c) at least one LSI manifold (30-33) connected to the connection opening (22, 23), with an inner shell (34) with an inlet opening (36) for fluidic connection to an outlet of the internal combustion engine and with an outer shell (35) ,

characterized in that

d) all LSI manifolds (30-33) are completely formed from sheet metal, have the same construction or are geometrically identical and

e) that on the housing (2) the dimension of a distance (A2) between one of the two inlet openings (20, 21) and the outlet opening (24) is between 30 mm and 300 mm or between 50 mm and 120 mm.

Manifold system (1) according to claim 1, characterized in that the distance (A2) is dimensioned depending on sound waves of the exhaust gas, the sound wavelength (L) of which is calculated by n ^* A2 or 1 / n * A2, where n is an element of the natural Numbers, but not zero.

Manifold system (1) according to claim 1 or 2, characterized in that the two inlet openings (20, 21) within the housing (2) communicate with one another in terms of fluid flow and acoustics.

Manifold system (1) according to one of the preceding claims, characterized in that the two inlet openings (20, 21) in the housing (2) are separated by a channel wall (27) and two flow channels (25, 26) are formed by the channel wall (27). are, wherein both flow channels (25, 26) open at the outlet opening (24) at the end of the channel wall (27) and the two flow channels (25, 26) via an opening (25) provided in the channel wall (27) upstream of the outlet opening (24). 271) or perforation interact fluidly and acoustically.

Manifold system (1) according to claim 4, characterized in that the opening (271) or the perforation has a total cross section of between 25 mm ² and 50 mm ² .

Manifold system (1) according to one of the preceding claims, characterized in that the housing (2) is designed as a one-piece casting.

Manifold system (1) according to claim 6, characterized in that the housing (2) is formed from a low-alloy gray cast iron with a carbon content of at least 1.00 mass% and further alloy additives with a respective average content of a maximum of 50.00 mass% is.

Manifold system (1) according to one of claims 1 to 4, characterized in that the housing (2) is formed entirely from sheet metal, is multi-part and double-walled and air-gap insulated with an outer housing (28) and at least one inner housing (29), the connection opening (22, 23) is provided on the outer housing (28).

9. Manifold system (1) according to claim 8, characterized in that the LSI manifold (30-33) has an outlet opening (37) and a connection opening (38), the LSI manifold (31, 32) with its connection opening ( 38) is connected directly to the housing (2) and is connected via its outlet opening (37) to the connection opening (38) of a further LSI elbow (30, 33).

10. Manifold system (1) according to one of the preceding claims, characterized in that the outlet opening (37) of the outermost LSI manifold (30, 33) is closed by a cover (4).

11. Manifold system (1) according to one of the preceding claims, characterized in that the LSI manifold (30, 31) is connected to the housing (2) in a materially bonded manner by welding or soldering or gluing.

12. Manifold system (1) according to one of the preceding claims, characterized in that the housing (2) has only one connection opening (22) via which two LSI manifolds (30-31) are connected directly or indirectly.

13. Manifold system (1) according to one of the preceding claims, characterized in that the housing (2) connects the outlet openings with a housing of a turbocharger and for this purpose forms a supporting component arranged between the engine block and the turbocharger.

14. System consisting of a manifold system (1) according to one of the preceding claims and an internal combustion engine.