DE102011085161B4 - Coolable flow-guiding housing of an exhaust gas component - Google Patents

Abstract

Housing with at least one flow channel for directing a fluid flow through the housing (20, 30, 40), wherein the housing (20, 30, 40) - at least one for limiting the section of the at least one flow channel (21) formed line section (25), and - At least one for limiting the section of the at least one flow channel (21) formed cooling section (22, 24), wherein the cooling section (22, 24) at least one coolant channel (23) for cooling of the flow channel (21) flowing fluid stream comprises, characterized in that a wall of the at least one line section (25) delimiting the flow channel (21) is formed, at least in a first region (A), by a closure element (26) designed as a separate, single-walled component.

Description

The invention relates to a housing having at least one flow channel for conducting a fluid flow through the housing, in particular a housing for an exhaust gas component of a Abgasstranges a motor vehicle with at least one flow channel for conducting an exhaust gas flow through the housing.

In the development of internal combustion engines, a reduction of fuel consumption is of particular importance, so that enormous efforts are made to implement them. An effective measure proves to avoid a Gemischanfettung for component protection as possible.

However, this measure results in an increased exhaust gas temperature, which can be detrimental to the exhaust gas components following in an exhaust line, such as exhaust manifold, exhaust gas turbocharger or catalyst. In particular, an excessively high exhaust gas temperature can render the components mentioned unusable or at least impair their function.

As a countermeasure therefore increasingly exhaust manifold and / or turbine housing of the exhaust gas turbocharger are equipped with a fluid cooling. This makes it possible to withdraw enthalpy from the exhaust gas before it enters the respective temperature-sensitive exhaust gas components in order to reduce the exhaust gas temperature in the downstream exhaust gas system to defined limit temperature values.

The fluid cooling is usually realized by means of a cooling jacket, which encloses an exhaust-carrying flow channel of the corresponding exhaust gas component and is flowed through by a cooling medium. As a cooling medium, for example, cooling water is used.

A disadvantage of this arrangement, however, is that the correspondingly executed exhaust gas component compared to a conventional, uncooled exhaust system has a significantly increased space requirements, since the exhaust-gas flow geometry not only has the exhaust-carrying first Bewandung the flow channel, but these in turn completely or partially from the the cooling medium leading cooling jacket is surrounded. This is usually double-walled and thus in turn completed with a second Bewandung the environment. Consequently, the result is a total of a double-walled arrangement with a correspondingly larger space requirement.

However, this additional space required for the cooling jacket and its second Verandung is often not available in today increasingly narrowing engine compartments, so that implementation of the component cooling described in its entirety or partially due to the space requirement is not feasible.

As a further aspect is to be mentioned that for a defined cooling of the flow medium in certain cases, only portions of the component may be cooled in order not to escape the exhaust too much enthalpy, which would have, inter alia, a greatly delayed light-off behavior of the catalyst.

The US 2010/0240268 A1 shows a liquid-cooled cooling jacket for placement on an exhaust manifold. In addition, a liquid-cooled exhaust manifold is described, which is integrally formed and merges the exhaust gas of three separate combustion cylinder. The cooling liquid is introduced via an inlet into a cooling channel of the exhaust manifold and discharged via an outlet after passing through the cooling channel.

The object of the invention is therefore to overcome the disadvantages mentioned above or at least partially reduce.

This object is achieved by means of a housing having the features of independent claim 1 and by means of an exhaust gas component having the features of independent claim 10. Advantageous embodiments result from the respective dependent claims.

• – mindestens einen zum abschnittsweisen Begrenzen des mindestens einen Strömungskanals ausgebildeten Leitungsabschnitt, und
• – mindestens einen zum abschnittsweisen Begrenzen des mindestens einen Strömungskanals ausgebildeten Kühlabschnitt umfasst,

wobei der Kühlabschnitt mindestens einen Kühlmittelkanal zum Kühlen des durch den Strömungskanal strömenden Fluidstroms umfasst, und eine den Strömungskanal begrenzende Wandung des mindestens einen Leitungsabschnitts zumindest in einem ersten Bereich von einem als separates, einwandiges Bauteil ausgeführten Verschlusselement gebildet ist.Accordingly, a housing is provided with at least one flow channel for conducting a flow of fluid through the housing, wherein the housing

• - At least one sectionally limiting the at least one flow channel formed line section, and
• Comprising at least one cooling section formed for limiting in part the at least one flow channel,

wherein the cooling section comprises at least one coolant channel for cooling the fluid flow flowing through the flow channel, and a wall of the at least one line section delimiting the flow channel is formed at least in a first region by a closure element designed as a separate, single-walled component.

It is therefore proposed a housing in general form, which is designed for conducting a fluid flow and at least two sections, a line section and a cooling section comprises. The cooling section is provided for cooling the fluid flow and has for this purpose the one or more coolant channels. These are preferably provided by a multi-walled construction of the cooling section, wherein the multi-walled structure can be embodied, for example, in the form of a single- or multi-channel cooling jacket or at least a partial arrangement of a number of the coolant channels on an outer surface of the cooling section. For example, a first wall of the cooling section defines both a boundary of the flow channel and a first wall for an adjacent coolant channel, which is provided between the first wall and a second wall spaced therefrom. In other words, the cooling section can be designed as a cooling jacket with at least one coolant channel.

The line section is formed completely or only in a first region of the line section of the separate, single-walled closure element. This thus serves primarily to limit the flow channel. Due to the single-walled design, a locally required installation space is smaller than is possible with a cooling arrangement, in particular a multi-walled cooling arrangement. The closure element is designed, for example, such that a course of the flow channel is not impaired in that the closure element continuously continues a course and / or cross-sectional profile of the flow channel in the region of the closure element that is predetermined by the cooling section and / or a second region of the line section. Alternatively, however, the closure element can also be designed such that the flow cross-section of the flow channel is at least locally narrowed or widened.

The closure element described thus makes it possible to locally reduce a housing shape in order to eliminate local space difficulties. In addition, a cooling of the flow channel can be replaced by the closure element in some areas of the housing in a simple manner, thus preventing a cooling of the flowing fluid stream to an undesirable extent.

According to further preferred embodiments, the cooling section and / or a second region of the conduit section are integrally formed. This means that the cooling section is a one-piece component. Likewise, the cooling section, together with the second area of the line section, can be embodied as a common component in one piece or in one piece. An exemplary embodiment is shown below in the figures.

Preferably, the closure element comprises high temperature resistant material, in particular ferritic and / or austenitic stainless steel. The closure element can thus withstand a high temperature loading by the fluid flow despite a single-walled design, without the risk of damage, in particular a "melting through" of the housing or the closure element, due to the "missing" coolant cooling. Depending on the amount of acting forces and temperatures allows the described choice of material according to a wall thickness of the closure element in addition to minimize and thus to keep a required space requirement low. Of course, however, other materials such as metals, fiber composites and / or ceramic materials can be used.

Depending on the choice of the material of the closure element, this can give off enthalpy of the fluid flow due to a convection and radiation acting on the outside of the closure element facing away from the flow channel. However, since this cooling is lower than a coolant cooling, the resulting cooling effect of the entire housing can be varied and defined by means of a variation of the ratio of cooling section and line section or closure element.

Also preferably, the cooling section and / or the second region of the line section may comprise a low-melting material, in particular light metal. Light metal, such as aluminum, has proved to be suitable thanks to the simultaneous coolant cooling, so that melting of the material can be prevented even in the case of a high thermal load by a hot fluid flow. This allows the cooling section or the conduit section to be produced in a simple manner, for example by means of a casting method, and to provide a desired shaping, for example the multi-walled configuration of the cooling section, in a simple and cost-effective manner.

A connection between the closure element and the cooling section and / or the second region of the line section may include, for example, a cohesive, positive and / or non-positive connection. The closure element is preferably fastened to the cooling section and / or to the second region of the line section, for example by means of screws or by gluing or welding, or the components mentioned are connected to one another. It goes without saying that other connecting means or connecting measures encompassed by the mentioned types of connection are also applicable.

Furthermore, the connection may comprise at least one seal. This means that at least one seal for sealing the connection point can be arranged at one or possibly more connection points between the closure element and the cooling section and / or the second region of the line section. For example, for this purpose, among other sealing lips and / or sealing rings can be used.

In accordance with a further embodiment, the closure element also at least partially delimits at least one coolant channel of the cooling section. This assumes that the cooling section has an at least partially opened coolant channel and the closure element is or is connected to the cooling section in such a way that the closure element provides a lining for the coolant channel. For example, the closure element in this way form an end-side closure for a coolant channel in a substantially cylindrical cooling section.

In addition, according to another embodiment, the closure element may be designed as an adapter piece and comprise at least one coupling element for connecting the housing to further components of a flow channel system. In this case, the closure element is provided not only for limiting the flow channel but as an adapter or coupling piece in order to connect the entire housing with the further component of the flow channel system. In this way, the flow channel of the housing can be continued by connecting the further adjacent component in this. Such an adapter piece is particularly preferably provided at an inlet or outlet of the flow channel on the housing. In other words, in this case, the adapter piece forms a connection element assigned to the housing.

It is understood that more than one closure element can be provided on the housing, wherein each closure element can be configured individually according to at least one of the described embodiments.

The housing described can be provided for a variety of different applications.

Preferably, the housing may be a coolable housing of an exhaust gas component of an exhaust line, in particular a coolable housing of an exhaust manifold and / or a turbine of an exhaust gas turbocharger. Particularly preferably, the abovementioned exhaust gas components are provided for an exhaust gas system of a motor vehicle.

Furthermore, an exhaust gas component with a coolable housing for guiding an exhaust gas flow is proposed, wherein the housing is designed according to the given description.

In other words, the invention provides that the initially completely or at least partially coolable flow-guiding housing specifically excluded in one or more sections of a cooling. This happens because in this section or in these sections of the at least one flow channel is not limited by a cooling section but by the separate single-walled closure element and thus no fluid cooling takes place at this point. In particular, this can be provided at locations where the described cooling section would take up too much space or should be avoided for other reasons. Described in an illustrative manner, the flow channel is thus exposed to the outside by opening the housing compared to a conventional component at the corresponding point. At a boundary of the respectively locally openable area, the walls bounding the flow channel and coolant channel merge into one another. In order to shape the exposed through the open housing flow channel or its flow geometry again and complete against the environment, the correspondingly designed closure element is used for this purpose, which preferably consists of the high temperature resistant material and therefore does not require its own cooling. This closure element is attached to the open housing in the manner described and optionally sealed.

In accordance with the procedure described above, a method for converting a standard housing into a housing according to the invention can therefore also be provided, with at least one of the steps described.

In summary, at least the following aspects can thus be realized: On the housing, design space advantages can be specifically achieved at one or more points with one or more closure elements, and a cooling can be defined by changing the heat transfer.

The invention will be described below with reference to the accompanying drawings with reference to several embodiments. In these show:

1 a section through a housing of the prior art,

2 a section through an inventive housing according to a first embodiment,

3 a section through an inventive housing according to a second embodiment,

4 a section through an inventive housing according to a third embodiment.

In 1 a section through a housing of the prior art is shown. The housing 10 is for conducting a fluid flow through a flow channel 11 educated. This includes the housing 10 a cooling section 12 with a first wall 12a which the flow channel 11 limited and thus defines the associated flow geometry. Furthermore, the cooling section comprises 12 a second wall 12b spaced from the first wall 12a is arranged and thus between the first wall 12a and the second wall 12b a gap 12c provides that defines a coolant passage for flowing with a coolant. It can thus take place a heat exchange between the fluid flow of the flow channel and the coolant in the coolant channel.

In contrast, shows 2 a section through an inventive housing 20 according to a first embodiment. This also includes a flow channel 21 for passing a fluid flow through the housing 20 , The housing 20 also includes a conduit section 25 , which is designed for limiting in part the flow channel and this between two cooling sections 22 . 24 Are defined. The first cooling section 22 and the second cooling section 24 are each double-walled and each have a first wall 22a . 24a for limiting the flow channel 21 on. A second wall 22b . 24b is each spaced from the first wall 22a . 24a arranged and defined between a coolant channel 23 , The coolant channel 23 is opposite the pipe section 25 by means of a connection 22d . 24d the first wall 22a . 24a with the second wall 22b . 24b completed. Furthermore, the line section 25 a boundary of the flow channel 21 in relation to an environment ready, and for this purpose comprises on the one hand in a first area A a closure element 26 and on the other hand defines a wall in a second area B. 25a , The closure element 26 is formed single walled and shaped such that a cross section of the flow channel 21 is maintained along its course. Of course, however, other shapes are possible, as far as desired. For example, the closure element could 26 also be designed to narrow the cross-section, in particular as a substantially flat plate (not shown).

The closure element 26 is with the first one 22 and second cooling section 24 by means of a screw connection 27 connected, but other types of connections are possible.

According to the illustrated embodiment, the two cooling sections 22 . 24 with the second region B of the line section 25 , so with the exception of the closure element 26 , integrally connected together and thus form a common body. For example, this can be produced in a casting process. The closure element 26 can be made of a temperature resistant material and thus a high temperature entry due to a hot fluid flow in the flow channel 21 withstand without own active fluid cooling.

Thanks to the proposed housing 20 it is possible to provide cooling by means of at least one cooling section and yet at particularly space critical points a shape of the housing 20 by inserting the closure element 26 to save space.

3 shows a section through an inventive housing 30 according to a second embodiment. The housing 30 differs only by an alternative embodiment of a degree 32d . 34d of the coolant channel 33 from the in 2 described embodiment, so that reference is made essentially to the description given here. The coolant channel 33 in 3 is opposite the pipe section 35 open. A conclusion is made by that in area A of the line section 35 arranged and with the respective cooling section 32 . 34 connected closure element 36 provided. Optionally, at the corresponding connection points between the closure element 36 and the cooling sections 32 . 34 Seals (not shown) for sealing the flow channel 31 and / or the coolant channel 33 be provided.

4 shows a section through an inventive housing 40 according to a third embodiment. This corresponds in many areas to the in 2 illustrated embodiment, so that reference can be made essentially to the description given here. Unlike the in 2 illustrated embodiment, the closure element 46 designed as an adapter piece and comprises a coupling element 46a for connecting the housing to another fluid-carrying component (not shown). In the illustrated embodiment, the coupling element 46a designed as a flange for positive, material and / or non-positive connection with the other component. An embodiment of the closure element 46 as an adapter, the possibility offers in particular the coupling element 46a with very accurate or small tolerances and at the same time the cooling section or the rest of the housing 40 Produce cost-effective with larger tolerances.

In addition, this embodiment allows that occurring during the connection of other components local forces and stresses of the material of the closure element 46 be absorbed and not of the material of the remaining housing, since the latter is usually softer than the material of the closure element 46 , In this way additional strength risks can be minimized.

This means that the closure element need not have a self-contained flow geometry, but one or more openings with a connection geometry in the form of the described coupling element 46a may include for further to be connected and flow adjacent components.

It is understood that more than one closure element can be provided on the housing, wherein each closure element can be configured individually according to at least one of the described embodiments. Thus, for example, according to an embodiment, not shown, a housing having at least one closure element according to the in 3 illustrated embodiment and with at least one closure element according to the in 4 be provided illustrated embodiment. Likewise, for example, these may each be formed as a separate component or integrally as a common component.

Claims (10)

Housing with at least one flow channel for conducting a fluid flow through the housing ( 20 . 30 . 40 ), the housing ( 20 . 30 . 40 ) - at least one sectionally limiting the at least one flow channel ( 21 ) trained line section ( 25 ), and - at least one for limiting in part the at least one flow channel ( 21 ) formed cooling section ( 22 . 24 ), wherein the cooling section ( 22 . 24 ) at least one coolant channel ( 23 ) for cooling the through the flow channel ( 21 ) comprises flowing fluid stream, characterized in that a flow channel ( 21 ) bounding wall of the at least one line section ( 25 ) at least in a first region (A) of a closure element designed as a separate, single-walled component ( 26 ) is formed. Housing according to claim 1, wherein the cooling section ( 22 . 24 ) and / or a second area (B) of the line section ( 25 ) are integrally formed. Housing according to claim 1 or 2, wherein the closure element ( 26 ) comprises high temperature resistant material, in particular ferritic and / or austenitic stainless steel. Housing according to one of claims 1 to 3, wherein the cooling section ( 22 . 24 ) and / or a second area (B) of the line section ( 25 ) comprise a low-melting material, in particular light metal. Housing according to one of claims 1 to 4, wherein a connection between the closure element ( 26 ) and the cooling section ( 22 . 24 ) and / or a second region (B) of the line section ( 25 ) a cohesive, positive and / or non-positive connection ( 27 ). The housing of claim 5, wherein the connection comprises at least one seal. Housing according to one of claims 1 to 6, wherein the closure element ( 26 ) at least one coolant channel ( 23 ) of the cooling section ( 22 . 24 ) at least partially limited. Housing according to one of claims 1 to 7, wherein the closure element ( 26 ) as adapter piece ( 46 ) is formed and at least one coupling element ( 46a ) for connecting the housing ( 20 . 30 . 40 ) with other components of a flow channel system. Housing according to one of claims 1 to 8, wherein the housing ( 20 . 30 . 40 ) is a coolable housing of an exhaust gas component of an exhaust line, in particular a coolable housing of an exhaust manifold and / or a turbine of an exhaust gas turbocharger. Exhaust gas component with a coolable housing for conducting an exhaust gas flow, wherein the housing ( 20 . 30 . 40 ) is designed according to one of claims 1 to 9.

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