Turbines, in particular for exhaust gas turbochargers for motor vehicles, and internal combustion engines

Abstract

The invention relates to a turbine (10) for an exhaust gas turbocharger, which comprises a turbine housing (12) with at least two channels (14, 16) that are fluidically separated from one another in at least a partial region and through which exhaust gas of an internal combustion engine can flow, a turbine wheel (24) accommodated in the turbine housing (12) and drivable by the exhaust gas, at least one bypass passage (32) through which the turbine wheel (24) is bypassed by at least a part of the exhaust gas, at least one through-flow opening (34) fluidly connecting the channels (14, 16) to one another, and at least one valve member (36) whose position can be adjusted between a closed position for closing the bypass passage (32) and the through-flow opening (34) and at least one open position for opening the bypass passage (32) and the through-flow opening (34), respectively, in at least a partial region, the valve member (36) having at least one flow passage (44) passing through the valve member (36) and through which the exhaust gas can flow.

Description

[Technical Field]

[0001] The present invention relates to a turbine, in particular for an exhaust gas turbocharger of a motor vehicle, according to the preamble of claim 1. Furthermore, the invention relates to an internal combustion engine for a motor vehicle. [Background technology]

[0002] Such a turbine, particularly for an exhaust-gas turbocharger of a motor vehicle, is already known, for example from DE 10 200 04 14 522. The turbine has a turbine housing with at least two channels, which are fluidically separated from one another in at least partial regions and through which the exhaust gas of an internal combustion engine can flow. DE 10 200 04 14 522 A1 further discloses a turbine for an exhaust-gas turbocharger. DE 10 200 04 14 522 A1 further discloses ... a turbine for a turbocharger. EP 1 099 593 A1 discloses an internal combustion engine with an exhaust gas turbocharger. EP 1 099 593 A1 discloses an exhaust gas turbocharger for an internal combustion engine. Furthermore, a turbocharger system is known from EP 1 099 593 A1. [Patent Document 1] DE102013002894B4 [Patent Document 2] DE102016208163A1 [Patent Document 3] DE112015005540B4 [Patent Document 4] DE102016208160A1 [Patent Document 5] DE102006058102A1 [Patent Document 6] DE102011115206A1 [Patent Document 7] EP3401528A1 Summary of the Invention [Problem to be solved by the invention]

[0003] The object of the present invention is to provide a turbine for an exhaust gas turbocharger and an internal combustion engine having at least one such turbine, which makes it possible to realize a particularly advantageous channel connection. [Means for solving the problem]

[0004] This problem is solved by a turbine having the features of claim 1 as well as by an internal combustion engine having the features of claim 6. Advantageous embodiments, including preferred developments of the invention, are set forth in the further claims.

[0005] A first aspect of the present invention relates to a turbine for an exhaust gas turbocharger, particularly for a motor vehicle. This means that a motor vehicle, also referred to simply as a vehicle, preferably configured as a motor vehicle, particularly as a passenger car, has an exhaust gas turbocharger with a turbine in its fully manufactured state. In particular, a motor vehicle, in its fully manufactured state, has an internal combustion engine, such as a reciprocating engine, also referred to as an engine or internal combustion engine, by which the motor vehicle can be driven. During the combustion operation of the internal combustion engine, a combustion process takes place in the internal combustion engine. During each combustion process, a respective fuel-air mixture, also referred to simply as a mixture, is combusted, resulting in the engine's exhaust gases. As will be explained in more detail below, the turbine can be driven by the exhaust gases. The mixture here contains at least air and, particularly, a liquid fuel. The fuel is preferably gasoline, i.e., a gasoline fuel. Thus, the internal combustion engine is preferably configured as a gasoline engine. The turbine has a turbine housing with at least two or exactly two channels that are fluidly separated from each other in at least a partial region. Each channel can be traversed by the exhaust gases. The turbine further comprises a turbine wheel, which is rotatably accommodated in the turbine housing. The turbine wheel can be driven by the exhaust gas and thus can rotate, for example, about a rotation axis relative to the turbine housing. In particular, each channel can be configured as a respective helical passage, for example, extending at least substantially helically around the circumference of the turbine wheel in the circumferential direction of the turbine wheel. In particular, the turbine wheel is accommodated in an accommodation space, also referred to as an accommodation area, of the turbine housing. In this case, for example, each channel communicates with the accommodation area, so that the exhaust gas flowing through the respective channel can be guided from the respective channel into the accommodation area and therewith to the turbine wheel. In this way, the exhaust gas flowing through the respective channel flows out of the respective channel into the accommodation area and then impinges on the turbine wheel, thereby driving it.

[0006] The turbine, in particular the turbine housing, has at least one or exactly one bypass passage through which at least a portion of the exhaust gas can bypass the turbine wheel. In particular, the bypass passage extends at least partially inside the turbine housing and / or is at least partially defined directly by the turbine housing. The requirement that at least a portion of the exhaust gas can bypass the turbine wheel via the bypass passage is understood to mean that the exhaust gas flowing through the bypass passage bypasses the turbine wheel, i.e., does not drive the turbine wheel. The bypass passage is also called a wastegate, a wastegate passage, a bypass, or a bypass passage.

[0007] The turbine, in particular the turbine housing, further has at least one or exactly one through-flow opening, via which the channels can be fluidically connected to one another. In particular, the through-flow opening can be defined, in particular directly, by the turbine housing. In particular, the through-flow opening is a through-flow opening that is different from, separate from, or additional to the bypass passage, via which the channels can be fluidically connected to one another. The bypass passage is usually used to adjust, in particular to control, the charge pressure provided by the exhaust-gas turbocharger.

[0008] The turbine further comprises at least one valve member that is adjustable, i.e., movable, particularly relative to the turbine housing, between a closed position and at least one open position. In the closed position, the bypass passage and the through-flow opening are each particularly completely closed, i.e., fluidically blocked, by the valve member, also referred to as a valve body. Thus, in the closed position, preferably, exhaust gas does not flow through the bypass passage, and in the closed position, preferably, exhaust gas does not flow through the through-flow opening, so that, for example, in the closed position, the fluid connection between the channels created by the through-flow opening is prevented, i.e., closed. It is particularly intended that, in the closed position, the channels are fluidically separated, particularly completely. In the open position, the valve member opens both the bypass passage and the through-flow opening, respectively, at least in a partial region, particularly simultaneously, so that, in the open position, exhaust gas can enter the bypass passage and flow through it. Furthermore, in the open position, the exhaust gas can flow through the through-flow openings and thus can flow, i.e., transfer, for example, from one of the channels to the respective other channel via the through-flow opening.

[0009] When the channels are fluidically separated from one another by fluidly closing, i.e., fluidly blocking, the through-flow openings by the valve member in the closed position, so-called dynamic pressure supercharging can be realized for supercharging the internal combustion engine, i.e., for supplying compressed air to the internal combustion engine. When the through-flow openings are opened, i.e., the channels are connected to one another via the through-flow openings, so-called static pressure supercharging can be realized for supercharging the internal combustion engine.

[0010] The valve member is preferably of one-piece construction, i.e., a one-piece body. In other words, the valve member is preferably not an assembly of several components that are constructed separately and connected to one another, but is preferably a unitary, i.e., one-piece, body constructed as a monoblock that is manufactured in one piece. Most preferably, when the valve member is adjusted from the closed position to the open position, it is intended to simultaneously open both the bypass passage and the through-flow opening, each at least in a partial area.

[0011] To achieve a particularly advantageous fluid connection of the turbine channels and thus a particularly advantageous channel connection, the valve member according to the invention is provided with at least one or exactly one flow passage extending completely through the valve member, particularly into the interior of the valve member, through which the exhaust gas can flow, such that this flow passage is completely defined by the valve member (valve body), for example completely around its circumference, particularly over its entire extent in the flow direction of the exhaust gas flowing through the through-passage. The flow passage can be used to fluidly connect the channels in addition to only partially opening the through-passage openings, for example, in the open position. That is, in particular, if the valve member itself, for example, opens a first partial region of the through-passage opening in the open position, but still projects into a second partial region of the through-passage opening, particularly adjacent to the first partial region, i.e., is located in the second partial region, the flow passage can be used to fluidly connect the channels. In this case, for example, the flow passage is located in part of the second partial region, or the exhaust gas can flow through the open first partial region and the flow passage and thereby through part of the second partial region, so that, for example, a large volume flow and / or mass flow of the exhaust gas can pass from one of the channels to the respective other channel.

[0012] For example, the flow passage may be formed by at least one or exactly one bore, thereby enabling a particularly cost-effective implementation of the flow passage. For example, the turbine may be a segment turbine with at least two channels or exactly two channels, thereby enabling a particularly advantageous or efficient operation. The present invention presupposes a channel connection already known from the prior art, which is variable in that the through-flow openings can be completely fluidly blocked and thus closed by moving the valve member to a closed position, while the through-flow openings can be opened at least partially by moving the valve member to an open position. It is particularly conceivable that the valve member can be adjusted, i.e., moved, to the closed position and at least one of the aforementioned open positions, as well as to at least one or more other open positions, with the through-flow openings being opened at least partially in each of the other open positions. In particular, in each open position, a respective volumetric flow and / or mass flow of exhaust gas can flow through the through-flow opening, the volumetric flow and / or mass flow being different from one another in these open positions. This allows for a specially tailored, i.e., variable, channel connection, also referred to as a channel connection. The valve member is then endowed with a dual function. On the one hand, it serves as a channel connection valve for selectively closing or opening the throughflow. On the other hand, it serves as a wastegate valve or bypass valve for selectively opening or closing the bypass passage. The valve member then simultaneously defines, particularly in the respective open positions, a first effective surface of the turbine wheel bypass and a second effective surface of the channel connection. Exhaust gases flow through the first effective surface and can enter the bypass passage via this. They also flow through the second effective surface and can thereby transition from one channel to the other. Turbine wheel bypass is understood to mean that at least a portion of the exhaust gases bypasses the turbine wheel.In other words, for example, especially in the open position, the first and second effective surfaces are each at least partially defined directly by the valve member, in particular by the outer circumferential jacket surface of the valve member, with the exhaust gas flowing through the first effective surface bypassing the turbine wheel and the exhaust gas flowing through the second effective surface transitioning from one channel to the other. This allows for dynamic pressure charging, for example, during load jumps or when high requirements are placed on the transient behavior of the internal combustion engine. On the other hand, the turbine can be operated with relatively good efficiency even at rated power. One characteristic of the valve member can be its area ratio or an area ratio, i.e., the ratio of the first effective surface to the second effective surface, or vice versa. The contour of the valve member, in particular on its outer circumferential side, can then define the aforementioned surfaces and thus the area ratio and the resulting exhaust gas mass flow ratio depending on the respective opening position and thus, in particular, on the opening angle of the valve member. The mass flow ratio is understood to be the ratio of a first mass flow to a second mass flow of exhaust gas, where, for example, the first mass flow flows through the first surface or bypasses the turbine wheel, and the second mass flow flows through the through-flow opening or transitions from one channel to the other.

[0013] However, conventional solutions do not allow for any geometrically desirable channel connection characteristics from an engine standpoint. Compared to conventional solutions, the present invention allows for an improved, particularly tailored, adaptation or adjustment of the mass flow ratio, particularly in the respective opening positions. In particular, the present invention expands the possibilities, particularly in terms of adapting the mass flow ratio in the respective opening positions, so that not only the geometric clearance surface but also the effective flow surface is changed. For this purpose, according to the present invention, a flow passage, also referred to as a through-flow passage, is formed in the valve member. This makes this possible, for example, even when the valve member has a small opening angle, i.e., when the valve member is only slightly opened, in which case the valve member opens both the bypass passage and the through-flow passage, particularly simultaneously, but only slightly opens the through-flow opening. This is possible, for example, in such a way that the first subregion mentioned above is opened, while the valve member itself is, for example, still located in the second subregion, so that exhaust gas can flow through both the opened first subregion and the flow passage. This allows for a strong or wide channel connection to be realized, even with a small opening angle or a small opening of the valve member. In other words, a large volume flow and / or mass flow can be realized that can transfer from one of the channels to the respective other channel, especially with a small opening angle or even with a small opening angle of the valve member. Due to the kinematics of the valve member, a relatively small channel connection mass flow can thus be generated even with a small opening angle, and this mass flow increases significantly at larger opening angles. Each channel connection mass flow is understood to be the respective mass flow of exhaust gas that transfers from one of the channels to the respective other channel.

[0014] The flow channel can be configured such that, for example, a main exhaust gas flow through the first partial region can be used to activate an additional exhaust gas flow through the flow channel. The present invention thus allows a desired or required channel connection characteristic to be realized, while, for example, simultaneously achieving or maintaining an advantageous, particularly advantageously small, valve member size. This allows for a power gain to be realized without generating additional forces in the kinematics intended for the valve body movement or position adjustment. Kinematics intended for the valve member movement, particularly between the open and closed positions, include, for example, an electric adjustment element, also referred to as an E adjustment element. An electric adjustment element is an electrically actuable actuator, with which the valve member can be moved from the closed position to the open position and / or from the open position to the closed position, for example, using electrical energy.

[0015] In particular cases, and preferably, in order to allow the exhaust gases to pass through the flow passage, the flow passage is intended to have at least one length region that extends in an arch shape, in particular in at least one or just one imaginary plane.

[0016] Alternatively or additionally, the flow passage is intended to have at least two length regions which extend obliquely or perpendicularly to one another, in particular in at least one or exactly one imaginary plane, so that the exhaust gas can be guided particularly advantageously through the flow passage and thus through the valve member.

[0017] Alternatively or additionally, the flow channel can extend in at least a partial region, in particular in at least one or exactly one imaginary plane, in an S- or Z-shape, which allows a particularly advantageous arrangement of the respective points at which the exhaust gases enter and exit the flow channel, and thus a particularly advantageous guidance of the exhaust gases.

[0018] It has thus been shown to be particularly advantageous if, in the open position of the valve member, the channels are fluidically connected to one another via the flow passages. In other words, the flow passages are preferably arranged or configured so that, in the open position, the channels are fluidically connected to one another via the flow passages. In other words, in the open position, the exhaust gas flows from one of the channels into the flow passage, then flows through the flow passage and into the other channel via the flow passage, whereby the flow passages are particularly configured to guide the exhaust gas from one of the channels to the respective other channel in the open position. This allows for particularly favorable operation, since the channels can be fluidically connected to one another advantageously strongly even with a small opening angle, i.e., even with a small opening in the valve member.

[0019] It has also proven to be particularly advantageous if, in the closed position, the fluid connection between the channels caused by the flow passage is prevented. In other words, it is preferable that, in the closed position, the through-flow openings are particularly completely closed by the valve member, and it is intended that, in the closed position, the channels are not fluidically connected to one another even via the flow passage. In this way, a strict separation of the channels can be realized in the closed position, so that, depending on the particular needs, it is possible to switch between a fluid connection of the channels and a fluid separation of the channels.

[0020] Another embodiment is characterized in that in the closed position the flow passage is fluidically blocked by a wall region of the turbine housing, which makes it possible to ensure in a particularly simple manner that in the closed position the exhaust gas cannot pass from one of the channels to the other, respectively, so that the channels can be fluidically separated or connected to one another as required and selectively.

[0021] In a particularly advantageous embodiment of the invention, it is provided that in the closed position the through-flow openings are completely closed by the valve member, so that a particularly precise and defined switching can be effected between channel connection, i.e. the fluidic connection of the channels with one another, and channel separation, i.e. the state in which the channels are particularly completely fluidically separated from one another, thereby enabling particularly advantageous operations to be realized.

[0022] A second aspect of the invention relates to an internal combustion engine, also referred to simply as an internal combustion engine or engine, for a motor vehicle, e.g., a reciprocating engine, having at least one exhaust gas turbocharger with a turbine according to the first aspect of the invention. Advantages and advantageous features of the first aspect of the invention can be considered as advantages and advantageous features of the second aspect of the invention, and vice versa.

[0023] Further advantages, features and details of the present invention will become apparent from the following description based on preferred embodiments and drawings. The features and combinations of features mentioned in the above description and in the following description of the figures and / or shown only in the figures can be used not only in the respective combinations presented, but also in other combinations or alone without departing from the scope of the present invention. [Brief explanation of the drawings]

[0024] [Figure 1] 1 shows a schematic perspective view of a turbine for an exhaust gas turbocharger of an internal combustion engine in part; [Figure 2] 2 shows another schematic perspective view of a turbine in part; [Figure 3] 2 shows another schematic perspective view of a turbine in part; [Figure 4] 1 shows a schematic perspective view of a first embodiment of a valve member of a turbine; [Figure 5] FIG. 1 shows a schematic perspective view of a second embodiment of a valve member; DETAILED DESCRIPTION OF THE INVENTION

[0025] In the various figures, identical or functionally identical elements are provided with the same reference numerals.

[0026] 1 and 2 each partially show a turbine 10 for an exhaust gas turbocharger of an internal combustion engine in a schematic perspective view. The internal combustion engine is configured, for example, as a reciprocating engine and has a plurality of combustion chambers. By way of example, the internal combustion engine has at least four or even exactly four combustion chambers. Each combustion chamber is partially delimited by a respective cylinder. A respective piston is accommodated in each cylinder for translational movement, and each combustion chamber is partially defined by the respective cylinder and partially by the piston accommodated in the respective cylinder for translational movement. During combustion operation of the internal combustion engine, a combustion process takes place in the combustion chamber. In each combustion process, a fuel-air mixture, also simply referred to as a mixture, is combusted. Each mixture contains at least air and, in particular, a liquid fuel. The internal combustion engine is preferably a gasoline engine. As a result of each combustion process, exhaust gases of the internal combustion engine are produced. The exhaust gases flow out of the respective combustion chambers and can flow into and through the exhaust system of the internal combustion engine. Here, the turbine 10 of the exhaust gas turbocharger is arranged in the exhaust gas installation, also called the exhaust pipe.

[0027] An exhaust gas turbocharger has a compressor arranged in the intake manifold, also called the suction manifold, of an internal combustion engine, through which the aforementioned air can flow and which guides it towards and into the combustion chamber. The compressor can compress the air flowing through the intake manifold.

[0028] As can be seen from FIGS. 1 and 2 , the turbine 10 has a turbine housing 12 with exactly two channels 14 and 16, which are fluidly separated from one another and through which exhaust gas can flow. In the embodiment shown in FIGS. 1 and 2 , the turbine 10 is configured as a two-channel segment turbine. This means that each channel 14, 16 has a respective outlet opening 18, 20 and communicates with a receiving area 22 of the turbine housing 12 via the respective outlet openings 18, 20. The outlet openings 18 and 20 are arranged consecutively in the circumferential direction of the turbine 10, i.e., one behind the other. The turbine 10 further has a turbine wheel 24 accommodated in the receiving area 22 and thus in the turbine housing 12, where it can rotate relative to the turbine housing 12 about its axis of rotation. The circumferential direction of the turbine 10 described above extends around the axis of rotation, so that the outlet openings 18 and 20 are arranged consecutively in the circumferential direction of the turbine wheel 24. Here, each channel 14, 16 is configured as a spiral passage. Channels 14 and 16 are fluidly separated from one another by a separating wall 26 in turbine housing 12. In Figure 1, arrow 28 designates a first flow of exhaust gas, in this example through channel 14. Arrow 30 designates a second flow of exhaust gas through turbine housing 12, which will be described in more detail below.

[0029] The turbine 10, in particular the turbine housing 12, has a bypass passage, indicated by arrow 32, through which at least a portion of the exhaust gas can bypass the turbine wheel 24. As indicated by arrow 32, the exhaust gas flowing through the bypass passage bypasses the turbine wheel 24 and therefore does not drive it. The exhaust gas flowing through the respective channels 14, 16 and guided by the respective channels 14, 16 into the receiving area 22 strikes the turbine wheel 24 and thereby drives it to rotate about its axis of rotation relative to the turbine housing 12. The compressor then has a compressor wheel arranged in the intake manifold, which can be driven by the turbine wheel 24, in particular via a shaft. By driving the compressor wheel, the compressor wheel can compress the air flowing through the intake manifold.

[0030] The turbine 10, and in particular the turbine housing 12, in this example has exactly one through-flow opening 34 formed in the separation wall 26. As will also be explained in more detail below, the channels 14 and 16 can be fluidly connected to one another by the through-flow opening 34, in particular at exactly one point.

[0031] The turbine 10 has a valve member 36, also referred to as a valve body, which can be partially seen in FIG. 1 . The valve member 36 is positionable relative to the turbine housing 12 between a closed position, in which the bypass passage and the through-flow opening 34 are completely closed, and at least one open position, clearly shown in FIGS. 1 and 2 , in which the bypass passage and the through-flow opening 34 are at least partially open, respectively. With reference to arrows 28 and 32 and also to arrow 38, it becomes clear that the exhaust gas flows, for example, first through the channel 14. When the valve member 36 is in the open position, for example, a first portion of the exhaust gas flowing through the channel 14 first leaves the channel 14, passes through the through-flow opening 34, and enters the channel 16 via the through-flow opening 34. The first portion then flows through the channel 16 and is guided by the channel 16 into the accommodation area 22 and thus to the turbine wheel 24. A second portion of the exhaust gas initially flowing through the channel 14 remains in the channel 14 and is guided by the channel 14 toward the receiving area 22, into which it enters, and thereby toward the turbine wheel 24. The first portion of the exhaust gas is indicated by arrow 38, and the second portion by arrow 28. For example, a third portion of the exhaust gas initially flowing through the channel 14 flows from the channel 14, particularly via the through-flow opening 34, into the bypass passage, and then flows through the bypass passage and thereby bypasses the turbine wheel 24, as indicated by arrow 32, due to the valve member 36 being in the open position. In the closed position, the valve member 36 particularly completely closes the through-flow opening 34 and thus completely blocks off the flow. Preferably, the valve member 36 completely closes, i.e., completely blocks off the flow of the bypass passage in the closed position. In the open position, the valve member 36 opens both the through-flow opening 34 and the bypass passage, at least in a partial area.

[0032] 1, the turbine 10 has an actuator 40, also referred to as an adjusting member, which is shown separately and is capable of moving the valve member 36, for example in a closed position, to an open position and / or from an open position to a closed position relative to the turbine housing 12. For example, the actuator 40 is an electric actuator, i.e. an electrically operable actuator, and therefore the actuator 40 is also referred to as an E adjusting member. Highly preferably, the valve member 36 is intended to simultaneously, at least partially, open both the bypass passage and the through-flow opening 34 when adjusted from the closed position to the open position.

[0033] In order to realize a particularly advantageous fluid connection of the channels 14 and 16, also referred to as a channel connection, the valve member 36, as can be seen most clearly in a combined view of Figures 4 and 5, has at least one, or as intended in Figures 4 and 5, exactly one flow passage 44 extending in particular completely through the valve member 36 and thus into the interior of the valve member 36, through which exhaust gas can flow as indicated by arrow 42 in Figure 4, and which is in particular completely defined by the valve member 36 in particular over its entire extension into the valve member 36 and completely around the circumference of the flow passage 44. The arrow 42 in Figure 4 indicates the flow of exhaust gas through the flow passage 44. The turbine 10 is then configured in such a way that the channels 14 and 16 are fluidly connected to one another via the flow passage 44 when the valve member 36 is in the open position.

[0034] For example, the valve member 36 can be pivoted between an open position and a closed position, particularly about a pivot axis. Thus, the valve member 36 can be pivoted, for example, into different angular positions or attitudes, also referred to as pivot positions. One, particularly exactly one, of these angular positions is the closed position. The remaining or all other pivot positions, also referred to as opening angles, are open positions in which the valve member 36 opens both the bypass passage and the through-flow opening 34, particularly simultaneously. In particular, at small opening angles, for example, the valve member 36 opens a first partial area of ​​the through-flow opening 34, but the valve member 36 still projects into a second partial area of ​​the through-flow opening 34 that is particularly adjacent to the first partial area, so that the valve member 36 is still located in the second partial area at small opening angles. If the valve member 36 did not have a flow passage such as the flow passage 44 through which the exhaust gas could flow, the exhaust gas would only be able to flow through the open first partial region of the through-flow passage 34, and the second partial region would not be available for passing from one of the channels 14 and 16 to the respective other channel 16 or 14. However, the valve member 36 does have a flow passage 44, which extends, for example, from its first end E1 to its second end E2. Here, by way of example, end E1 is arranged in the second partial region of the through-flow opening 34, particularly in the case of a small opening angle, so that the exhaust gas can enter one of the ends E1 and E2 into the flow passage 44, flow from one of the ends E1, E2 to the other end E2, E1, and thus flow through the flow passage 44, and then be guided by the flow passage 44 from one of the channels 14 and 16 to the respective other channel 16 or 14. In this way, the exhaust gas can not only flow from one of the channels 14 and 16 to the other channel 16 or 14, respectively, through the open first partial region, but the exhaust gas can also flow through the flow passage 44, and in this way flow from one of the channels 14 and 16 to the other channel 16 or 14, respectively, through the flow passage 44.In this way, the flow passage 44 is a fluid connection between the channels 14 and 16 that is provided in addition to the first partial area that is opened, so to speak, so that, for example, a large exhaust gas mass flow can transfer between the channels 14 and 16, especially while the valve member 36 only opens the bypass passage very slightly.

[0035] 4 shows a first embodiment of the valve member 36. In the first embodiment, the end E2 is located at the axial end face 46 of the valve member 36.

[0036] Typically, and especially when the valve member 36 does not have a flow passage, such as the flow passage 44, through which exhaust gas can flow, the single, in particular outer circumferential contour of the valve member 36, also referred to as the valve body, defines the ratio, also referred to as the mass flow ratio, between the first mass flow of exhaust gas flowing through the bypass passage in the open position and the second mass flow of exhaust gas flowing through the through-flow opening 34 in the open position. The mass flow ratio then depends on the respective opening angle of the valve member 36. However, conventional approaches do not allow for any desired channel connection characteristics to be generated geometrically, i.e., via the contour of the valve member 36, which are desirable from the engine's point of view. Depending on the size of the exhaust gas turbocharger, the specifications of the actuator 40, and the inflow rate into the catalytic converter, many parameters of the turbine 10 and, in particular, the valve member 36 are specified, in particular taking into account the opening and closing of the bypass passage and the channel connection. In particular, the opening kinematics for positioning the valve member 36, the shape of the outer circumferential side, and therefore any subsequent changes to the contour of the outer circumferential side of the valve member 36, directly affect the required protection range. Valve member 36 is therefore given special significance in defining the channel connections and in particular their properties.

[0037] In an engine process simulation, engine targets can be linked to a target curve for the channel connection characteristic. Such a target curve, also referred to simply as a curve, often indicates a wide adjustment range for the valve member 36, within which the connection surface of the through-flow opening 34, also referred to as the channel connection surface, increases. The second surface, also referred to as the wastegate surface, through which exhaust gases can flow into the bypass passage, only increases significantly as the opening angle of the valve member 36 increases. For example, if the means for adjusting the valve member 36 are exhausted and an overall increase in the size of the valve member 36 becomes unfeasible, a further increase in the channel connection surface is no longer feasible at the current level. Therefore, it is possible to aim for an even closer approximation of the channel connection characteristic to the target curve in other ways, for example, by means of additional structural elements. In this case, additional structural elements should not have any effect on the channel connection characteristic when the valve member 36 is closed, i.e., in the closed position. Simulations have shown that, despite the complex and time-consuming shape, i.e., contour, particularly on the outer circumferential side, of the valve member 36, a fairly strong or extensive channel connection can be realized even without the flow passages 44, but in some cases the entire partial area of ​​the through-flow openings 34 that are released by the valve member 36 in the respective open position may not be available for the fluid connection of the channels 14 and 16. This may be due to a less than optimal flow guidance towards the valve member 36, particularly in the case of small design sizes of exhaust-gas turbochargers.

[0038] An at least approximately accurate optimization of the channel connection can be achieved by providing at least one or just one flow passage 44 in the valve member 36. By providing the flow passage 44 in the valve member 36, a new cross section for the channel connection is made available for the exhaust gas or its flow, since the exhaust gas can pass from one of the channels 14 and 16 to the respective other channel 16 or 14 not only via the open first partial region of the through-flow opening 34 but also via the flow passage 44, which is open in the open position.

[0039] In the first embodiment shown in FIG. 4 , for example, end E2 is the outlet of the passage, which in the first embodiment is discharged at the level of the separating web. This eliminates the fluid connection between the channels 14 and 16 when the valve member 36 is in the closed position, in particular because end E2 and thus the flow passage 44 are closed, i.e., fluidically blocked, in the closed position, in particular because, for example, the axial end face 46 and thus end E2 directly abuts against the corresponding wall area of ​​the turbine housing 12 in the closed position. In this way, for example, the entire outlet (end E2) is closed by the wall area. It has also been found that the locally high velocities or the resulting low static pressures at the separating web can be used to guide as large a mass flow as possible from the active channels 14, 16 to the passive channels 16, 14. Active channel and passive channel are understood in particular as follows: That is, at least one first combustion chamber, particularly at least two or exactly two first combustion chambers, is assigned to channel 14 and is particularly fluidly connected to channel 14, and at least one second combustion chamber, particularly at least two or exactly two second combustion chambers, is assigned to channel 16 and is particularly fluidly connected to channel 16. The exhaust gas from the first combustion chamber, particularly with respect to channels 14 and 16, first flows only into channel 14, but not into channel 16. The exhaust gas from the second combustion chamber, particularly with respect to channels 14 and 16, first flows only into channel 16, but not into channel 14. In FIG. 1 , channel 14 is the active channel, and channel 16 is the passive channel, because, for example, only the exhaust gas from the first combustion chamber is provided with respect to the first and second combustion chambers. Thus, the exhaust gas from the first combustion chamber first flows into channel 14 and, when the valve member 36 is in the open position, at least partially flows from channel 14 into channel 16. In FIG. 2, channel 16 is the active channel, whereas channel 14 is the passive channel.Because in FIG. 2 , with respect to the first and second combustion chambers, only the second combustion chamber provides exhaust gas, but not the first combustion chamber, exhaust gas from the second combustion chamber first flows into channel 16 and then, when valve member 36 is in the open position, at least partially exits channel 16 at point S and flows into channel 14. In FIG. 2 as in FIG. 1 , arrows 28 indicate exhaust gases that first flow into the active channel, remain there, and are guided by the active channel toward and into the receiving area 22 and thus toward the turbine wheel 24. In FIG. 2 as in FIG. 1 , arrows 38 indicate exhaust gases that first flow into the active channel, but do not remain there, but instead flow through the at least partially opened through-flow opening 34 at point S, thus transitioning from the active channel to the passive channel. Furthermore, in FIG. 2 as in FIG. 1 , arrows 32 indicate exhaust gases that flow through the bypass passage.

[0040] In particular, since the exhaust gas from the active channel can use not only the first partial region, which is released in the open position, but also the flow passage 44 to transition from the active channel to the passive channel, a large mass flow of exhaust gas can be realized even with a small opening angle. Compared to a valve member 36 without the flow passage 44, a clear increase in the channel connection, i.e., the mass flow of exhaust gas transitioning from the active channel to the passive channel, can be observed. In particular, the provision of the flow passage 44 allows for an increase in turbine power while keeping the position of the valve member 36 the same.

[0041] For example, the valve member 36 itself is solid and, in this example, includes a flow passage 44. For example, the flow passage 44 is formed by at least one bore, or by exactly one bore, or by at least or exactly two bores. The flow passage 44 is an internal flow passage of the valve member 36, which allows for particularly advantageous channel connections to be realized. In the closed position, the flow passage 44 does not create a fluid connection between the channels 14 and 16. However, in the open position, the flow passage 44 creates a fluid connection between the channels 14 and 16 in addition to the first open partial region, thereby creating an additional mass flow, also referred to as a channel-connecting mass flow, of exhaust gas passing from the active channel to the passive channel. This additional channel-connecting mass flow is in addition to the mass flow of exhaust gas flowing through the first open partial region. The additional flow passage 44 can be formed by a single bore or by multiple bores that are fluidly interconnected by crossing each other. Of course, it is contemplated that the valve member 36 may have multiple flow passages, such as the flow passage 44, that are fluidly separated from one another within the valve member 36. The flow passage 44 may be configured to favor flow, particularly with respect to its radius or diameter and / or with respect to its chamfer or chamfers.

[0042] An inlet of the flow passage 44, for example provided at or formed by end E1, through which exhaust gas can enter the flow passage 44 from the respective active channel, is directly in the transitioning exhaust gas or its flow when exhaust gas is flowing in the respective active channel and thus through the channel, and when, for example, the valve member 36 is significantly open and the opening angle is, for example, greater than 30 percent of the maximum opening angle, thereby allowing the exhaust gas to enter the flow passage 44 directly. An outlet of the flow passage 44, for example provided at and formed by end E2, is, for example, at such a point on the valve member 36 that it is blocked when the valve member 36 is closed, i.e., in the closed position.

[0043] In the first embodiment shown in FIG. 4, the flow passage 44 ends directly at an end E2 in the separating wall of the channel junction.

[0044] 5 shows a second embodiment in which the end E2 is arranged behind the valve member 36, which in the closed position abuts directly against a wall, also called wall area, formed for example by a housing in which the valve member 36 is arranged, such as the turbine housing 12, or a separate housing which is constructed separately from the turbine housing 12 and which is connected to the turbine housing 12. [Explanation of symbols]

[0045] 10 Turbine 12 Turbine housing 14 channels 16 channels 18 Outlet opening 20 Outlet opening 22 Containment Area 24 Turbine Wheel 26 Separation wall 28 Arrow 30 Arrow 32 Arrow 34 Through-flow opening 36 Valve Elements 38 Arrow 40 Actuator 42 Arrow 44 Flow passage 46 End face E1 First end E2 Second end

Claims

1. A turbine (10) for an exhaust gas turbocharger, comprising a turbine housing (12) having at least two channels (14, 16), the channels (14, 16) being fluidically separated from one another in at least partial regions and through which exhaust gases of an internal combustion engine can flow, the channels being fluidically separated from one another by a separating wall (26) of the turbine housing (12), a turbine wheel (24) accommodated in the turbine housing (12) and being drivable by the exhaust gases, and at least one bypass passage (32) through which the turbine wheel (24) can be bypassed by at least a portion of the exhaust gases, the turbine (10) having at least one through-flow opening (34) formed in the separation wall (26) for fluidly connecting the bypass passage (32) and the through-flow opening (34) with each other, and at least one valve member (36) whose position can be adjusted between a closed position for closing the bypass passage (32) and the through-flow opening (34) and at least one open position for opening the bypass passage (32) and the through-flow opening (34) at least in a partial area, the valve member (36) having at least one flow passage (44) penetrating the valve member (36) and through which the exhaust gas can flow, - in said closed position, said through-flow opening (34) is completely closed by said valve member (36); in the closed position, the fluid connection between the channels (14, 16) created by the flow passage (44) is prevented, so that in the closed position, the channels (14, 16) are not fluidly connected to each other even via the flow passage (44); in the open position, the valve member (36) opens a first partial area of ​​the through-flow opening (34) but still projects into a second partial area of ​​the through-flow opening (34) adjacent to the first partial area, and is thereby arranged in the second partial area, and the flow passage (44) is located in part of the second partial area, whereby the flow passage (44) forms a fluid connection between the channels (14, 16) provided in addition to the opened first partial area, and the exhaust gas can flow through the opened first partial area and the flow passage (44) and part of the second partial area, - said flow passage (44) has at least one arcuately extending length region; and / or - said flow passage (44) has at least two length regions extending obliquely or perpendicularly to each other; and / or The turbine (10), characterized in that the flow passage (44) extends in an S-shaped or Z-shaped manner at least in a partial region.

2. The turbine (10) of claim 1, wherein the channels (14, 16) are fluidly connected to one another via the flow passage (44) when the valve member (36) is in the open position.

3. 3. The turbine (10) of claim 1 or 2, wherein the flow passage (44) is fluidly blocked by a wall area of ​​the turbine housing (12) in the closed position.

4. 3. The turbine (10) according to claim 1 or 2, characterized in that in the closed position, the through-flow opening (34) is completely closed by the valve member (36).

5. An internal combustion engine for a motor vehicle, comprising at least one exhaust gas turbocharger comprising a turbine (10) according to claim 1 or 2.

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