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, in particular for an exhaust gas turbocharger of a motor vehicle, is already known, for example from DE 10 200 45 13 A1. This turbine has a turbine housing with at least two channels which are fluidically separated from one another at least in partial regions and through which the exhaust gases of an internal combustion engine can flow. DE 10 200 45 13 A1 further discloses a turbine for an exhaust gas turbocharger. Furthermore, an exhaust gas turbocharger is known from DE 10 200 45 13 A1. Furthermore, DE 10 200 45 13 A1 discloses a turbine for a turbocharger. [Patent Document 1] DE102013002894B4 [Patent Document 2] DE102016208163A1 [Patent Document 3] DE112015005540B4 [Patent Document 4] DE102016208160A1 Summary of the Invention [Problem to be solved by the invention]

[0003] The object of the 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 expedient developments of the invention, are set out in the further claims.

[0005] A first aspect of the invention relates to a turbine, in particular for an exhaust gas turbocharger of a motor vehicle. This means that a motor vehicle, also simply called a vehicle, which is preferably configured as a motor vehicle, in particular as a passenger car, has an exhaust gas turbocharger with a turbine in the fully manufactured state. In particular, a motor vehicle has an internal combustion engine, which is for example configured as a reciprocating engine, also called an engine or internal combustion engine, by means of 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 the respective combustion process, the respective fuel-air mixture, also simply called mixture, is combusted, from which the exhaust gases of the internal combustion engine are generated. As will also be explained in more detail below, the turbine can be driven by the exhaust gas. The mixture here at least comprises air and a fuel, in particular in liquid form. In particular the fuel is gasoline, i.e. a gasoline fuel. In this way, 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, which are fluidically separated from one another at least in partial regions. Each channel can be passed through by the exhaust gas. Furthermore, the turbine has a turbine wheel, which is in particular rotatably accommodated in the turbine housing. The turbine wheel can be driven by the exhaust gases and can thus, for example, rotate about a rotation axis relative to the turbine housing. In particular, the respective channels can be configured as respective spiral passages, which for example run at least substantially spirally over 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 of the turbine housing, which is also referred to as an accommodation area. In this case, for example, the respective channels communicate with the accommodation area, so that the exhaust gases flowing through the respective channels can be guided from the respective channels into the accommodation area and thus to the turbine wheel. In this way, the exhaust gases flowing through the respective channels leave the respective channels, enter the accommodation area and then impinge on the turbine wheel, thereby driving it.

[0006] The turbine, in particular the turbine housing, has at least one or just one bypass passage, via which at least a part 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 part 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 wastegate, wastegate passage, bypass or 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 the bypass passage, separate from the bypass passage or additionally provided 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 which is adjustable, i.e. movable, in particular 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 in particular completely closed, i.e. fluidically blocked, by the valve member, also called valve body. Thus, in the closed position, preferably no exhaust gas flows through the bypass passage, and in the closed position, preferably no exhaust gas flows 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 very particularly intended that in the closed position, the channels are in particular completely fluidically separated from one another. In the open position, the valve member opens both the bypass passage and the through-flow opening, in each case at least in a partial area, in particular simultaneously, so that in the open position, the exhaust gas can flow into 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 the through-flow openings being fluidically closed, i.e. fluidically blocked, by the valve member in the closed position, so-called dynamic 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 supercharging can be realized for supercharging the internal combustion engine.

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

[0011] In order to be able to fluidically connect the channels of the turbine in a particularly advantageous way and thus to realise a particularly advantageous channel connection, it is provided according to the invention that the valve member has at least one or exactly one flow passage which extends in particular completely through the valve member, in particular into the interior of the valve member, and through which the exhaust gas can flow, so that this flow passage is completely defined by the valve member (valve body), for example completely around its circumference, in particular over its entire extension in the flow direction of the exhaust gas flowing through the through-passage. The flow passage can be used, for example, for fluidically connecting the channels in addition to opening only a part of the through-flow opening in the open position. That is, in particular, if the valve member itself, for example, in the open position, opens a first partial area of ​​the through-flow opening and still projects into a second partial area of ​​the through-flow opening which is in particular adjacent to the first partial area, i.e. is arranged in the second partial area, the flow passage can be used to fluidically connect the channels to each other. In that 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 thus through part of the second partial region, so that, for example, a large volume flow and / or mass flow of the exhaust gas can be transferred from one of the channels to the respective other channel.

[0012] For example, the flow passage is formed by at least one or exactly one bore, whereby the flow passage can be realized in a particularly cost-effective manner. For example, the turbine is a segment turbine of at least two-channel type or exactly two-channel type, whereby a particularly advantageous or efficient operation can be realized. The invention here presupposes a channel connection already known from the prior art, which is variable in particular in that the through-flow opening can be completely fluidically blocked and thus closed by the movement of the valve member to a closed position, whereby the through-flow opening can be opened at least in a partial area by the movement of the valve member to an open position. In particular, it is conceivable that the valve member is adjustable, i.e. movable, to the closed position and to at least one of the above-mentioned open positions as well as to at least one or more further open positions, whereby in each further open position the through-flow opening is each opened at least in a partial area. In particular, in each open position, a respective volumetric and / or mass flow of exhaust gas can flow through the through-flow opening, whereby the volumetric and / or mass flows are different from one another in these open positions. This allows for a specially tailored, i.e. variable, connection of the channels, also called channel connection. The valve member is then given a double function. On the one hand, the valve member serves as a channel connection valve in order to selectively close or open the throughflow. On the other hand, the valve member serves as a wastegate valve or bypass valve in order to selectively open or close the bypass passage. The valve member then simultaneously defines, particularly in the respective open position, a first effective surface of the turbine wheel bypass and a second effective surface of the channel connection. The exhaust gases flow through the first effective surface and can enter the bypass passage via this. The exhaust gases also flow through the second effective surface and can thereby pass from one channel to the other. A turbine wheel bypass is understood to mean that at least a part 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 bounded 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 passing from one channel to the other. On the one hand, this allows for dynamic pressure charging to be realised, for example in the event of load jumps or when there are high requirements with regard to the transient behaviour of the internal combustion engine. On the other hand, the turbine can be operated with relatively good efficiency even at rated power. A characteristic feature 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, in particular of the outer circumferential side, of the valve member can then define the abovementioned surfaces and thus the area ratio and the resulting mass flow ratio of the exhaust gases as a function of the respective opening position and thus in particular as a function of the opening angle of the valve member, where the mass flow ratio is understood to be the ratio of a first mass flow to a second mass flow of exhaust gases, for example the first mass flow passing through the first surface or bypassing the turbine wheel and the second mass flow passing through the through-flow openings or transitioning from one channel to the other.

[0013] However, in the conventional methods, it is not possible to geometrically realize any arbitrary channel connection characteristic that is desirable from the engine point of view. Compared to the conventional solutions, the invention allows an improved, particularly tailored adaptation or adjustment of the mass flow ratio in the respective opening position. In particular, the invention expands the possibilities, in particular in terms of adapting the mass flow ratio in the respective opening position, so that not only the geometric clearance surface is changed, but also the effective flow surface. For this purpose, according to the invention, a flow passage, also called a through-flow passage, is formed in the valve member. The flow passage makes this possible, for example, even when the opening angle of the valve member is small, 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, in particular at the same time, but the through-flow opening is only slightly opened. This is possible, for example, in such a way that the first partial region mentioned above is opened, whereas the valve member itself is, for example, still arranged in the second partial region, so that the exhaust gas can flow through both the opened first partial region and the flow passage. As a result, a strong or extensive channel connection can be realized, despite 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, which can be transferred from one of the channels to the respective other channel, especially despite a small opening angle or even at a small opening angle of the valve member. Due to the kinematics of the valve member, a comparatively small channel connection mass flow can thus be produced even at a small opening angle, which mass flow increases significantly at a larger opening angle. The respective 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 passages are configured so that, for example, an additional connection mass flow of exhaust gas flowing through the flow passage can be activated using the main connection flow of exhaust gas flowing through the first partial region. In this way, the invention makes it possible to realize a desired or required channel connection characteristic and, for example, at the same time, advantageous, particularly advantageously small valve member sizes can be realized or maintained. As a result, a power gain can be realized without generating additional forces in the kinematics intended for the movement or position adjustment of the valve body. Kinematics intended for the position adjustment or movement of the valve member, in particular between the open and closed positions, include, for example, an electric adjustment member, also referred to as an E adjustment member. An electric adjustment member is an electrically actuable actuator, with which, for example, the valve member can be moved from the closed position to the open position and / or from the open position to the closed position using electrical energy.

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

[0016] Alternatively or additionally, it is provided that the flow passage has at least two length regions which extend obliquely or perpendicularly to one another 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, it is provided that the flow channel extends in an S- or Z-shape at least in partial regions, in particular in at least one or exactly one imaginary plane, so that the respective points at which the exhaust gases enter and exit the flow channel can be arranged in a particularly advantageous manner, and so that a particularly advantageous guidance of the exhaust gases can be realized.

[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 designed in such a way 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 and then through it and into the other channel via the flow passage, whereby the flow passages are particularly designed to guide the exhaust gas from one of the channels to the respective other channel in the open position. This allows particularly favorable operation to be realized, since even with a small opening angle, i.e. even with a small opening of the valve member, the channels can be fluidically connected to one another advantageously strongly.

[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 preferably provided that in the closed position the through-flow openings are particularly completely closed by the valve member and 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 it is possible to switch between a fluid connection of the channels and a fluid separation of the channels depending on the particular needs.

[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, so that it can be ensured in a particularly simple manner that in the closed position the exhaust gas cannot pass from one of the channels to the respective other channel, 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 defined switching 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 in particular completely fluidically separated from one another, can be performed, so that particularly advantageous operations can be realized.

[0022] A second aspect of the invention relates to an internal combustion engine, also referred to simply as internal combustion engine or engine, for example for a motor vehicle, consisting of a reciprocating engine, which has at least one exhaust gas turbocharger having a turbine according to the first aspect of the invention. Advantageous and advantageous configurations of the first aspect of the invention can be regarded as advantageous and advantageous configurations of the second aspect of the invention and vice versa.

[0023] Further advantages, features and details of the 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 invention. [Brief description 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; [Diagram 2] 2 shows another schematic perspective view of a turbine in part; [Diagram 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; [Diagram 5] FIG. 2 shows a schematic perspective view of a second embodiment of a valve member; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

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

[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 exactly four combustion chambers. Each combustion chamber is partially delimited by a respective cylinder. In each cylinder, a respective piston is accommodated for translational movement, and each combustion chamber is partially defined by the respective cylinder and partially by a piston accommodated for translational movement in the respective cylinder. During the combustion operation of the internal combustion engine, a combustion process takes place in the combustion chamber. In the respective combustion process, a fuel-air mixture, also simply called mixture, is burned. The respective mixture contains at least air and in particular liquid fuel. The internal combustion engine is preferably a gasoline engine. As a result of the respective combustion process, exhaust gases of the internal combustion engine are produced. The exhaust gases leave the respective combustion chamber and can flow into and through the exhaust gas installation of the internal combustion engine. Here, the turbine 10 of the exhaust gas turbocharger is arranged in the exhaust gas system, 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 is guided by it towards and into the combustion chamber. The air flowing through the intake manifold can be compressed by the compressor.

[0028] As can be seen from Figures 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 the exhaust gas can flow. In the exemplary embodiment shown in Figures 1 and 2, the turbine 10 is configured as a two-channel segment turbine. This is understood to mean that each channel 14, 16 has a respective outlet opening 18, 20 and communicates with an accommodation area 22 of the turbine housing 12 via the respective outlet opening 18, 20, the outlet openings 18 and 20 being arranged successively in the circumferential direction of the turbine 10, i.e. one behind the other. The turbine 10 furthermore has a turbine wheel 24 accommodated in the accommodation area 22 and thus in the turbine housing 12, whereby it is rotatable relative to the turbine housing 12 about an axis of rotation. The circumferential direction of the turbine 10 described above runs around said axis of rotation, so that the outlet openings 18 and 20 are arranged successively in the circumferential direction of the turbine wheel 24, seen over its circumference. Here, each channel 14, 16 is configured as a spiral passage. The channels 14 and 16 are fluidically separated from one another by a separating wall 26 in the turbine housing 12. In Fig. 1, arrow 28 designates a first flow of exhaust gases, in this example through channel 14. Arrow 30 designates a second flow of exhaust gases, through the turbine housing 12, which will also be described in more detail below.

[0029] The turbine 10, in particular the turbine housing 12, has a bypass passage, designated by the arrow 32, via which at least a part of the exhaust gas can be bypassed around the turbine wheel 24. As is evident from the arrow 32, the exhaust gas flowing through the bypass passage bypasses the turbine wheel 24 and therefore does not drive the turbine wheel 24. The exhaust gas flowing through the respective channel 14, 16 and guided by the respective channel 14, 16 into the receiving area 22 strikes the turbine wheel 24 and thereby drives it so that it rotates about its axis of rotation relative to the turbine housing 12. The compressor then has a compressor wheel arranged in the intake pipe, which can be driven by the turbine wheel 24, in particular via a shaft. By being driven, the compressor wheel can compress the air flowing through the intake pipe.

[0030] The turbine 10, in particular the turbine housing 12, in this example has exactly one through-flow opening 34 formed in the separating 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 called a valve body, which can be partially seen in Fig. 1. The valve member 36 is adjustable relative to the turbine housing 12 between a closed position, in particular completely closing the bypass passage and the through-flow opening 34, respectively, and at least one open position, which is clearly shown in Figs. 1 and 2, in which the bypass passage and the through-flow opening 34, respectively, are opened at least in a partial area. With reference to the arrows 28 and 32 and also with reference to the 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 part 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, after which the first part flows through the channel 16 and is guided by the channel 16 into the receiving area 22 and therewith to the turbine wheel 24. The second part of the exhaust gases, which first flows through the channel 14, remains in the channel 14 and is guided by the channel 14 towards the receiving area 22 and therein to the turbine wheel 24. The first part of the exhaust gases is designated by the arrow 38, and the second part by the arrow 28. It is designated by the arrow 32 that, for example, the third part of the exhaust gases, which first flows through the channel 14, flows from the channel 14, in particular via the through-flow opening 34, into the bypass passage and then flows through the bypass passage and thereby bypasses the turbine wheel 24, due to the valve member 36 being in the open position. In the closed position, the through-flow opening 34 is in particular completely closed by the valve member 36 and thus completely fluidically blocked, and it is preferably intended that in the closed position the bypass passage is completely closed by the valve member 36, i.e. completely fluidically blocked. In the open position, the valve member 36 opens both the through-flow opening 34 and the bypass passage, respectively, at least in a partial area.

[0032] The turbine 10 then has an actuator 40, also called adjustment member, which is shown separately and diagrammatically in Figure 1, by means of which the valve member 36, for example in the closed position, can be moved to an open position and / or from the open position to the closed position relative to the turbine housing 12. For example, the actuator 40 is an electric actuator, i.e. an electrically actuable actuator, for which reason the actuator 40 is also called E adjustment member. Very preferably, the valve member 36 is intended to simultaneously, respectively at least partially open both the bypass passage and the through-flow opening 34 when it is adjusted from the closed position to the open position.

[0033] In order to be able to realise a particularly advantageous fluid connection of the channels 14 and 16, also called channel connection, the valve member 36, as can be seen very clearly in the joint view of Figures 4 and 5, has at least one, or as intended in Figures 4 and 5 exactly one, flow passage 44 which in particular passes completely through the valve member 36 and thus extends into the interior of the valve member 36 and through which the exhaust gases can flow as indicated by the arrow 42 in Figure 4, and which is in particular completely defined by the valve member 36 in such a way that it goes completely around the circumference of the flow passage 44, in particular over the entire extent of its extension into the interior of the valve member 36. The arrow 42 in Figure 4 indicates the flow of the exhaust gases 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, in particular about a pivot axis. The valve member 36 can thus be pivoted, for example, into different angular positions or angular attitudes, also called pivot positions. One of these angular positions, in particular exactly one, is the closed position. The remaining or all remaining pivot positions, also called opening angles, are opening positions, in which the valve member 36 opens both the bypass passage and the through-flow opening 34, in particular simultaneously. In particular in the case of a small opening angle, 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, which is in particular adjacent to the first partial area, so that the valve member 36 is still arranged in the second partial area in the case of a small opening angle. 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 area of ​​the through-flow passage 34, and the second partial area 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 has a flow passage 44, which extends, for example, from its first end E1 to its second end E2. Here, by way of example, in particular in the case of a small opening angle, the end E1 is arranged in the second partial area of ​​the through-flow opening 34, 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, via the open first partial region, but the exhaust gas can also flow through the flow passage 44 and thus flow from one of the channels 14 and 16 to the other channel 16 or 14, respectively, via the flow passage 44.The flow passage 44 is thus a fluid connection between the channels 14 and 16 that is, so to speak, provided in addition to the open first partial region, so that, for example, a large exhaust gas mass flow can transfer between the channels 14 and 16, in particular 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 arranged on an axial end face 46 of the valve member 36.

[0036] Usually, and especially when there are no flow passages in the valve member 36, such as the flow passage 44, through which the exhaust gases can flow, the contour, in particular the only one, in particular the outer circumference, of the valve member 36, also called valve body, defines the ratio, also called the mass flow ratio, of the first mass flow of exhaust gases flowing through the bypass passage in the open position and the second mass flow of exhaust gases flowing through the through-flow opening 34 in the open position. The mass flow ratio is then determined as a function of the respective opening angle of the valve member 36. However, in the conventional manner, any arbitrary channel connection characteristic that is desirable from the engine point of view cannot be generated geometrically, i.e. by the contour of the valve member 36. 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 with regard to the opening and closing of the bypass passages and the channel connections. In particular the opening kinematics for adjusting the position of the valve member 36, the shape of the outer circumference and therefore the subsequent change in the contour of the outer circumference of the valve member 36 directly influence the required protection range. Valve member 36 is therefore given special significance in defining the channel connections and particularly its properties.

[0037] In the engine process simulation, the engine targets can be connected to a target curve of the channel connection characteristic. Such a target curve, also simply called a curve, often indicates a wide adjustment range of the valve member 36, in which the connection surface of the through-flow opening 34, also called the channel connection surface, increases. In contrast, the second surface, also called the wastegate surface, through which the exhaust gases can flow into the bypass passage, increases significantly only when the opening angle of the valve member 36 increases. If, for example, the means for adjusting the valve member 36 have been exhausted and an increase in the size of the valve member 36 as a whole becomes unreasonable, it is no longer possible to further increase the channel connection surface at the current level. For this reason, 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 that case, it should be excluded that additional structural elements have an influence on the channel connection characteristic when the valve member 36 is closed, i.e. in the closed position. Simulations show that, despite the complex and expensive 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 it may not be possible to utilize the entire partial area of ​​the through-flow openings 34 released by the valve member 36 in the respective open position for the fluid connection of the channels 14 and 16. This may be due to a non-optimal flow guidance towards the valve member 36, particularly in the case of small design dimensions of the exhaust gas turbocharger.

[0038] An at least approximately exact optimization of the channel connection can be achieved by providing at least one or exactly one flow passage 44 in the valve member 36. By providing the flow passage 44 in the valve member 36, a new cross section is made available for the channel connection 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 area 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 the end E2 is the outlet of the passage, the discharge from which takes place, for example in the first embodiment, at the level of the separating web. This makes it possible to eliminate the fluid connection between the channels 14 and 16 when the valve member 36 is in the closed position, in particular because the end E2 and thus the flow passage 44 are closed, i.e. fluidically blocked, in the closed position, in particular because the axial end face 46 and thus the end E2 in particular directly abuts against the corresponding wall area of ​​the turbine housing 12 in the closed position. In this way, for example in particular the entire outlet (end E2) is closed by the wall area. It has further been found that by using the locally high velocities or the resulting low static pressures at the separating web, it is possible to guide as large as possible a mass flow from the active channels 14, 16 to the passive channels 16, 14. Active and passive channels are understood in particular as follows: That is, at least one first combustion chamber, in particular at least two or exactly two first combustion chambers, is assigned to the channel 14 and in particular fluidically connected to the channel 14, and at least one second combustion chamber, in particular at least two or exactly two second combustion chambers, is assigned to the channel 16 and in particular fluidically connected to the channel 16. The exhaust gas from the first combustion chamber, in particular with respect to the channels 14 and 16, firstly flows only into the channel 14 but not into the channel 16. The exhaust gas from the second combustion chamber, in particular with respect to the channels 14 and 16, firstly flows only into the channel 16 but not into the channel 14. In FIG. 1, the channel 14 is the active channel and the channel 16 is the passive channel, since, for example, with respect to the first and second combustion chambers, only the exhaust gas of the first combustion chamber is provided. Thus, the exhaust gas from the first combustion chamber first flows into the channel 14 and, when the valve member 36 is in the open position, at least partially flows from the channel 14 into the channel 16. In FIG. 2, channel 16 is the active channel, whereas channel 14 is the passive channel.Since 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, the exhaust gas from the second combustion chamber first flows into the channel 16 and then, when the valve member 36 is in the open position, at least partially leaves the channel 16 at point S and flows into the channel 14. In FIG. 2 as in FIG. 1, the arrows 28 indicate the exhaust gases that first flow into the active channel, remain there, and are passed by the active channel towards the receiving area 22 and therein, and thus guided to the turbine wheel 24. In FIG. 2 as in FIG. 1, the arrows 38 indicate the exhaust gases that first flow into the active channel, but do not remain there, but flow through the at least partially opened through-flow openings 34 at point S, thus passing from the active channel to the passive channel. Furthermore, in FIG. 2 as in FIG. 1, the arrows 32 indicate the exhaust gases that flow through the bypass passage.

[0040] And, in particular for the exhaust gases from the active channels, not only the first partial area, which is freed in the respective open position, but also the flow passage 44 can be utilized for the transition from the active to the passive channels, so that even with a small opening angle, a large mass flow of exhaust gases passing from the active to the passive channels can be realized. In comparison with a valve member 36 without the flow passage 44, a clear increase in the channel connection, i.e. the mass flow of exhaust gases passing from the active to the passive channels, can be seen. In particular, the provision of the flow passage 44 allows the turbine power to be increased while the position of the valve member 36 remains the same.

[0041] For example, the valve member 36 itself is of solid design and in this example comprises 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 a particularly advantageous channel connection to be realized. In the closed position, the flow passage 44 does not create a fluid connection between the channels 14 and 16. In the open position, however, the flow passage 44 creates a fluid connection between the channels 14 and 16 that is provided in addition to the first open partial area, and thus creates an additional mass flow, also called a channel connection mass flow, of exhaust gas passing from the active channels to the passive channels, which additional channel connection mass flow is in addition to the mass flow of exhaust gas flowing through the first open partial area. The additional flow passage 44 can be formed by a single bore or by several 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 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 the end E1, through which exhaust gas can enter the flow passage 44 from the respectively active channel, is directly in the transitioning exhaust gas or in its flow when exhaust gas is flowing in the respectively active channel and thus in 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 directly into the flow passage 44. An outlet of the flow passage 44, for example provided at and formed by the end E2, is, for example, at such a point of the valve member 36, which 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 and in the closed position rests directly against a wall, also called wall area, formed for example by a housing in which the valve member 36 is arranged, for example the turbine housing 12 or a further 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) with at least two channels (14, 16), which are fluidically separated from one another at least in partial regions and through which exhaust gases of an internal combustion engine can flow, a turbine wheel (24) accommodated in the turbine housing (12) and drivable by the exhaust gases, at least one bypass passage (32) through which the turbine wheel (24) can be bypassed by at least a portion of the exhaust gases, and a turbine wheel (24) for connecting the channels (14, 16) to one another. the turbine (10) having at least one through-flow opening (34) fluidly connectable to a bypass passage (32) and having at least one valve member (36) which is positionable 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) passing through the valve member (36) and through which the exhaust gas can flow, 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- or Z-shape at least in partial regions.

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

3. 3. The turbine (10) according to claim 1 or 2, characterized in that in the closed position, the fluid connection between the channels (14, 16) created by the flow passage (44) is prevented.

4. The turbine (10) of claim 3, wherein the flow passage (44) is fluidly blocked by a wall region of the turbine housing (12) in the closed position.

5. 5. The turbine (10) according to any one of the preceding claims, characterized in that in the closed position, the through-flow opening (34) is completely closed by the valve member (36).

6. 6. An internal combustion engine for a motor vehicle, comprising at least one exhaust gas turbocharger comprising a turbine (10) according to any one of claims 1 to 5.

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