Exhaust manifold system for turbocharger device with plural volute members

A turbocharger system includes a manifold system that maintains separation between flow paths of different manifold arrangements. One manifold arrangement directs flow from a first group of combustion chambers to a first volute passage of a turbine section of a turbocharger. Another manifold arrangement directs flow from a second group of combustion chambers to a second volute passage of the turbine section of the turbocharger. The system also provides selective variation of the available volume for exhaust flow through the manifold arrangements.

TECHNICAL FIELD

The present disclosure generally relates to a turbocharger system and, more particularly, relates to an exhaust manifold system for a turbocharger device with plural volute members.

BACKGROUND

Some engine systems include one or more turbochargers. Typically, turbochargers include a turbine wheel and a compressor wheel mounted on a common shaft and carried within isolated turbine and compressor housings, respectively. The turbine wheel may be driven in rotation by exhaust gas output by the engine. This, in turn, rotates the compressor wheel for compressing air that is fed to the combustion chambers of the engine. Accordingly, the turbocharger may provide a performance boost and increased efficiency to the engine.

Turbocharger systems may operate in a number of conditions. For example, the turbocharger may operate at relatively low engine speeds, relatively high engine speeds, and at speeds therebetween. As such, the turbocharger system may operate at times when the exhaust mass flow is relatively high, low, and therebetween.

Accordingly, it is desirable to provide an improved turbocharger system that boosts engine performance across a wide range of operating conditions. Other desirable features and characteristics of the present disclosure will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and this background discussion.

BRIEF SUMMARY

In one embodiment, a turbocharger system is disclosed that is configured to receive exhaust gas from an engine with a plurality of combustion chambers. The turbocharger system includes a turbine section with a turbine wheel, a first volute member with a first volute passage, and a second volute member with a second volute passage. The first volute passage is configured to direct flow of exhaust gas toward the turbine wheel, and the second volute passage configured to direct flow of exhaust gas toward the turbine wheel. A manifold system is included that is configured to route exhaust gas from the plurality of combustion chambers to the first volute passage and the second volute passage. The manifold system includes a first manifold arrangement and a second manifold arrangement. The first manifold arrangement is configured to receive a first exhaust gas from a first group of the plurality of combustion chambers and direct the first exhaust gas to the first volute member. The second manifold arrangement is configured to receive a second exhaust gas from a second group of the plurality of combustion chambers and direct the second exhaust gas to the second volute member. The first manifold arrangement is fluidly disconnected from the second manifold arrangement. The first manifold arrangement includes a first manifold and a second manifold. The first manifold and the second manifold are fluidly connected to the combustion chambers of the first group and to the first volute member. The first manifold arrangement is configured to operate in a first condition and a second condition of the turbocharger system. In the first condition, the first manifold arrangement is configured to direct flow of the first exhaust gas from the first group to the first volute member via the first manifold. In the second condition, the first manifold arrangement is configured to direct flow of the first exhaust gas from the first group to the first volute member via the first manifold and the second manifold.

In another embodiment, a method of operating a turbocharger system is disclosed that includes determining, by a processor, a characteristic of the turbocharger system. The characteristic is related to the flow of exhaust gas from a plurality of combustion chambers of an engine via a manifold system to a first volute member and a second volute member of a turbine section of a turbocharger. The method also includes selectively controlling, by the processor, a valve between a first position and a second position based on the determined characteristic to change flow through the manifold system. The manifold system includes a first manifold arrangement and a second manifold arrangement. The first manifold arrangement is configured to receive a first exhaust gas from a first group of the plurality of combustion chambers and direct the first exhaust gas to the first volute member. The second manifold arrangement is configured to receive a second exhaust gas from a second group of the plurality of combustion chambers and direct the second exhaust gas to the second volute member. The first manifold arrangement is fluidly disconnected from the second manifold arrangement. The first manifold arrangement includes a first manifold and a second manifold that are fluidly connected to the combustion chambers of the first group and to the first volute member. In the first position of the valve, the first manifold arrangement is configured to direct flow of the first exhaust gas from the first group to the first volute member via the first manifold. In the second position of the valve, the first manifold arrangement is configured to direct flow of the first exhaust gas from the first group to the first volute member via the first manifold and the second manifold.

In a further embodiment, a turbocharger system is disclosed that includes an engine with a plurality of combustion chambers configured to produce an exhaust gas. The turbocharger system also includes a turbocharger with a turbine housing having a first scroll and a second scroll. A manifold system is included that is configured to route the exhaust gas from the plurality of combustion chambers to the first scroll and the second scroll. Moreover, the turbocharger system includes a valve having a first position and a second position. The turbocharger system additionally includes a controller configured to detect an operation characteristic of the engine and selectively change the valve between the first position and the second position based on the detected operation characteristic. The manifold system includes a first manifold arrangement and a second manifold arrangement. The first manifold arrangement is configured to receive a first exhaust gas from a first group of the plurality of combustion chambers and direct the first exhaust gas to the first scroll. The second manifold arrangement is configured to receive a second exhaust gas from a second group of the plurality of combustion chambers and direct the second exhaust gas to the second scroll. The first manifold arrangement is fluidly disconnected from the second manifold arrangement. The first manifold arrangement includes a first manifold and a second manifold. The first manifold and the second manifold fluidly are connected to the combustion chambers of the first group and to the first scroll. When the valve is in the first position, the first manifold arrangement is configured to direct flow of the first exhaust gas from the first group to the first scroll via the first manifold. In addition, when the valve is in the second position, the first manifold arrangement is configured to direct flow of the first exhaust gas from the first group to the first scroll via the first manifold and the second manifold.

DETAILED DESCRIPTION

Broadly, example embodiments disclosed herein include a turbocharger system with improved characteristics. In particular, example embodiments include a turbocharger system with at least two volute members (e.g., scrolls) and an exhaust manifold system configured to direct exhaust gas flow from a plurality of engine combustion chambers to the volute members. In particular, the manifold system may define a first manifold arrangement and a second manifold arrangement. The first manifold arrangement may receive exhaust gas from a first group of the engine combustion chambers and direct the flow to a first volute member. The second manifold arrangement may receive exhaust gas from a second group of the engine combustion chambers and direct the flow to a second volute member. The first manifold arrangement may be fluidly disconnected from the second manifold arrangement.

In some embodiments, the first manifold arrangement may include a first manifold and a second manifold. Under some operating conditions (e.g., at relatively low engine speeds), exhaust may flow via the first manifold from the first group of combustion chambers to the first volute member. In other operating conditions (e.g., at relatively high engine speeds), exhaust may flow via the first and second manifolds from the first group of combustion chambers to the first volute member.

Furthermore, in some embodiments, the second manifold arrangement may include features that are similar to the first manifold arrangement. Accordingly, the second manifold arrangement may include a first manifold and a second manifold. Under some operating conditions, exhaust may flow via the first manifold from the second group of combustion chambers to the second volute member. In other operating conditions, exhaust may flow via the first and second manifolds from the second group of combustion chambers to the second volute member.

Accordingly, the available volume for exhaust gas flow through the first and second manifold arrangements may be selectively changed, for example, based on current operating conditions. In addition, the first manifold arrangement and the second manifold arrangement may remain fluidly disconnected from each other at the different operating conditions. As such, the manifold system of the present disclosure may provide increased efficiency at some operating conditions (e.g., low engine speeds) due to the separate flow paths from the combustion chambers to the respective volute members. Also, the manifold system may allow the available volume for exhaust gas to be selectively increased at other operating conditions (e.g., high engine speeds) to maintain operating efficiency.

Methods of operating the manifold system will also be discussed. In some embodiments, valves may be included for controlling flow through the first and/or second manifold arrangements.

FIG. 1is a schematic view of an example turbocharger system100that includes a turbocharger housing101and a rotor102. The rotor102is configured to rotate within the turbocharger housing101about an axis103(axis of rotor rotation). The rotor102may be supported for rotation about the axis103via one or more bearings (not shown). In some embodiments, the rotor102may be rotationally supported by thrust bearings and a plurality of journal bearings. Alternatively, other bearings may be included.

As shown in the illustrated embodiment, the turbocharger housing101may include a turbine housing105, a compressor housing107, and a bearing housing109. The bearing housing109may be disposed between the turbine and compressor housings105,107. Also, in some embodiments, the bearing housing109may contain the bearings of the rotor102.

Additionally, the rotor102includes a turbine wheel111, a compressor wheel113, and a shaft115. The turbine wheel111is located substantially within the turbine housing105. The compressor wheel113is located substantially within the compressor housing107. The shaft115extends along the axis103, through the bearing housing109, to connect the turbine wheel111to the compressor wheel113. Accordingly, the turbine wheel111and the compressor wheel113may rotate together about the axis103.

The turbine housing105and the turbine wheel111cooperate to form a turbine (i.e., turbine section, turbine stage) configured to circumferentially receive a high-pressure and high-temperature exhaust gas stream (collectively referred to with reference number121) from a plurality of combustion chambers124of an internal combustion engine125. The exhaust gas stream121may be delivered via an exhaust manifold system191. As will be discussed in detail below, the exhaust manifold system191may include one or more structures that include two or more exhaust passages, pathways, lines, etc. for routing exhaust gas from the plurality of combustion chambers124to the turbine housing105.

The turbine wheel111(and thus the rotor102) is driven in rotation around the axis103by the high-pressure and high-temperature exhaust gas stream121. The turbine housing105may also be connected to a downstream exhaust structure126(e.g., one or more downstream exhaust pipes). The turbine housing105may release an exhaust gas stream127thereto. The exhaust gas stream127can be lower-pressure and lower-temperature compared to the exhaust gas stream121.

Also, in some embodiments, the turbine housing105may include one or more structures that define distinct flow passages for exhaust gas delivered by the manifold system191. As shown schematically in the embodiment ofFIG. 1, the turbine housing105may include a first member196(e.g., a first scroll structure) and a second member198(e.g., a second scroll structure). The first and/or second members196,198may define distinct volute passages (i.e., volute flow paths) that spiral about the axis103and about the turbine wheel111. As such, the first and second members196,198may comprise a twin scroll arrangement of the turbine housing105. It will be appreciated that the first member196and the second member198may be constructed from two parts that are removably attached. In other embodiments, the first member196and the second member198may be integrally connected and may define a unitary, one piece structure. Furthermore, it will be appreciated that the turbine housing105may include more than two volute passages without departing from the scope of the present disclosure.

The compressor housing107and compressor wheel113cooperate to form a compressor (i.e., compressor section, compressor stage). The compressor wheel113, being driven in rotation by the exhaust-gas driven turbine wheel111, is configured to compress received input air131(e.g., ambient air, or already-pressurized air from a previous-stage in a multi-stage compressor) into a pressurized air stream133that is ejected circumferentially from the compressor housing107. The compressor housing107may have a shape (e.g., a volute shape or otherwise) configured to direct and pressurize the air blown from the compressor wheel113. Due to the compression process, the pressurized air stream is characterized by an increased temperature, over that of the input air131.

The air stream133may be channeled through an air cooler135(i.e., an intercooler), such as a convectively cooled charge air cooler. The air cooler135may be configured to dissipate heat from the air stream133, increasing its density. The resulting cooled and pressurized air stream137is channeled into an intake manifold139of the internal combustion engine125, or alternatively, into a subsequent-stage, in-series compressor.

The operation of the system may be controlled by an engine control unit (ECU)151that connects to the remainder of the system via communication connections153. The ECU151may include a processor199, which is connected to one or more sensors189. The sensor189may be configured to detect various conditions relating to the turbocharger system100. In some embodiments, for example, the sensor189may detect various conditions related to the operation of the engine125(e.g., engine speed, exhaust gas mass flow output, etc.). The sensor189may provide signals to the processor199that correspond to the detected condition(s). The processor199may, in turn, process the signal(s) and generate control signals for controlling elements of the system100as will be discussed in detail below. In some embodiments, the processor199and/or sensor189may rely on a virtual sensor or predetermined model for detecting the operating conditions of the engine125and controlling the system100.

It will be appreciated that the turbocharger system100and the valve structure190may be arranged and configured differently from the embodiment ofFIG. 1without departing from the scope of the present disclosure. Moreover, it will be appreciated thatFIG. 1schematically illustrates the turbocharger system100, the manifold system191, the IC engine125, and other components. Therefore, these components are not necessarily drawn to scale, connections between parts are shown conceptually, etc.

Referring now toFIG. 2, additional details are shown. As shown, the engine125may include a plurality of combustion chambers124. There may be any number of combustion chambers124, and the combustion chambers124may have a variety of configurations (e.g., a V-configuration, a straight-configuration, a flat-configuration, etc.) without departing from the scope of the present disclosure.

As shown, the engine125may be a six-cylinder engine in some embodiments such that the plurality of combustion chambers124includes a first chamber202, a second chamber204, a third chamber206, a fourth chamber208, a fifth chamber210, and a sixth chamber212. The first, second, and third chambers202,204,206may comprise a first group of chambers207. The fourth, fifth, and sixth chambers208,210,212may comprise a second group of chambers213. In some embodiments, the first group of chambers207may be positioned in the engine125in an area that is opposite that of the second group of chambers213. For example, the first group of chambers207may be positioned generally in the front of the engine125while the second group of chambers213may be positioned generally in the rear of the engine125.

Also, during operation, the combustion chambers124may have a predetermined firing order (i.e., sequence of power delivery from each chamber124). It will be appreciated that the firing order may be achieved by controlled sparking of spark plugs for the respective chambers124, or in the case of a diesel engine, by controlling the sequence of fuel injection into the chambers124. In some embodiments, the combustion chambers124may have the following sequential firing order: the first chamber202, the fifth chamber210, the third chamber206, the sixth chamber212, the second chamber204, and then the fourth chamber208. However, it will be appreciated that the firing order may be different without departing from the scope of the present disclosure.

Additionally, the first combustion chamber202may include a first exhaust port232and a second exhaust port233. Accordingly, in some embodiments, the first combustion chamber202may include dual exhaust ports. The first exhaust port232and the second exhaust port233may be configured for exhausting gas from the first combustion chamber202and delivering the exhaust gas to the exhaust manifold system191.

Flow through the first exhaust port232may be controlled by a first engine valve235. The first engine valve235may be a conventional valve that is supported by the engine125(e.g., proximate the cylinder head). The first engine valve235may move between a CLOSED position and an OPEN position. Also, the position of the first engine valve235may be controlled by the ECU151in some embodiments. The second exhaust port233may also include a second engine valve237, which may be substantially similar to the first engine valve235.

Like the first combustion chamber202, the second combustion chamber204may respectively include a first exhaust port236and a second exhaust port239. Also, the third combustion chamber206may respectively include a first exhaust port240and a second exhaust port241. Also, like the first exhaust port232, the first exhaust ports236,240may include respective first engine valves235. Moreover, like the second exhaust port233, the second exhaust ports239,241may include respective second engine valves237.

Similarly, the fourth combustion chamber208may include a first exhaust port266and a second exhaust port268. The fifth combustion chamber210may include a first exhaust port270and a second exhaust port272. Also, the sixth combustion chamber212may include a first exhaust port274and a second exhaust port276. Like the first exhaust port232of the first combustion chamber202, the first exhaust ports266,270,274may include respective first engine valves235. Moreover, like the second exhaust port233of the first combustion chamber202, the second exhaust ports268,272,276may include respective second engine valves237.

FIG. 2also shows the turbine housing of the turbocharger system100. As mentioned above with reference toFIG. 1, the turbine housing105may include the first member196(e.g., first scroll) and the second member198(e.g., second scroll). The first member196may define a first volute passage214, and the second structure198may define a second volute passage216for the turbocharger system100.

The manifold system191may include a first manifold arrangement218. The first manifold arrangement218may include one or more structures (e.g., pipes, conduits, lines, etc.). The first manifold arrangement218may be configured to route exhaust gas from the first group207of the combustion chambers124to the first member196and the first volute passage214therein.

The manifold system191may also include a second manifold arrangement222. The second manifold arrangement222may include one or more structures (e.g., pipes, conduits, lines, etc.). The second manifold arrangement222may be configured to route exhaust gas from the second group213of the combustion chambers124to the second structure198and the second volute passage216therein.

As shown inFIG. 2, the first manifold arrangement218may be fluidly disconnected from the second manifold arrangement222. As such, flow from the first group207of combustion chambers124to the first volute passage214may be independent of the flow from the second group213of combustion chambers124to the second volute passage216.

The first manifold arrangement218may include a number of manifold structures, branches, lines, etc. for fluidly connecting to the combustion chambers124of the first group207and for fluidly connecting to the first volute passage214. For example, the first manifold arrangement218may include a first manifold226and a second manifold228.

The first manifold226may include a first segment230that is fluidly connected to the first exhaust port232of the first chamber202, a second segment234that is fluidly connected to the first exhaust port236of the second chamber204, and a third segment238that is fluidly connected to the first exhaust port240of the third chamber206. The first segment230, the second segment234, and the third segment238may be joined at a first fluid junction242. The first manifold226may additionally include an intermediate segment244that extends away from the first fluid junction242and that directs the exhaust gas in a downstream direction therefrom.

The second manifold228may include a first segment246that is fluidly connected to the second exhaust port233of the first chamber202, a second segment250that is fluidly connected to the second exhaust port239of the second chamber204, and a third segment254that is fluidly connected to the second exhaust port241of the third chamber206. The first segment246, the second segment250, and the third segment254may be joined at a second fluid junction258. The second manifold228may additionally include an intermediate segment260that extends away from the second fluid junction258and that directs the exhaust gas in a downstream direction therefrom.

In some embodiments, the first manifold226and the second manifold228may be fluidly connected at a third fluid junction262, which may be disposed upstream of the first volute passage214. Moreover, the first manifold arrangement218may include a common segment264. The common segment264may be fluidly connected to the third fluid junction262and the first volute passage214. It will be appreciated that the third fluid junction262and the common segment264are optional components and that the first and second manifolds226,228may fluidly connect to the first member196independent of each other.

The second manifold arrangement222may include a number of manifold structures, branches, lines, etc. for fluidly connecting to the combustion chambers124of the second group213and for fluidly connecting to the second volute passage216. For example, the second manifold arrangement222may include a first manifold278and a second manifold280.

The first manifold278may include a first segment282that is fluidly connected to the first exhaust port266of the fourth chamber208, a second segment284that is fluidly connected to the first exhaust port270of the fifth chamber210, and a third segment286that is fluidly connected to the first exhaust port274of the sixth chamber212. The first segment282, the second segment284, and the third segment286may be joined at a fourth fluid junction288. The first manifold278may additionally include an intermediate segment290that extends away from the fourth fluid junction288and that directs the exhaust gas in a downstream direction therefrom.

The second manifold280may include a first segment281that is fluidly connected to the second exhaust port268of the fourth chamber208, a second segment283that is fluidly connected to the second exhaust port272of the fifth chamber210, and a third segment285that is fluidly connected to the second exhaust port276of the sixth chamber212. The first segment281, the second segment283, and the third segment285may be joined at a fifth fluid junction292. The second manifold280may additionally include an intermediate segment294that extends away from the fifth fluid junction292and that directs the exhaust gas in a downstream direction therefrom.

In some embodiments, the first manifold278and the second manifold280may be fluidly connected at a sixth fluid junction296, which may be disposed upstream of the second volute passage216. Moreover, the first manifold arrangement218may include a common segment298. The common segment298may be fluidly connected to the sixth fluid junction296and the second volute passage216. It will be appreciated that the sixth fluid junction296and the common segment298are optional components and that the first and second manifolds278,280may fluidly connect to the second member198independent of each other.

Furthermore, the manifold system191may include one or more valves. For example, a first valve297(i.e., first backflow valve) may be included. The first valve297may be operably supported, for example, on the intermediate segment260of the second manifold228of the first manifold arrangement218. Also, a second valve299(i.e., second backflow valve) may be included. The second valve299may be operably supported, for example, on the intermediate segment294of the second manifold280of the second manifold arrangement222.

The first valve297and/or the second valve299may be one-way valves that are moveable between an open position and a closed position. With the first valve297in the open position, exhaust gas may flow in the downstream direction through the second manifold228. Also, with the first valve297in the closed position, exhaust gas may be inhibited from flowing through the second manifold228in the upstream direction (i.e., from the common segment264toward the engine125). Similarly, with the second valve299in the open position, exhaust gas may flow in the downstream direction through the second manifold280. Also, with the second valve299in the closed position, exhaust gas may be inhibited from flowing through the second manifold280in the upstream direction (i.e., from the common segment298toward the engine125).

In some embodiments, the first valve297and/or the second valves299may be passive valves, such as a one-way reed valve. The first valve297and/or second valve299may also operate in a coordinated fashion with the second engine valves237of the second exhaust ports233,239,241,268,272,276. Generally, in some embodiments, the second engine valves237may be actively controlled (e.g., by the ECU151) according to one or more variable conditions of the engine125to regulate exhaust flow through the second manifolds228,280. Accordingly, in some conditions, the ECU151may control the second valves237to open during the exhaust cycles of the combustion chambers124so that exhaust gas flows into the second manifolds228,280. Pressure from these exhaust streams may passively open the first and second valves297,299for flow toward the first and second volute passages214,216. In other conditions, the ECU151may control the second valves237to remain closed during the exhaust cycles of the combustion chambers124so that exhaust is prevented from flowing downstream along the second manifolds228,280; additionally, the first and second valves297,299may passively remain closed due to the higher pressure downstream (e.g., in the common segments264,298), thereby preventing backflow into the second manifolds228,280.

It will be appreciated that the first valve297and/or second valve299may be configured differently without departing from the scope of the present disclosure. For example, the first and second valves297,299may be active valves (e.g., rotary valves) with an associated actuator that may be controlled by the ECU151. In addition, it will be appreciated that the first and second valves297,299are optional and may be omitted without departing from the scope of the present disclosure.

Referring now toFIG. 3, a method300of operating the turbocharger system100will now be discussed. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed. The method300may begin at301(e.g., upon engine startup).

Then, at302, the sensor189may detect a characteristic, such as the speed of the engine125, the exhaust mass flow or other characteristic related to exhaust flow from the engine125. The sensor189may send an associated signal to the processor199. The processor199may process the signal and, at304, the processor199may determine whether the detected current engine speed is greater than a predetermined threshold (e.g., threshold engine speed X). The threshold speed X may have any suitable value and may be stored, for example, in a data storage device.

If the detected engine speed is less than the threshold speed X (i.e.,304answered negatively), the method may continue at306. At306, the processor199may generate and send control signals to the engine125such that the first engine valves235open during the respective exhaust cycle of the combustion chambers124. At306, control signals may also cause the second engine valves237to remain in the closed position. Accordingly, exhaust from the first group207of the combustion chambers124may flow to the first volute passage214via the first manifold226. There may be substantially no exhaust flow through the second manifold228because the second engine valves237remain closed, and the first valve297may remain closed to prevent backflow through the second manifold228. Likewise, exhaust from the second group213of the combustion chambers124may flow to the second volute passage216via the first manifold278, and there may be substantially no exhaust flow through the second manifold280.

If, however, the detected engine speed is higher than the threshold speed X (i.e.,304answered affirmatively), the method may continue at308. At308, the processor199may generate and send control signals to the engine125such that the first engine valves235and the second engine valves237open during the respective exhaust cycle of the combustion chambers124. Accordingly, exhaust from the first group207of the combustion chambers124may flow to the first volute passage214via the first manifold226and the second manifold228. Likewise, exhaust from the second group213of the combustion chambers124may flow to the second volute passage216via the first manifold278and the second manifold280.

The method300may end at310(e.g., when the engine is turned off). It will be appreciated that the method300may repeat continuously until the engine is turned off. Thus, the engine speed may be continuously and repeatedly sensed, and operation of the turbocharger system100and the manifold system191may be operated accordingly.

Referring now toFIG. 4, the turbocharger system100is illustrated according to additional embodiments. The turbocharger system100may be substantially similar to the embodiments ofFIG. 2except as noted. Components that correspond to those ofFIG. 2are indicated with corresponding reference numbers increased by 200.

As shown, the engine325may include a first chamber402, a second chamber404, a third chamber406, and a fourth chamber408. Accordingly, the engine325may be a four-cylinder engine. In some embodiments, the first and second chambers402,404may be positioned in the engine325in an area that is opposite that of the third and fourth chambers406,408. For example, the first and second chambers402,404may be positioned generally in the front of the engine325while the third and fourth chambers406,408may be positioned generally in the rear of the engine325. In some embodiments, the firing order of the combustion chambers324may have the following sequence: first chamber402, third chamber406, fourth chamber408, and then second chamber404.

The manifold system391may include a first manifold arrangement418and a second manifold arrangement422. The first manifold arrangement418may include the first manifold426and the second manifold428, and the second manifold arrangement422may include the first manifold478and the second manifold480. These components may be substantially similar to the embodiments discussed above, except the connections to the combustion chambers324may be different.

The first manifold arrangement418may fluidly connect the first group407of combustion chambers324to the first volute passage214. The second manifold arrangement422may fluidly connect the second group413of combustion chambers324to the second volute passage216. In the embodiment shown, the first group407may include the first chamber402and the fourth chamber408, and the second group413may include the second chamber404and the third chamber406. As such, the first manifold arrangement418may be fluidly connected to combustion chambers324with nonconsecutive firing orders. Likewise, the second manifold arrangement422may be fluidly connected to combustion chambers324with nonconsecutive firing orders.

The turbocharger system100ofFIG. 4may operate as discussed above. For example, in some embodiments, the turbocharger system100ofFIG. 4may operate according to the method300ofFIG. 3and described above.

In summary, the turbocharger system100and method300of the present application provide efficient and effective operations. The system100may maintain separation between the flow paths from the engine125,325to the volute passages214,216. The available volume for exhaust flow may be relatively low because the first manifolds226,278,426,478may provide open flow paths while the second manifolds228,280,428,480are closed off. This may provide improved efficiency, for example, at relatively low engine speeds. However, when necessary, the available volume for exhaust gas flow may be selectively increased such that the first manifolds226,278,426,478and the second manifolds228,280,428,480cooperate to provide open flow paths. Accordingly, there is unlikely to be backpressure that would impede flow to the volute passages214,216.

As used herein, the term module refers to any hardware, software, firmware, electronic control component, processing logic, and/or processor device, individually or in any combination, including without limitation: application specific integrated circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group) and memory that executes one or more software or firmware programs, a combinational logic circuit, and/or other suitable components that provide the described functionality.