System and method for bypassing a gasoline particulate filter

Abstract

Device (200) comprising: a gasoline particulate filter (GPF, 244) arranged in an exhaust passage (202); a central bypass passage (218) having a first portion (220) upstream of the GPF (244) and a second portion (222) passing through a center of the GPF (244); a converging cone (210) forming a portion of the exhaust passage (202) and disposed upstream of and adjoining the first portion (220); one or more outer passages (230) coupled between the converging cone (210) and the GPF (244) and spaced from the central bypass passage (218); and a valve (224) disposed within the first portion (220).

Description

Area

[0001] This description generally relates to methods and systems for an exhaust aftertreatment system of a motor vehicle. General state of the art / Summary

[0002] Some internal combustion engines use a gasoline particulate filter (GPF) in an exhaust system to capture particulate matter flowing through the exhaust system and thereby meet emissions standards. GPFs can be constructed of porous ceramic or other porous materials. Regardless of the specific design, the purpose of the filter is to filter soot particles—where the soot particles consist of solid carbon, often with adsorbed hydrocarbons—from the exhaust gas passing through the filter and then retain the filtered soot particles within the filter until the filter is regenerated by the combustion of soot to form gaseous products. Soot is generated in a gasoline engine primarily in the first few minutes after a cold start. In addition to soot, the exhaust also carries non-combustible solid material called ash, which can also be captured by the GPF.However, because ash is non-combustible, it can remain in the filter throughout its useful life. Ash primarily comes from lubricating oil entering the combustion chamber or exhaust pipes. Other sources include corrosion from the exhaust manifold and deposits from the upstream catalyst. Ash is generated during all engine operating modes. When particulate matter (e.g., ash and soot) accumulates in a particulate filter (e.g., the GPF), exhaust backpressure can increase, which can adversely affect fuel economy. Although active regeneration of the GPF can remove stored soot, stored ash may remain within the filter after regeneration, and thus, the exhaust backpressure generated by the GPF may only be partially reduced. As such, ash can continue to contribute to exhaust backpressure on the engine, reducing engine speed, performance, and / or fuel economy.

[0003] Other attempts to address the buildup of particulate matter within a GPF include the use of a bypass system that bypasses the exhaust flow around the GPF. Specifically, the bypass system may include a bypass passage parallel to the GPF and a valve disposed within the bypass passage to control flow through the bypass passage. An exemplary approach is shown by Gonze et al. in US 2012 / 0 060 482 A1. Therein, Gonze discloses methods for regenerating a gasoline particulate filter (GPF) in a spark-ignition engine. Gonze also discloses a GPF bypass device for the GPF, wherein an annular channel extends through the central axis of the GPF. The portion of the annular channel closest to the upstream catalyst (e.g.where the exhaust first contacts the GPF and duct) is equipped with an operable valve to direct exhaust gases during various operating conditions of the vehicle.

[0004] Another exemplary approach is shown by Kono et al. in US 4,974,414 A and Arai et al. in US 5,105,619 A, which also disclose methods and systems for regenerating a particulate filter in a spark-ignition engine. Both documents utilize a bypass passage around a GPF, wherein the bypass passage includes a valve, and wherein a portion of the valve is disposed outside the bypass passage. The bypass passage runs parallel to and outside the GPF, adjacent to the GPF.

[0005] From DE 10 2010 034 104 A1, an exhaust gas aftertreatment device is known, comprising a single intake path for an exhaust gas inflow from an internal combustion engine; a coated substrate having a first substrate portion fluidly parallel to a second substrate portion; and “a flow modification device configured to selectively restrict a flow of the exhaust gas inflow exclusively to the first substrate portion, exclusively to the second substrate portion, and simultaneously to the first substrate portion and the second substrate portion in controllably variable percentages.

[0006] However, the inventors of the present invention have identified potential problems with such systems. For example, the valve located at the mouth of the annular passage (e.g., within the GPF enclosure, as shown in Gonze) complicates access to the valve for repair / replacement and traps heat within the system, posing a challenge to component durability. As another example, bypass passages located adjacent and parallel to the GPF enclosure increase the diameter and / or width of the system, thereby increasing the overall packaging space of the GPF system and emission control devices.

[0007] As an example, the problems described above can be addressed by a device comprising: a gasoline particulate filter (GPF) disposed in an exhaust passage; a central bypass passage having a first portion upstream of the GPF and a second portion passing through a center of the GPF; a converging cone forming a portion of the exhaust passage and disposed upstream of and connecting to the first portion; one or more outer passages coupled between the converging cone and the GPF and spaced from the central bypass passage; and a valve disposed within the first portion. In this way, the package size of an exhaust system including the GPF can be reduced, and the valve in the central bypass passage can be more easily accessible for repair and / or replacement.

[0008] The above advantages and other advantages and features of the present description will become more apparent from the following detailed description, which should be read alone or in conjunction with the accompanying drawings.

[0009] It is understood that the above Summary is provided to introduce, in simplified form, a selection of concepts that are further described in the Detailed Description. It is not intended to identify key or essential features of the claimed subject matter, the scope of which is defined solely by the claims that follow the Detailed Description. Furthermore, the claimed subject matter is not limited to implementations that resolve any disadvantages noted above or in any part of this disclosure. Short description of the drawings Fig. 1 is a block diagram of an engine system in a vehicle. Fig. 2A shows an exemplary emission control device including a gasoline particulate filter (GPF) and a GPF bypass passage with a bypass valve in a first position. Fig. 2B shows the exemplary emission control device having the GPF and the GPF bypass passage with a bypass valve in a second position. Fig. 3 is a cross-sectional view of the exemplary emission control device of Fig. 2B. Fig. 4 is a flowchart illustrating a method for adjusting a GPF bypass valve disposed in a bypass passage for a GPF in response to engine operating conditions. Fig. 5 shows a flowchart illustrating a method for performing a GPF regeneration event in an emissions control device having a GPF. Detailed description

[0010] The following description relates to systems and methods for an emissions control device including a gasoline particulate filter (GPF) in an engine system such as that described in Fig. 1 shown engine system. As in Fig. 1, the emissions control device may be disposed downstream of engine cylinders of an engine of the engine system in an exhaust passage of the engine system. The GPF filters particulate matter from the exhaust gases flowing through the exhaust passage before exiting the engine system. Although some of these particulates (e.g., soot) may be removed from the filter via regeneration events, other non-combustible particulates (such as ash) may remain within the GPF throughout the life of the filter, increasing a pressure drop across the GPF and subsequently increasing exhaust backpressure on the engine. Thus, the emissions control device may include a bypass passage that allows exhaust gases from the engine cylinders to bypass the GPF under certain engine operating conditions (e.g., such as when ash is allowed to flow through the exhaust passage or during conditions of reduced soot generation). Fig. 2A to 2B show an example of such an emission control device when the bypass passage is a central bypass passage extending through a center of the GPF. As in Fig. 2A to 2B, the central bypass passage includes a valve that is adjustable via a control unit of the engine system to selectively allow a different percentage of exhaust gases to pass through the GPF (via a plurality of peripheral passages positioned around the central bypass passage) or to bypass the GPF through the bypass passage. As shown in a cross-section of the emission control device of Fig. 2A to 2B, which in Fig. 3, the peripheral passages and the central bypass passage may be spaced apart from each other while still being positioned within an outer diameter (or width) of the emission control device as defined by a housing of the GPF and / or additional emission control devices (e.g., catalysts) of the emission control device. Fig. Figure 4 shows a flowchart illustrating a method for controlling the valve in response to a range of vehicle operating conditions. After a period of engine use, particulate matter may build up in the GPF, causing a pressure drop across the filter to increase. As a result, the control unit may initiate active regeneration of the GPF to burn soot from the filter, as shown in Fig. 5. As also shown in Fig. As shown in Figure 5, the controller may adjust a position of the valve during the regeneration event to maintain desired conditions for the regeneration event. Thus, adjusting the valve in the central bypass passage may reduce the amount of non-combustible particulate matter stored within the GPF, thereby reducing backpressure on the engine and increasing the longevity of the GPF. Additionally, the arrangement of the peripheral passages and the central bypass passage may allow the valve to be more easily serviced while also reducing the packaging space of the emission control device within the engine system.

[0011] Fig. 1 schematically illustrates a cylinder of a multi-cylinder engine 10 that may be included in a propulsion system of an automobile. The engine 10 may be controlled at least in part by a control system including the control unit 12 and by input from a vehicle operator 132 via an input device 130. In this example, the input device 130 includes an accelerator pedal and a pedal position sensor 134 to generate a proportional pedal position signal PP. A combustion chamber (i.e., a cylinder) 30 of the engine 10 may include combustion chamber walls 32 with a piston 36 positioned therein. In some embodiments, the surface of the piston 36 within the cylinder 30 may include a bowl. The piston 36 may be coupled to a camshaft 40 such that reciprocating motion of the piston is translated into rotational motion of the camshaft.The camshaft 40 may be coupled to at least one drive wheel of a vehicle via an intermediate transmission system. Furthermore, a starter motor may be coupled to the camshaft 40 via a flywheel to enable starting operation of the engine 10.

[0012] Combustion chamber 30 may receive intake air from an intake manifold 44 via intake passage 42 and may expel combustion gases via exhaust passage 48. Intake manifold 44 and exhaust passage 48 may selectively communicate with combustion chamber 30 via a respective intake valve 52 and exhaust valve 54. In some embodiments, combustion chamber 30 may include two or more intake valves and / or two or more exhaust valves.

[0013] The intake valve 52 may be controlled by the control unit 12 via an electric valve actuator (EVA) 51. Similarly, the exhaust valve 54 may be controlled by the control unit 12 via an EVA 53. Alternatively, the variable valve actuator may be electro-hydraulic or any other conceivable mechanism to enable valve actuation. During some conditions, the control unit 12 may vary the signals supplied to the actuators 51 and 53 to control the opening and closing of the respective intake and exhaust valves. The position of the intake valve 52 and exhaust valve 54 may be determined by valve position sensors 55 and 57, respectively.In alternative embodiments, one or more of the intake and exhaust valves may be actuated by one or more cams and may include one or more of cam profile shifting (CPS), variable cam timing (VCT), variable valve timing (VVT), and / or variable valve lift (VVL) systems to vary valve operation. For example, cylinder 30 may alternatively include an intake valve controlled via electric valve actuation and an exhaust valve controlled via cam actuation including CPS and / or VCT.

[0014] A fuel injector 66 is shown directly coupled to the combustion chamber 30 for injecting fuel directly therein proportional to the pulse width of the FPW signal received from the control unit 12. In this manner, the fuel injector 66 provides what is known as direct injection of fuel into the combustion chamber 30. The fuel injector may be mounted, for example, on the side of the combustion chamber or in the top of the combustion chamber. Fuel may be supplied to the fuel injector 66 from a fuel system (not shown) including a fuel tank, a fuel pump, and a fuel rail.

[0015] An ignition system 88 may provide an ignition spark to the combustion chamber 30 via a spark plug 92 in response to a pre-ignition signal SA from the control unit 12 under select operating modes. Although the spark ignition components are shown, in some examples, the combustion chamber 30 or one or more other combustion chambers of the engine 10 may be operated in a compression ignition mode with or without an ignition spark.

[0016] The intake passage 42 or intake manifold 44 may include a throttle 62 having a throttle plate 64. In this particular example, the position of the throttle plate 64, or a throttle opening, may be varied by the controller 12 via a signal provided to an electric motor or actuator included in the throttle 62, a configuration commonly referred to as electronic throttle control (ETC). In this manner, the throttle 62 may be operated to vary intake air supplied to the combustion chamber 30 among other engine cylinders. The position of the throttle plate 64 may be communicated to the controller 12 via a throttle position signal TP. The intake passage 42 may include a mass air flow sensor 120 and a manifold air pressure sensor 122 to provide respective signals MAF and MAP to the controller 12.

[0017] Further, in the disclosed embodiments, an exhaust gas recirculation (EGR) system 100 may direct a desired portion of the exhaust gas from the exhaust passage 48 to the intake manifold 44. In this example, a high-pressure (HP) EGR passage 140 is illustrated. The amount of EGR supplied to the intake manifold 44 may be varied by the control unit 12 via an HP EGR valve 142. Further, an EGR sensor 144 may be disposed within the HP EGR passage 140 and may provide an indication of one or more of pressure, temperature, and concentration of the exhaust gas. Alternatively, EGR flow may be controlled by a calculated value based on signals from the MAF (upstream), MAP (intake manifold), MAT (manifold gas temperature), and the cam speed sensor. Furthermore, the EGR flow can be controlled based on an exhaust O2 sensor and / or an intake oxygen sensor (intake manifold).Under certain conditions, the EGR system can be used to regulate the temperature of the air-fuel mixture within the combustion chamber and / or the temperature near the GPF 72. Although . Fig. 1 shows a high-pressure EGR system, a low-pressure EGR system may be used in addition or alternatively. In a low-pressure EGR system, the EGR may be routed from downstream of a turbocharger turbine to upstream of a turbocharger compressor, as in Fig. 1 shown.

[0018] As such, the engine 10 may further include a compression device, such as a turbocharger or supercharger, having at least one compressor 162 disposed along the intake manifold 44. For a turbocharger, the compressor 162 may be driven at least partially by a turbine 164 (e.g., via a shaft) disposed along the exhaust passage 48. For a supercharger, the compressor 162 may be driven at least partially by the engine 10 and / or an electric machine and may not include a turbine. Thus, the amount of compression applied to one or more cylinders of the engine via a turbocharger or supercharger may be varied by the controller 12.

[0019] Upstream of the turbine 164 and coupled between the exhaust passage 48 and a bypass passage 165 is a wastegate valve 163. Depending on the position of the wastegate valve, the amount of exhaust gas passing through the turbine 164 can be controlled. The position of the wastegate valve 163 can be controlled via a wastegate actuator (not shown, and which can be hydraulic, pneumatic, electrical, or mechanical) in response to a signal from the control unit 12. For example, the control unit 12 may wish to increase the speed and may achieve this by increasing the boost pressure. One way to increase the boost pressure is to increase the amount of power going to the turbine 164. For more power to the turbine 164, the control unit can signal the wastegate actuator to change the wastegate valve 163 to a first position, or a first position (e.g.fully closed) such that no exhaust gas can flow through the bypass passage 165 and all exhaust gas must pass through the turbine 164. Conversely, to reduce boost pressure, the controller 12 may signal the wastegate actuator to cause the wastegate valve 163 to assume or maintain a second position (e.g., fully open) to allow a percentage of the exhaust gas flowing from the exhaust passage 48 to flow past the wastegate valve 163 through the bypass passage 165, thereby bypassing the turbine 164 until the bypass passage 165 reconnects to the exhaust passage 48 downstream of the turbine 164. It is clear that the wastegate valve 163 can assume several intermediate positions (in response to the control unit 12 signaling the wastegate actuator to change the position of the wastegate valve 163) which lie between the first (e.g.fully closed) and second (e.g. fully open) positions so that variable amounts of exhaust gas can flow through the bypass passage 165, thereby bypassing the turbine 164.

[0020] An exhaust gas sensor 126 is shown coupled to the exhaust passage 48 upstream of an emissions control device (ECD) 70. The exhaust gas sensor 126 may be any suitable sensor to provide an indication of the exhaust air-fuel ratio, such as a linear oxygen sensor or UEGO (universal or wideband exhaust gas oxygen), a dual-state oxygen sensor or EGO, a HEGO (heated EGO), a NOx, HC, or CO sensor. Although the oxygen sensor 14 and temperature sensor 16 are shown in addition to the exhaust gas sensor 126 in Fig. 1, one or more of these sensors may be omitted and / or moved.

[0021] The emissions control device (ECD) 70 is shown disposed along the exhaust passage 48 downstream of the exhaust gas sensor 126. The ECD 70 includes a three-way catalyst (TWC) 71, a gasoline particulate filter (GPF) 72, and a pressure sensor 15. In some embodiments, the GPF 72 may include one or more catalyst materials in addition to components configured to filter exhaust gas. For example, the GPF 72 may be coated with a washcoat comprising one or more catalyst materials. Such a configuration may be used for embodiments in which the engine 10 is spark-ignited, for example. In some embodiments, the TWC 71 and the GPF 72 may be separate components comprising separate housings positioned away from each other (e.g., with the TWC upstream of the GPF, as in Fig. 1, Fig. 2A and Fig. 2B), with a valve between them (in Fig. 1 not shown) arranged at / in a GPF bypass passage arranged along a common axis. Details regarding exemplary ECDs are described below with reference to Fig. 2A and Fig. 2B. However, it is understood that the ECD 70 is provided as a non-limiting example, and that in other embodiments, the ECD may include other components in addition to or in place of the TWC 71 and / or the GPF 72, including, but not limited to, a lean NOx trap, an SCR catalyst, a diesel or gasoline particulate filter, an oxidation catalyst, or an alternative gas treatment device. For example, in some embodiments, an alternative catalyst or exhaust aftertreatment device may be positioned upstream of the GPF 72 instead of the TWC 71.

[0022] The control unit 12 is in Fig. 1 as a microcomputer comprising a microprocessor unit 102, input / output ports 104, an electronic storage medium (e.g., computer-readable) for executable programs and calibration values, shown in this particular example as read-only memory 106, a random access memory 108, a keep-alive memory 110, and a data bus.The control unit 12 may receive various signals from sensors coupled to the engine 10, in addition to the signals discussed above, including: induced mass air flow (MAF) measurement from the mass air flow sensor 120; engine coolant temperature (ECT) from the temperature sensor 112 coupled to a cooling sleeve 114; a profile ignition pickup (PIP) signal from a Hall sensor 118 (or other type) coupled to the camshaft 40; throttle position (TP) or throttle opening from a throttle position sensor; and a manifold absolute pressure signal, MAP, from the pressure sensor 122. An engine speed signal, RPM, may be generated by the control unit 12 from the PIP signal. The manifold pressure signal MAP from a manifold pressure sensor may be used to provide an indication of vacuum or pressure in the intake manifold.It should be noted that various combinations of the above sensors may be used, such as a MAF sensor without a MAP sensor, or vice versa. During stoichiometric operation, the MAP sensor may provide an indication of engine speed. Further, this sensor, along with the detected engine speed, may provide an estimate of the charge (including air) induced in the cylinder. In one example, sensor 118, which is also used as an engine speed sensor, may generate a predetermined number of evenly spaced pulses with each revolution of the camshaft. The control unit 12 receives signals from the various sensors from . Fig. 1 (e.g. pressure sensor 15, temperature sensor 112, pedal position sensor 134, etc.) and uses the various actuators (e.g. a valve actuator of a valve in a bypass passage of the GPF 72, as in Fig. 2A to 2B, throttle plate 64, spark plug 92, wastegate valve actuator 163, etc.) from Fig. 1 to adjust engine operation based on the received signals and information stored in a memory of the control unit. For example, adjusting a percentage of exhaust gases flowing through the GPF 72 (as described below with reference to Fig. 4), sending a signal from the control unit to an actuator of a valve (such as the one in Fig. 2A to 2B) within the ECD 70 to control valve positioning, thereby adjusting the percentage of exhaust gases flowing through the GPF 72.

[0023] The storage medium read-only memory 106 can be programmed with computer-readable data representing instructions executable by the microprocessor unit 102 to perform the methods described herein, as well as other variations that are anticipated but not specifically listed. As described above, Fig. 1 only one cylinder of a multi-cylinder engine, and each cylinder may similarly have its own set of intake / exhaust valves, fuel injectors, spark plugs, etc.

[0024] Fig. 2A to 2B and 3 show a portion of an exhaust passage in a vehicle exhaust system (such as the exhaust passage 48 in Fig. 1) that includes an emissions control device (ECD) 200. In some examples, the ECD 200 may include an ECD 70 of Fig. 1. Fig. 2A through 2B show a side view of the ECD 200, wherein the ECD 200 includes a central axis 248 passing through a center of the ECD 200. Fig. Figure 3 shows a section of the ECD 200 arranged such that a vertical axis 304 is perpendicular to the central axis 248, as in each of Fig. 2A and Fig. 2B. The section of Fig. 3 is downstream of a TWC casing 204 of Fig. 2A and Fig. 2B and upstream of a valve 224 of Fig. 2A to 2B, as shown by section AA of Fig. 2A to 2B.

[0025] As in Fig. 2A-2B, the ECD 200 includes a TWC 216, a GPF 244, and the operable valve 224 disposed along a central bypass passage 218 (located along the central axis 248 of an exhaust passage 202 and the GPF 244), and one or more peripheral passages 230. The central bypass passage 218 and the peripheral passages 230 connect a TWC housing 204 of the TWC 216 to a GPF housing 232 of the GPF 244.

[0026] The TWC 216 is disposed in the exhaust passage 202 upstream of the GPF 244. Further, the TWC 216 is disposed within the TWC housing 204, with the TWC housing 204 including a diverging cone 206 upstream of and coupled to a central portion 208 that is upstream of and coupled to a converging cone 210 of the TWC housing 204. The central portion 208 of the TWC housing 204 has a circumferential inner surface in face-sharing contact with the circumferential outer surface of the TWC 216, such that the central portion 208 is formed around and encloses the elements of the TWC. As used here, a diverging cone has angled sidewalls that angle outward from a narrower, upstream zone to a wider, downstream zone of the diverging cone.In contrast, a converging cone has angled sidewalls that angle inwardly from a wider, upstream zone to a narrower, downstream zone of the converging cone. Further downstream, the converging cone 210 forms a portion of the exhaust passage and includes a wider, first portion 212 (i.e., a first end) and a narrower, second portion 214 (i.e., a second end), the first end being coupled to an upstream portion of the exhaust passage, and the second end being directly coupled to an entrance into a first portion 220 of the central bypass passage 218. Stated another way, the converging cone 210 includes a wall that angles inwardly from the first portion 212 (i.e., first end) to the second portion 214 (i.e.,second end downstream of the first end) where it is coupled to the first portion 220 of the central bypass passage 218 (located downstream of the first end).

[0027] The central bypass passage 218 includes the first portion 220 located upstream of the GPF 244 and a second portion 222 passing through a center of the GPF 244 centered along the central axis 248. More specifically, the central bypass passage 218 includes the first portion 220 located upstream of the GPF 244 and the second portion 222 passing through a central aperture of the GPF 244 formed around the central axis 248. The first portion 220 of the central bypass passage 218 includes a valve 224 positioned therein. The valve 224 may be referred to herein as a bypass valve and is operable via a control unit (such as the one shown in Fig. 1) into a plurality of positions (e.g., a plurality of positions between fully open and fully closed, and including the fully open and fully closed positions). In this way, the valve 224 can be actively controlled based on engine operating conditions, as described below with reference to Fig. 4 to 5 discussed further.

[0028] The valve 224 includes a valve plate 226 and a valve actuator 228, wherein at least a portion of the valve actuator 228 is disposed outside an interior of the first portion 220 of the central bypass passage 218, and the valve plate 226 is positioned inside the interior of the first portion 220 of the central bypass passage 218. Furthermore, the portion of the valve actuator 228 disposed outside the interior of the first portion of the central bypass passage 218 is positioned within a space formed between an outer wall of the central bypass passage 218 and an outer wall of the one or more peripheral passages 230 (i.e., outer passages). The position of the valve 224 can be controlled by a control unit (such as the control unit 12 of Fig. 1) be adjusted with computer-readable instructions stored in a memory of the control unit to actuate such adjustment. The control unit may signal the actuator 228 of the valve 224 to actuate the valve to a first position (i.e., the fully closed position), as shown in Fig. 2A, so that the valve plate 226 of the valve 224 blocks exhaust gas from flowing through the central bypass passage 218. Alternatively, the control unit may signal (i.e., send a signal) to the actuator 228 of the valve 224 to actuate the valve to a second position (i.e., the fully open position), as shown in Fig. 2B, such that the valve plate 226 of the valve 224 is open to exhaust gas flowing through the central bypass passage 218. As an example, the actuator 228 may include a motor or hydraulic actuator that moves (e.g., rotates) the valve plate 226 of the valve 224 to various positions within the interior of the central bypass passage 218. Due to its external location, the actuator 228 may be accessible for maintenance, repair, and / or replacement. Further details regarding the position of the valve 224, exhaust flow, and engine operating conditions resulting in a change in the position of the valve 224 are found below.

[0029] With further reference to Fig. 2A and Fig. 2B, in addition to the converging cone 210 of the TWC housing 204 being coupled to the central bypass passage 218, the converging cone 210 of the TWC housing is also coupled to one or more peripheral passages 230 (i.e., outer passages). The peripheral passages 230 are coupled between the converging cone 210 and the GPF 244 and are spaced from the central bypass passage 218. More specifically, the plurality of peripheral passages 230 are positioned between the converging cone 210 and a diverging cone 234 of the GPF housing 232. For example, each of the peripheral passages 230 is coupled between the first portion 212 of the converging cone 210 and a second portion 238 of the diverging cone 234.The one or more peripheral passages 230 are circumferentially spaced about an outer side of the central bypass passage 218, but within an outer diameter of one of the exhaust passages upstream of the converging cone 210 or a central portion 240 of the GPF housing 232. In this manner, the peripheral passages 230 can be maintained within a packing space defined by the exhaust passage, the GPF housing 232, and / or the TWC housing 204. At least one of the one or more peripheral passages 230 is equipped with a pressure sensor 231 (similar to the one shown in FIG. Fig. 1), wherein a portion of the pressure sensor 231 may be disposed outside an interior of the peripheral passage 230, and a portion of the pressure sensor 231 may be positioned within the interior of the peripheral passage 230 to measure a pressure of the exhaust gas flowing through the peripheral passage 230. Thus, the pressure sensor may be in communication with the control unit. In alternative embodiments, the pressure sensor 231 may be coupled to one of the converging cone 210 or diverging cone 234 such that the pressure sensor is disposed upstream of the GPF 244. The peripheral passages 230 allow different percentages of exhaust gases to pass from the TWC housing 204 to the GPF housing 232 depending on the position of the valve 224, as discussed further below.

[0030] As stated above, the peripheral passages 230 are coupled to the downstream GPF housing 232. For example, an upstream, first end of the peripheral passages 230 is coupled to the converging cone 210, and a downstream, second end of the peripheral passages 230 is coupled to the diverging cone 234 of the GPF housing 232. The GPF housing 232 includes the diverging cone 234 upstream of and coupled to a central portion 240 of the GPF housing 232, which is upstream of and coupled to a second converging cone 242 of the GPF housing 232. The diverging cone 234, which forms a portion of the housing of the GPF, is disposed upstream of the GPF 244 and downstream of an entrance to the first portion 220 of the central bypass passage 218. The diverging cone 234 includes a narrower, first portion 236 (ieThe first end of the GPF 244 is formed by a first portion 238 (i.e., the first end) coupled to an outer wall of the first portion 220 of the central bypass passage 218, and a wider, second portion 238 (i.e., the second end) coupled to the central portion 240 of the GPF housing (i.e., GPF housing 232) surrounding the GPF 244. The central portion 240 of the GPF housing (i.e., GPF housing 232) is formed around and encloses the filter elements of the GPF 244 and is coupled between the diverging cone 234 and the second converging cone 242, the second converging cone being located downstream of the GPF 244. The GPF 244, disposed in the exhaust passage 202 and having the central axis 248, is circumferentially disposed around an outer periphery of the central bypass passage 218, specifically the second portion 222 of the central bypass passage 218.

[0031] Following the disclosure of the structural elements of ECD 200 in Fig. 2A and Fig. 2B, the path that an exhaust flow 246 may take in the ECD 200 depending on the position of the valve 224 can be further discussed. The position of the valve 224 may be changed or maintained depending on engine operating conditions to adjust the percentage of the exhaust flow 246 that flows through the peripheral passages 230 and through the GPF 244. Specifically, Fig. 2A the exhaust gas flow 246 through the ECD 200 when the valve 224 is in the first position (e.g., closed position), thereby blocking exhaust gases from flowing through the central bypass passage 218. Fig. 2B shows the exhaust flow 246 through the ECD 200 when the valve 224 is in the second position (e.g., open position), allowing exhaust gases to flow through the central bypass passage 218. As introduced above, the exhaust flow 246 through the ECD 200 may include exhaust gases flowing through the exhaust passage in which the ECD 200 is installed from one or more engine cylinders.

[0032] With reference to Fig. 2A, the exhaust flow 246 first enters the ECD 200 through the exhaust passage 202 and subsequently enters the diverging cone 206 of the TWC housing 204. The entire exhaust flow 246 then passes through the TWC 216 and into the converging cone 210. The angled, tapered shape of the converging cone 210 (as discussed above) directs exhaust gases to the first portion 220 of the central bypass passage 218. Because the valve 224 is in a fully closed (i.e., first) position, no exhaust flow can continue downstream in the first portion 220 of the central bypass passage 218 and is thus directed back to the upstream converging cone 210.The entire exhaust stream 246 is thus directed to pass through one or more peripheral passages 230 coupled to the wider portion of the converging cone 210 and ultimately downstream to the diverging cone 234 of the GPF housing 232. Alternatively, some of the exhaust stream 246 may initially pass through the peripheral passages 230 after exiting the TWC 216 without first being directed to the first portion 220 of the central bypass passage 218. The entire exhaust stream 246 then passes through the elements (e.g., filter elements) of the GPF 244 and into the downstream second converging cone 242 of the GPF housing 232. Thus, the entire exhaust stream 246 is filtered by the GPF 244 when the valve 224 is fully closed. The exhaust stream 246 may then continue through the most downstream portion of the ECD 200, the exhaust passage 202, where it then exits the ECD 200.Some examples of when valve 224 may be in a first position include one or more of a cold start condition including an engine temperature below a threshold temperature, an active GPF regeneration event, and vehicle acceleration above a threshold level (referring to FIG. Fig. 4 and Fig. 5 described in more detail).

[0033] With reference now to Fig. 2B, the exhaust stream 246 moves in the same initial steps as in Fig. 2A. The exhaust stream 246 first enters the ECD 200 through the exhaust passage 202 and subsequently enters the diverging cone 206 of the TWC housing 204. The entire exhaust stream 246 then passes through the TWC 216 and into the converging cone 210. The angled, converging inner surface of the converging cone 210 (discussed above) directs a larger percentage of the exhaust stream 246 into the first portion 220 of the central bypass passage 218 than into the peripheral passages 230, with the remaining percentage of the exhaust stream 246 passing through the one or more peripheral passages 230. Because the valve is in a second position (e.g., fully open), the exhaust flow 246 may continue downstream within the central bypass passage 218 to the second portion 222 of the central bypass passage 218.The second portion 222 of the central bypass passage bypasses the GPF (as discussed above), allowing the exhaust stream 246 to pass through the central portion 240 of the GPF housing 232 without passing through or contacting the internal elements of the GPF 244. Once the exhaust stream 246 exits the second portion 222 of the central bypass passage 218, it enters the diverging cone 234 of the GPF housing 232 and travels to the most downstream portion of the ECD 200, the exhaust passage 202, where it exits the device.Some examples of when valve 224 may be in a second position include one or more of a cold start condition, when the engine temperature is at or above a threshold temperature, or when the vehicle acceleration is not above the threshold level and the GPF active regeneration event is not occurring (discussed below with reference to FIG. Fig. 4 and Fig. 5). In this manner, when the valve 224 is in the second position, a larger, first portion of the exhaust gas passes through the central bypass passage 218, thereby bypassing the GPF, while a smaller, remaining second portion of the exhaust gas passes through the peripheral passages 230 and through the GPF 244 (e.g., to be filtered by the GPF).

[0034] Fig. 2A and Fig. 2B show first and second positions of the valve, respectively; however, the valve may be in a third (i.e., intermediate) position, where the third position is between the first and second positions. The controller may signal the actuator 228 to adjust the position of the valve plate 226 of the valve 224 to increase a degree of opening of the valve 224 to decrease the percentage of exhaust gas flowing through the peripheral passages 230 and subsequently through the GPF 244. Alternatively, the controller may signal the actuator 228 to adjust the position of the valve plate 226 of the valve 224 to decrease a degree of opening of the valve to increase the percentage of exhaust gas flowing through the peripheral passages 230 and subsequently through the GPF 244.

[0035] It is clear that Fig. 2A and Fig. 2B represent only one design for the ECD 200. Alternative embodiments may include different numbers of peripheral flow passages, may use different types of actuators, may use a catalyst or alternative gas treatment device other than a TWC, and / or may use more than one unitarily constructed GPF (i.e., multiple, smaller GPFs may be used while still maintaining an innermost central GPF bypass passage and an outermost surface sharing contact with the GPF housing). The Fig. 2A and Fig. The passages described in Figure 2B (i.e., exhaust passages 202, peripheral flow passage(s) 230, and central bypass passage 218) may have an annular shape or take on several geometric variations (such as square, hexagonal, etc.) as long as they retain the ability to allow exhaust gas to flow through their hollow bodies. Furthermore, the shapes of the TWC and GPF housings may have a central portion that is circular, square, rectangular, hexagonal, etc., and may be identical to or different from each other (i.e., the central portion of the GPF housing may take on a geometric configuration that is the same as or different from the geometric configuration of the central portion of the TWC housing).Further, the ECD system 200 may include one or more sensors disposed within the system responsible for monitoring the temperature or percentage of exhaust gas passing through at least one of the central bypass passage 218 and peripheral passage(s) 230. The sensors may transmit any collected data to the vehicle's control unit (such as control unit 12 shown in FIG. Fig. 1) which can respond by sending a signal to an actuator (such as the actuator 213 of Fig. 2A and Fig. 2B) signals a valve (such as valve 224 of Fig. 2A and Fig. 2B) to change the position in response to vehicle operating conditions.

[0036] With reference now to Fig. 3 shows a section of the ECD 200. As introduced above, the cross-section of the ECD 200 is arranged such that a vertical axis 304 is perpendicular to the central axis 248 which is formed in each of Fig. 2A and Fig. 2B. In addition, the cut is made along the Fig. 2B, downstream of the TWC housing 204 and upstream of the valve 224. In this embodiment, four peripheral (e.g., outer) passages 230 and a central bypass passage 218 are shown, allowing exhaust gas to flow from the TWC housing 204 to the GPF housing 232. As shown in Fig. 3, the four peripheral passages 230 surround an outer diameter of the central bypass passage 218. Within the central bypass passage 218, the valve 224 can be seen. As described above with reference to Fig. 2A-B, the valve 224 consists of the valve plate 226 and the actuator 228. The valve plate 226 is received within the diameter of the central bypass passage 218 and is operably controlled by the actuator 228. Further, each outer surface of each peripheral passage 230 is spaced from an outer surface of the central bypass passage 218 such that a space is formed around the central bypass passage 218. As shown in Fig. 3, the four peripheral passages 230 are circumferentially spaced around the central bypass passage 218. In alternative embodiments, the ECD 200 may include a number of peripheral flow passages other than four. For example, the ECD 200 may include one, two, three, or five peripheral flow passages circumferentially spaced around the central bypass passage 218, but spaced apart from the central bypass passage 218.

[0037] It is understood that the central bypass passage 218 and the peripheral passages 230 are housed within a space defined by an outer diameter 302 of a central portion 240 of the GPF housing. In other words, all of the peripheral passages 230 are disposed within the outer diameter 302 of the central portion 240 of the GPF housing in a radial direction (or a direction perpendicular to the central axis of the ECD 200). Housing all of the passages within a space defined by the outer diameter 302 of the central portion 240 of the GPF housing (but spacing the peripheral passages 230 from the central bypass passage 218) allows the ECD to be compact while still allowing access to the central valve 224.In other words, the vertical distance (as defined by the vertical axis 304) and the horizontal distance (as defined by a horizontal axis 306) from the central axis (at a center of the valve 224, such as the central axis 248 of . Fig. 2A and Fig. 2B) to each passage is smaller than the diameter of the central portion 240 of the GPF housing. It is clear that the central portions of the GPF housing and TWC housing determine the diameter of the housings, and thus the terms "diameter of the central portion of the GPF housing" and "diameter of the central portion of the TWC housing" may be interchangeable with "diameter of the GPF housing" or "GPF housing diameter" and "diameter of the TWC housing" or "TWC housing diameter", respectively. As in Fig. 2A to 2B, the TWC housing diameter is the same as the GPF housing diameter; however, in alternative embodiments, the TWC housing diameter may be different from the GPF housing diameter. In the embodiment where the diameters of the GPF housing and TWC housing are different, the peripheral passages 230 may fit within a space defined by the largest of the TWC housing diameter and the GPF housing diameter (such that the peripheral passages 230 do not extend outside the outer diameter of the GPF or TWC (whichever is largest). In another embodiment, the GPF housing and / or TWC housing may not have a circular cross-section (i.e., may not have an annular central portion), in which case the peripheral passages may fit within a space defined by a height and width (or cross-section) of a housing of the TWC and / or GPF.For example, the GPF and TWC housings may have a hexagonal central section with identical dimensions (while still maintaining a diverging cone upstream of the central section and a converging cone downstream of the central section), in which case all passages (i.e., peripheral flow passages and the central bypass passage) would be spaced within the cross-section of the hexagonal central section of the GPF and TWC housings.

[0038] The amount of exhaust flow (e.g., percentage of exhaust flow from the total exhaust flow passing through an exhaust passage and entering the ECD 200) passing through the peripheral passages 230 depends on the position of the valve 224. When the valve 224 is in the first position indicated above (not shown in Fig. 3), the central exhaust gas bypass passage 218 is closed, resulting in approximately 100% of the exhaust gases flowing through the peripheral passages 230 (as shown schematically in Fig. 2A). When the valve 224 is in the second position indicated above, as shown in Fig. 3 (also in Fig. 2B), the central bypass passage 218 is open, so that exhaust gases move down the central bypass passage 218 (and past the GPF), and a lower percentage of exhaust gases pass through the peripheral passages 230, the GPF housing 232, and through the GPF 244. The valve 224 may also assume several intermediate positions between fully closed to exhaust gases (i.e., first position) and fully open to exhaust gases (i.e., second position). Intermediate valve positions of valve 224 may affect the percentage of gases flowing through peripheral passages 230 and central bypass passage 218 such that when valve 224 moves from the second position to the first position (i.e., from closed to open), a larger percentage of exhaust gases passes through central bypass passage 218 and a lower percentage of exhaust gases passes through peripheral passages 230.

[0039] Although the central bypass passage 218, the peripheral passages 230, and the GPF housing 232 are all illustrated as having a ring shape, alternative embodiments may utilize multiple geometric configurations. For example, the passages may be square, rectangular, hexagonal, etc. In addition, alternative embodiments may require varying numbers of peripheral passages 230 (i.e., one or more peripheral flow passages). Although the valve 224 in Fig. 3 with an axis perpendicular to the vertical axis 304, alternative embodiments may have the axis of the valve 224 arranged at angles less than or greater than 90° to the vertical axis 304. Further, Fig. 1 to 3 illustrate example configurations with relative positioning of the various components. When shown as being in direct contact or directly coupled with one another, such elements may each be referred to as being in direct contact or directly coupled with one another, at least in one example. Similarly, elements shown as adjacent or juxtaposed may each be adjacent or proximate to one another, at least in one example. As an example, components that are in face-sharing contact with one another may be referred to as being in face-sharing contact. As another example, elements that are positioned spaced apart from one another with only a space and no other components between them may be referred to as such, at least in one example.

[0040] With reference to Fig. 4 shows a method for adjusting a valve positioned in a bypass passage located through a center of a GPF to vary a percentage of exhaust gas passing through the GPF. As introduced above, an emission control device (such as that shown in Fig. 2A to 2B and 3) an upstream aftertreatment device (such as the one shown in Fig. 2A to 2B) and a GPF (like the one shown in Fig. 2A to 2B and 3) and a central bypass passage (such as the one shown in Fig. 2A to 2B and 3) passing through a center of the GPF, thereby allowing exhaust gas to pass through the passage and not through pores (or filter elements) of the GPF. The central bypass passage has a valve disposed therein (such as the one shown in Fig. 2A to 2B and 3), upstream of a portion of the passageway passing through the center of the GPF. The valve is adjustable to multiple positions to adjust a percentage of exhaust gas flowing through the central bypass passageway and / or through the GPF. Instructions for performing method 400 and the remainder of the methods included herein may be provided by a control unit (such as the one shown in Fig. 1) on the basis of instructions stored in a memory of the control unit and in conjunction with signals received from sensors of the engine system, such as those described above with reference to Fig. 1. The control unit may use motor actuators of the motor system to adjust motor operation according to the methods described below. Furthermore, Fig. 4 and Fig. 5, which are described below, the valve in the central bypass passage of the GPF may be in a first position, a second position, or an intermediate position located between the two positions. In addition, in Fig. 4 and Fig. 5, which are described below, the valve in the central bypass passage of the GPF will be referred to simply as “valve”. The reader may assume that all valve references in Fig. 4 and Fig. 5 refer to the valve in the central bypass passage of the GPF (such as valve 224 of Fig. 2A, Fig. 2B, Fig. 3) unless otherwise noted. As used herein, when the valve is in a "first position," the valve may be referred to as "closed" (e.g., closed so that exhaust gases do not flow past the valve and through the central bypass passage), whereby exhaust gases cannot flow through the central bypass passage, and in response, all exhaust gases flow through peripheral flow passages surrounding the central bypass passage and connecting the upstream catalyst (e.g., TWC) to the GPF. Additionally, as used herein, when the valve is in a "second position," the valve may be referred to as "open," whereby exhaust gases can flow through the central bypass passage, and in response, a percentage of the exhaust gases flow through the central bypass passage while the remaining percentage of the exhaust gases flow through the peripheral flow passages.Furthermore, it is to be understood that any references to the valve being operated open or to a change in valve position (e.g., first, second, open, closed, intermediate, etc.) imply that the control unit uses an actuator of the valve (which may be at least partially located outside the central bypass passage) to move a position of the valve plate of the valve (the valve plate positioned across an interior of the central bypass passage) to the desired position and thus change the amount of exhaust flow passing through the central bypass passage.

[0041] Fig. 4 begins at 402, where engine operating conditions are estimated and / or measured. Determining and / or measuring engine operating conditions may include: processing incoming data from sensors inside and / or outside the ECD, determining whether the vehicle has just been started (i.e., cold start), whether the vehicle is under cruise control, whether the vehicle is accelerating / decelerating, etc. For example, the engine operating conditions may include engine speed and / or load, exhaust oxygen content, ambient temperature, engine temperatures, a pressure upstream of the GPF, a percentage of exhaust flowing through the GPF, a temperature of the EDC, an exhaust oxygen content of the EDC, etc.

[0042] At 404, the method includes determining whether the engine is operating under cold-start conditions. Cold-start conditions may include starting the engine when a temperature of the engine (and / or an ambient temperature) is below a threshold temperature. The threshold temperature may be based on a nominal operating temperature for the engine when engine fluids are heated to a threshold level. During the cold-start phase (e.g., when the engine temperature, or engine coolant temperature, is lower than the threshold temperature), the engine may generate soot because the controller uses a warm-up strategy to heat the catalyst in the exhaust passage (e.g., TWC) as quickly as possible. One aspect of this warm-up strategy may include late fuel injection, where the controller actuates the fuel injectors to delay the fuel injection timing into the engine cylinders.Other aspects of the warm-up strategy may include adjustments to ignition timing, idle, air-fuel ratio, and turbocharger operation. During cold start, these and possibly other aspects of engine operation are optimized for rapid catalyst warm-up (e.g., TWC) and are therefore not optimized for minimal particulate emissions. If the controller determines that the engine is operating under cold start conditions, the method proceeds to 406.

[0043] At 406, the method includes closing the valve of the central bypass passage of the GPF or maintaining the valve in the closed position (e.g., if it is already closed). As a result, all or most of the exhaust gases from the engine cylinders are directed through the peripheral flow passages and through the GPF. Thus, the GPF may filter the particulate soot material from the exhaust before the exhaust is expelled from the engine. In response to cold start conditions, the controller may signal an actuator of the valve in the central bypass passage to actuate the valve to the closed position so that the valve plate of the valve blocks exhaust gas from flowing through the bypass passage. Alternatively, if the central bypass passage valve is already fully closed, the controller may not send a signal to the valve actuator to maintain the valve in the closed position.In alternative embodiments, the valve may be actuated to move to a partially closed position, as opposed to fully closed, as long as the ECD continues to operate to remove a desired amount of soot from the exhaust as dictated by emissions standards (i.e., the valve may be 10% open to match engine operating conditions while still meeting emissions standards). After closing or maintaining a closed valve in the central bypass passage of the ECD, the method proceeds to 408.

[0044] At 408, the method includes the controller judging whether the engine warm-up period (i.e., cold start conditions or warm-up strategy) is complete. If the controller judges that the engine continues to operate under warm-up conditions, then the method proceeds to 410. As an example, the controller may determine that the engine warm-up period is not complete if the engine temperature continues to be below the threshold temperature. As another example, the controller may determine that the engine warm-up period is not complete if fuel injection continues to be late (e.g., delayed) relative to a threshold or default fuel injection time during engine-running conditions. As yet another example, the controller may determine that the warm-up period is not complete if a threshold period of time (e.g., for engine warm-up) has not elapsed.

[0045] At 410, the method includes maintaining the valve in the central bypass passage closed. Maintaining the valve closed may not require any action from the actuator controlling the central bypass passage valve. After 410 occurs, the method returns to 408. The method may alternate between 408 and 410 until the controller determines that engine warm-up is complete, at which point the method proceeds to 412.

[0046] At 412, the method includes opening the valve in the central bypass passage in response to the engine warm-up period being completed after the cold start. After completion of the warm-up conditions, and as long as no other engine operations are occurring that generate soot above a threshold level (e.g., where the threshold level is based on an emissions standard), the controller may signal the actuator of the valve in the central bypass passage of the GPF to actuate the valve to change position from closed to open. Changing the position of the valve from closed to open allows exhaust gases to pass through the central bypass passage, bypassing the GPF in the process. In one example, the method at 412 may include fully opening the valve in the central bypass passage. As another example, the method at 412 may include increasing the opening of the valve so that it is partially open.In some examples, the valve opening may increase as the engine warms up (e.g., as engine temperature rises or as fuel injection returns from the retarded state to the non-retarded base state). Once the valve has been successfully opened (either fully open or partially open depending on engine operating conditions), method 400 proceeds to 424 (as discussed further below).

[0047] If, referring again to 404, the controller has determined that the engine is not operating under cold start conditions, the method then proceeds to 414. At 414, the method includes determining whether active GPF regeneration conditions are met. Active GPF regeneration conditions may include a buildup of particulate matter (i.e., soot and / or ash) above a threshold in the GPF such that a pressure drop across the GPF is greater than a threshold level. As an example, the threshold level may be based on a level that results in increased backpressure on the engine cylinders, which causes a threshold percentage decrease in engine speed performance. Further, the controller may be programmed to detect a specific operating condition, such as steady highway driving, before determining that the regeneration conditions are met.If the controller determines at 414 that active GPF regeneration conditions are met, the method then proceeds to 416. At 416, the method includes closing the valve in the central bypass passage and regenerating the GPF. Closing of the valve occurs, as indicated above, via an actuator coupled to the valve in response to signals from the controller. The details of the regeneration of the GPF and valve operation during regeneration are discussed below with reference to FIG. Fig. 5 is discussed in more detail. After regeneration is complete, and if no other engine operating conditions are detected that require a change in valve position, method 400 ends.

[0048] If, referring again to 414, the active GPF regeneration conditions are not met, the method then proceeds to 418. At 418, the method includes determining whether the vehicle is accelerating. Acceleration may be detected based on an increase in throttle opening, an increased fuel injection rate, and / or an increase in pedal position above a threshold. Severe acceleration (e.g., a tip-in or a pedal position increase above a threshold) may result in an increase in engine soot emissions. Thus, in response to engine acceleration (or acceleration above a threshold), the controller may actuate the valve to fully close or partially close to a desired degree (via sending a signal to the actuator coupled to the valve) if the valve is not already closed.An acceleration threshold may be used to determine when soot is generated to a level that causes the controller to initiate a valve position change to meet emissions standards. If the vehicle accelerates, or accelerates above a predetermined threshold, the method then proceeds to 420.

[0049] At 420, the method includes closing (or partially closing) the valve in the central bypass passage. As discussed at 418, in response to vehicle acceleration, or acceleration above a predetermined threshold known to cause soot above a threshold level, the controller may signal the valve actuator to change the valve position to a fully closed or partially closed position (e.g., the controller may decrease the degree of opening of the valve).Determining whether to partially or fully close the valve can depend on a number of operating conditions, such as determining how closed the valve needs to be to reduce soot in the exhaust by a threshold amount, a pressure in the ECU, percentages of exhaust gas moving through the central bypass passage and the peripheral flow passages, a temperature of the exhaust gas, an air-fuel ratio, etc. If the actuator fully closes the valve (i.e. moves the valve to the first position), then all exhaust gases pass through the peripheral flow passages (like those shown in . Fig. 2A through 3), downstream of the GPF, where the increased soot emissions due to acceleration can be better captured in the filter. When the actuator partially closes the valve (i.e., an intermediate position between the first and second positions), an increased percentage of the exhaust gases then passes through the peripheral flow passages, while the remaining percentage continues to flow through the now partially blocked central bypass passage. After closing, or partially closing, the valve controlling access to the central bypass passage, method 400 proceeds to 424 (as further discussed below).It will be appreciated that in an alternative embodiment, the soot generated by increased acceleration (or acceleration above a predetermined threshold) may be addressed through engine calibration, eliminating the need for the controller to close the valve to meet soot thresholds. In such an alternative embodiment, the method would not proceed to 420, but instead proceed to 422.

[0050] Referring again to 418, if the vehicle is not accelerating, or is not accelerating at or above a predetermined threshold to trigger valve closure, as described above, the method then proceeds to 422. At 422, the method includes maintaining the open (or partially open) position of the valve in the central bypass passage. Maintaining the open valve (i.e., in the second position) may not require a signal from the controller to the valve actuator. It will be appreciated that other operating conditions may occur simultaneously to require the valve to be partially open rather than fully open, yet no acceleration is detected to cause valve closure at 418 above.Furthermore, some operating conditions may occur simultaneously that cause the control unit to fully close the valve position, even though no acceleration is detected to cause the valve to close in 418 above. For example, in 422, the control unit may detect a pressure signal that triggers the control unit to regenerate the GPF. Under these conditions, the control unit may determine that regeneration is more essential to engine operation than holding an open valve, and in response, the control unit may signal the actuator to close the valve, so that regeneration can occur, even though no acceleration is detected to cause the valve to close in 418 above. It is clear that, although schematically represented as a strictly sequential process, the control unit may simultaneously track all vehicle operations (e.g.,Determine cold start conditions, regeneration conditions, acceleration conditions, etc.) and continuously prioritize the conditions to determine the optimal valve position.

[0051] At 424, the method includes adjusting engine operation based on a change in pressure across the GPF due to adjustment of the position of the valve. For example, after adjusting the valve during the methods described above, the controller may determine the pressure across the GPF by using a first pressure reading within the ECD system, upstream of the GPF but downstream of the TWC, and a second pressure downstream of the GPF. In one example, the second pressure reading may be atmospheric pressure. Thus, determining the pressure drop across the GPF may include comparing the first pressure reading to the second pressure reading and determining whether the pressure drop affects engine speed performance.As another example, the control unit may determine the pressure upstream of the GPF and use that pressure to estimate backpressure on the engine and whether the engine speed is reduced above a threshold level due to the backpressure. For example, if the valve is in the first position (closed for exhaust gases bypassing the GPF, such as the one shown in . Fig. 2A), any exhaust gases entering the ECD pass through the peripheral flow passages and to the downstream GPF. When this occurs, the pressure drop across the GPF places an additional load on the engine, which may reduce engine speed performance. The pressure drop may reduce speed performance enough that the controller may take steps to compensate by increasing engine speed performance. As such, the method at 424 may include adjusting throttle opening, spark timing, or turbocharger boost pressure (in a turbocharged engine) to increase engine speed performance so that the effect of GPF backpressure is not noticeable to the driver. For example, as the pressure drop across the GPF (or the pressure upstream of the GPF) increases, the controller may increase throttle opening to increase speed.The amount of pressure drop may also depend on the amount of particulate matter accumulated in the GPF and / or the percentage of gases flowing through the GPF. For example, the valve may be fully open (i.e., second position) or partially open (i.e., between the first and second positions), allowing some exhaust gas to bypass the GPF. However, due to a large amount of particulate matter in the GPF, the pressure drop may be significant enough for the controller to adjust the engine conditions based on a change in pressure across the GPF. After adjusting the engine conditions based on a change in pressure across the GPF, method 400 ends.

[0052] In this way, a vehicle control unit can determine during which engine operating conditions increased soot generation is likely to occur and, in response to those operating conditions, signal an actuator of a valve in a central bypass passage of a GPF to adjust the valve accordingly. A closed valve blocks exhaust access to the central bypass passage, thereby directing all exhaust gas to move through the peripheral flow passages and through pores of the GPF. Comparatively, an open (or partially open) valve allows a portion of the exhaust gases to move down the central bypass passage and through a center of the GPF without flowing through the pores of the GPF, thereby reducing the amount of exhaust gas moving through the pores of the GPF.The control unit may estimate and / or measure a plurality of engine operating conditions simultaneously to determine a desired valve position of the valve, which may include the first position, the second position, or an intermediate position between the first and second positions, as described above.

[0053] With reference to Fig. 5, a method 500 is shown for performing a GPF regeneration event in an emissions control device that includes a GPF (such as the ECD 200 and GPF 244 shown in Fig. 2A to 2B and 3). It should be noted that the method 500 is a continuation of 416 in Fig. 4 is.

[0054] Method 500 begins at 502 by closing or partially closing the valve in the central bypass passage in response to the controller determining that the active GPF regeneration conditions are met, as described above with reference to 414 of Fig. 4. The method may include, at 502, determining, based on engine operating conditions, whether to partially close or fully close the valve. For example, fully closing the valve (i.e., the first position) may cause all heated exhaust gases to pass through pores of the GPF rather than through the central bypass passage in which the valve is installed. As a result, the temperature of the GPF may increase, and more soot stored within the GPF may be burned off by the filter during the regeneration event. In comparison, partially closing the valve (i.e., a position between the first and second positions) may cause fewer heated exhaust gases to pass through the pores of the GPF (than if the valve were fully closed), and thus the temperature of the GPF may not increase as much as if the valve were fully closed.As a result, the controller may control a temperature of the GPF during the regeneration event based on a position of the valve. There may be a threshold temperature or a temperature range for maintaining the GPF temperature during regeneration. For example, during regeneration, the controller may adjust the valve to maintain the GPF above a lower threshold temperature (e.g., below which soot cannot be removed from the filter) and below an upper threshold temperature (e.g., above which GPF degradation may occur). Furthermore, by only partially closing the valve, engine power loss (e.g., due to increased backpressure from exhaust gas flowing through the GPF) may be reduced.Once the controller has determined whether the valve should be fully or partially closed (and to what percentage of open or closed it should be moved), signaled the valve actuator, and adjusted the valve position accordingly, the method proceeds to 504.

[0055] At 504, the method includes determining whether the GPF is at a regeneration temperature. The GPF temperature may be determined based on the output of an exhaust gas temperature sensor positioned proximal to the GPF (such as the one shown in Fig. 1). The regeneration temperature may be a filter regeneration light-off temperature at which, given sufficient excess oxygen, particulate matter accumulated in the GPF may be oxidized. The temperature for regeneration may be a threshold or a range of values. If it is determined that the GPF is not at the regeneration temperature (e.g., below), the method then proceeds to 506. In 506, the method includes increasing the exhaust temperature in an effort to bring the GPF to the regeneration temperature. The exhaust temperature may also be controlled to achieve a desired oxidation rate of the particulate matter. Increasing the exhaust temperature causes the temperature of the GPF to also increase. Increasing the exhaust temperature in 506 may include one or more of retarding the spark timing, increasing the throttle opening (e.g., opening the throttle 62 from Fig. 1), an increase in engine speed, an increase in engine load, etc. Method 500 continues to cycle between 506 and 504 until the controller determines (at 504) that the GPF is at temperatures suitable for regeneration. If it is determined that the GPF is at (e.g., greater than or equal to) the regeneration temperature, method 500 proceeds to 508.

[0056] At 508, the method includes initiating active regeneration of the GPF. Initiating active GPF regeneration may include initiating deceleration fuel cut-off (DFSO) to provide oxygen for the oxidation of particulate matter (e.g., soot). In some examples, DFSO may only be initiated under select conditions, for example, DFSO may be initiated when engine speed and / or load are below respective thresholds, and / or when other inputs (e.g., throttle pedal position) do not indicate an imminent driver tip-in or rpm request. By initiating DFSO, sufficient levels of excess oxygen may be supplied to the GPF, which, in combination with sufficient temperatures, facilitates the oxidation of accumulated particulate matter and at least partial regeneration of the GPF.Thus, the GPF may be actively regenerated using excess oxygen obtained from the engine. Other approaches, alternative to or in addition to DFSO, may be used to increase excess oxygen in the GPF. For example, one or more of throttle opening, air-fuel ratio (e.g., leaning), and variable cam timing may be adjusted to increase the supply of excess oxygen. Once the controller initiates active regeneration, the method proceeds to 510.

[0057] At 510, the method includes adjusting the valve in the central bypass passage and a combustion air-fuel (A / F) ratio of the engine to maintain the GPF at the regeneration temperature. During regeneration, soot oxidation (i.e., soot combustion) is exothermic. If uncontrolled, regeneration may increase the temperature in the ECD sufficiently to damage the GPF. The reaction may be controlled using valve timing and / or air-fuel ratio control.For example, lower exhaust flow through the GPF with a higher air-fuel ratio can create higher temperatures in the GPF because the high oxygen content promotes rapid oxidation, and there is little exhaust gas flowing through the GPF to dissipate heat (due to an open or partially open valve directing a percentage of the exhaust gases through the central bypass passage, leaving a smaller percentage of the exhaust gases to flow through the GPF). In comparison, higher exhaust flow through the GPF (which occurs when the valve in the central bypass passage is fully closed or partially closed, preventing all or most of the exhaust gas from passing through the central bypass passage, respectively) with a low air-fuel ratio can cool the GPF because the exhaust gas contains little oxygen, and the high exhaust flow through the GPF can more quickly dissipate any heat generated.Thus, the controller may adjust the valve position (via sending a signal to the actuator coupled to the valve plate) and adjust the combustion air-fuel ratio (via sending a signal to one or more fuel injectors and / or the throttle valve) to increase or decrease heat within the ECD system so that temperatures do not fall below those consistent with active regeneration and do not rise above those that would degrade the GPF (or any other component of the ECD system). For example, at 510, the method may include increasing the air-fuel ratio combusted in the engine cylinders while increasing an opening of the valve in the central bypass passage to increase the temperature of the GPF when the regeneration temperature is below a threshold.As another example, the method at 510 may include decreasing the air-to-fuel ratio combusted in the engine cylinders while decreasing a valve opening in the central bypass passage to lower the GPF temperature when the regeneration temperature reaches a threshold that reduces component durability (e.g., a temperature that may degrade the GPF). In another embodiment, the method at 510 may additionally or alternatively include enriching the exhaust gas by increasing a fuel injection amount to lower the GPF temperature, since enriched exhaust gas tends to be cooler than lean exhaust gas.In this way, the method in 510 may include adjusting both the valve in the central bypass passage and the combustion air-fuel ratio to maintain the GPF temperature within a desired regeneration temperature range during the regeneration event.

[0058] At 512, the method includes determining whether regeneration is complete. The determination of whether regeneration is complete may be based on one or more of the temperature of the GPF, indicating that an exothermic reaction (i.e., regeneration) is no longer occurring (e.g., the temperature drops below a threshold), or a pressure drop across the GPF. For example, after combustion of much of the soot in the GPF during the regeneration process, exhaust gas entering the GPF will encounter less resistance passing through the GPF, and the pressure drop will be reduced (compared to before the regeneration event). In this example, the controller may determine that regeneration is complete when the pressure drop across the GPF has reduced below a threshold level. As another example, the threshold level may be a smaller level than the pressure drop across the GPF prior to initiating regeneration.As yet another example, the threshold level may be a set level that indicates that a certain percentage of particulate matter (e.g., soot) has been removed from the GPF.

[0059] Thus, there may be a threshold pressure drop indicating that regeneration is complete. If regeneration is not complete, the method continues to 514. At 514, the method includes continuing active regeneration. For example, regeneration may be continued by adjusting one or more of the valve in the central bypass passage, the combustion air-fuel ratio, the throttle, and / or the engine fueling to maintain the regeneration temperature range and continue to provide oxygen for regeneration, as described above at 508 and 510. Until the controller determines at 512 that regeneration is complete, the methodology will cycle between 512 and 514. Once the controller determines at 512 that regeneration is complete, the method continues to 516.

[0060] At 516, the method includes the controller returning the engine actuators to their requested state and reopening or increasing the opening of the central bypass valve. The requested state of the vehicle actuators may be determined by the driver (e.g., driver-initiated acceleration / deceleration), driving conditions (e.g., wet roads may cause a vehicle to engage four-wheel drive), and engine operating conditions (e.g., acceleration, cold start, regeneration, etc.). In the event that no other engine operating conditions require a closed valve (such as acceleration or cold start conditions), the controller may then signal the valve actuator to adjust the valve from a fully or partially closed valve position to a partially or fully open valve position. After adjusting the valve position in response to completed regeneration, method 500 ends.The control unit can further monitor engine operating conditions and provide additional valve position adjustments via an actuator, as shown in . Fig. 4 for the method 400, during the duration of vehicle operation.

[0061] In this way, an emission control device with a GPF bypass can be designed such that the ECD (such as the one in Fig. 2A and Fig. 2B) occupies no more space than an exhaust system accommodating only a TWC and a GPF (i.e., an exhaust system without a GPF bypass). The spacing between peripheral flow passages and a central bypass passage of the ECD allows for cooling of the exhaust gases, which reduces the heat of the ECD system and can extend the life of components within the system (since exposure to hot exhaust gases without a means of cooling can pose challenges to component durability). With at least a portion of the valve (e.g., a portion of the valve actuator) positioned outside the central bypass passage, in conjunction with the spacing surrounding the perimeter of the central bypass passage, the valve and / or valve actuator is more easily accessible, increasing the ease of servicing or replacing the valve.Furthermore, the shape of the converging cone section of the TWC housing (such as that shown in . Fig. 2A) that a greater amount of exhaust gases is directed to the central bypass passage when the valve is open or partially open than if the TWC housing had a straight design that was not angled to the central bypass passage.

[0062] The technical effect of providing a converging cone upstream of the first portion of the central bypass passage is to direct a greater percentage of the exhaust gases to the central bypass passage, thereby allowing a greater percentage of the exhaust gases to bypass the GPF and reducing the amount of incombustible particulate matter trapped within the pores of the GPF when the valve is in a second (e.g., open) position. The technical effect of spacing one or more outer (e.g., peripheral) passages disposed between the converging cone and the GPF away from the central bypass passage, in addition to positioning at least a portion of the valve actuator of the valve outside the central bypass passage, is to make the valve more easily accessible for repairs and maintenance.

[0063] As one embodiment, an apparatus for an engine emission control device comprises: a gasoline particulate filter (GPF) disposed in an exhaust passage; a central bypass passage having a first portion upstream of the GPF and a second portion passing through a center of the GPF; a converging cone forming a portion of the exhaust passage and disposed upstream of and connecting to the first portion; one or more outer passages coupled between the converging cone and the GPF and disposed at a distance from the central bypass passage; and a valve disposed within the first portion.In a first example of the device, the valve comprises a valve plate and a valve actuator, wherein at least a portion of the valve actuator is disposed outside an interior of the first portion of the central bypass passage, and the valve plate is positioned within the interior of the first portion of the central bypass passage. A second example of the device optionally includes the first example and further includes, wherein at least the portion of the valve actuator disposed outside the interior of the first portion of the central bypass passage is positioned within a space formed between an outer wall of the central bypass passage and an outer wall of the one or more outer passages.A third example of the device optionally includes one or more of the first and second examples, and further comprises wherein the converging cone has a wider first end and a narrower second end, the first end coupled to an upstream portion of the exhaust passage, and the second end directly coupled to an entrance to the first portion of the central bypass passage. A fourth example of the device optionally includes one or more of the first to third examples, and further comprises wherein the converging cone has a wall angled inwardly from the first end to the second end of the converging cone.A fifth example of the apparatus optionally includes one or more of the first to fourth examples and further comprises, further comprising a diverging cone forming a portion of a housing of the GPF and disposed upstream of the GPF and downstream of the first portion of the central bypass passage, the diverging cone having a narrower first end coupled to an outer wall of the first portion of the central bypass passage and a wider second end coupled to a central portion of the housing of the GPF surrounding the GPF. A sixth example of the apparatus optionally includes one or more of the first to fifth examples and further comprises, wherein each of the one or more outer passages is coupled between the first end of the converging cone and the second end of the diverging cone.A seventh example of the device optionally comprises one or more of the first to sixth examples and further comprises wherein the one or more outer passages comprise or comprise a plurality of outer passages circumferentially spaced about an exterior of the central passage but within an outer diameter of one of the exhaust passage upstream of the converging cone or the central portion of the housing of the GPF.An eighth example of the apparatus optionally includes one or more of the first to seventh examples, and further comprises wherein the central portion of the housing of the GPF is formed around and encloses filter elements of the GPF, and further comprises a second converging cone positioned at a downstream end of the GPF, the central portion of the GPF housing being coupled between the diverging cone and the second converging cone. A ninth example of the apparatus optionally includes one or more of the first to eighth examples, and further comprises wherein the GPF has a central axis, and wherein the central bypass passage is centered along the central axis, and wherein the GPF is circumferentially formed around an outer periphery of the central bypass passage.

[0064] In another example, a method for an engine emission control device comprises: during a first condition, adjusting a valve disposed in a central bypass passage upstream of a gasoline particulate filter (GPF) of an exhaust passage, the central bypass passage passing through a center of the GPF, to a first position to allow exhaust gas to flow from a converging cone forming a portion of the exhaust passage upstream of the central bypass passage and only through peripheral passages surrounding the central bypass passage and connecting a housing of the GPF to the converging cone; and during a second condition, adjusting the valve to a second position to allow at least a portion of the exhaust gas from the converging cone to flow through the central bypass passage.In the first example of the method, the method further comprises, after adjusting the valve, adjusting engine operation in response to a pressure drop across the GPF. A second example of the method optionally includes the first example and further comprises, wherein adjusting engine operation comprises adjusting one or more of a turbocharger boost pressure, spark timing, and throttle, and wherein the pressure drop is based on a pressure measured upstream of the GPF in the exhaust passage.A third example of the method optionally includes one or more of the first and second examples and further comprises wherein setting the valve to the first position to flow exhaust gas out of the converging cone and only through the peripheral passages comprises: flowing exhaust gas from the converging cone to an entrance of the peripheral passages coupled to a wider portion of the converging cone, flowing exhaust gas through the peripheral passages, flowing exhaust gas into a diverging cone forming an entrance to the GPF within a housing of the GPF, and flowing exhaust gas through filter elements of the GPF.A fourth example of the method optionally includes one or more of the first to third examples and further comprises, wherein setting the valve to the second position comprises: flowing exhaust from a wider portion of the converging cone to a narrower portion of the converging cone directly coupled to an inlet into the central bypass passage to direct exhaust into the central bypass passage following a converging inner surface of the converging cone, and flowing exhaust from the central bypass passage to a portion of the exhaust passage downstream of the GPF.A fifth example of the method optionally includes one or more of the first through fourth examples, and further includes wherein the first condition comprises one or more of a cold start condition having an engine temperature below a threshold temperature, a GPF active regeneration event, and vehicle acceleration above a threshold level. A sixth example of the method optionally includes one or more of the first through fifth examples, and further includes wherein the second condition comprises one or more of, after the cold start condition: when the engine temperature is at or above the threshold temperature, or when the vehicle acceleration is not above the threshold level and the GPF active regeneration event does not occur.A seventh example of the method optionally includes one or more of the first to sixth examples and further includes wherein the first position is a fully closed position and the second position is a fully open position, and further comprising: setting the valve to a third position, the third position being between the first position and the second position, during a third condition, the third condition comprising: during the active regeneration event of the GPF, and when the third position is based on a temperature of the GPF and a desired regeneration temperature of the GPF.

[0065] In another embodiment, a system for an emission control device comprises: a gasoline particulate filter (GPF) disposed in an exhaust passage and having a central axis; a three-way catalyst disposed in the exhaust passage upstream of the GPF; a central bypass passage having a first portion disposed upstream of the GPF and a second portion passing through a central aperture of the GPF formed around the central axis; a converging cone forming a downstream portion of a housing of the three-way catalyst and connecting to the first portion of the central bypass passage; a diverging cone forming an upstream portion of a housing of the GPF and disposed downstream of an entrance to the first portion of the central bypass passage; a plurality of peripheral passages,positioned between the converging and diverging cones and positioned at a distance from the central passage; a valve disposed within the first portion of the central bypass passage; and a control unit with computer-readable instructions for: adjusting a position of the valve to adjust a percentage of exhaust gas flowing through the outer passages and through the GPF, and adjusting engine operation in response to adjusting the position of the valve and based on a pressure upstream of the GPF. In a first example of the system, wherein the valve comprises a valve plate disposed within the first portion of the central bypass passage and a valve actuator, wherein at least a portion of the valve actuator is external to the first portion of the central bypass passage,and wherein adjusting the position of the valve comprises: increasing a degree of opening of the valve to decrease the percentage of exhaust gas flowing through the outer passages through the GPF, and decreasing the degree of opening of the valve to increase the percentage of exhaust gas flowing through the outer passages and through the GPF.,

[0066] It should be noted that the exemplary control and estimation routines contained herein may be used with various engine and / or vehicle system designs. The control methods and routines disclosed herein may be stored as executable instructions in non-transitory memory and may be performed by the control system, including the control unit in combination with the various sensors, actuators, and other engine hardware. The specific routines described herein may represent one or more of any number of processing strategies, such as event-driven, interrupt-driven, multitasking, multithreading, and the like. As such, various illustrated actions, operations, and / or functions may be performed in parallel, or in some cases omitted, from the illustrated sequence.Similarly, the order of processing is not required to achieve the features and advantages of the exemplary embodiments described herein, but is provided for ease of illustration and description. One or more of the illustrated actions, operations, and / or functions may be performed depending on the particular strategy employed. Further, the described actions, operations, and / or functions may graphically represent code to be programmed into a non-transitory memory of the computer-readable storage medium in the engine control system, wherein the described actions are performed by executing the instructions in a system including the various engine hardware components in combination with the electronic control unit.

[0067] It is understood that the configurations and routines disclosed herein are exemplary in nature, and that these specific embodiments are not to be considered in a limiting sense, as numerous variations are possible. For example, the above technology may be applied to V-6, I-4, I-6, V-12, horizontally opposed four engines, and other engine types. The subject matter of the present disclosure includes all novel and non-obvious combinations and subcombinations of the various systems and configurations and other features, functions, and / or characteristics disclosed herein.

[0068] The following claims particularly point out certain combinations and subcombinations that are considered novel and non-obvious. These claims may refer to "a" element or "a first" element, or the equivalent thereof. Such claims are to be understood as encompassing the inclusion of one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and subcombinations of the disclosed features, functions, elements, and / or properties may be claimed by amending the present claims or by presenting new claims in this or a related application. Such claims, whether broader, narrower, equal, or different in scope from the original claims, are also considered to be encompassed within the subject matter of the present disclosure.

Claims

[1] Device (200) comprising: a gasoline particulate filter (GPF, 244) arranged in an exhaust passage (202); a central bypass passage (218) having a first portion (220) upstream of the GPF (244) and a second portion (222) passing through a center of the GPF (244); a converging cone (210) forming a portion of the exhaust passage (202) and disposed upstream of and adjoining the first portion (220); one or more outer passages (230) coupled between the converging cone (210) and the GPF (244) and spaced from the central bypass passage (218); and a valve (224) disposed within the first portion (220). [2] The device (200) of claim 1, wherein the valve (224) comprises a valve plate (226) and a valve actuator (228), wherein at least a portion of the valve actuator (228) is disposed outside an interior of the first portion (220) of the central bypass passage (218), and the valve plate (226) is positioned within the interior of the first portion (220) of the central bypass passage (218). [3] The device (200) of claim 2, wherein at least the portion of the valve actuator (228) disposed outside the interior of the first portion (200) of the central bypass passage (218) is positioned within a space formed between an outer wall of the central bypass passage (218) and an outer wall of the one or more outer passages (230). [4] The device (200) of claim 1, wherein the converging cone (210) has a wider first end and a narrower second end, the first end coupled to an upstream portion (208) of the exhaust passage (202), and the second end directly coupled to an inlet to the first portion (220) of the central bypass passage (218). [5] The device (200) of claim 4, wherein the converging cone (210) has a wall that is angled inwardly from the first end to the second end of the converging cone (210). [6] The apparatus (200) of claim 4, further comprising a diverging cone (234) forming a portion of a housing (232) of the GPF (244) and disposed upstream of the GPF (244) and downstream of the first portion (220) of the central bypass passage (218), the diverging cone (234) having a narrower first end coupled to an outer wall of the first portion (220) of the central bypass passage (218) and a wider second end coupled to a central portion (240) of the housing (232) of the GPF (244) surrounding the GPF (244). [7] The device (200) of claim 6, wherein each of the one or more outer passages (230) is coupled between the first end of the converging cone (210) and the second end of the diverging cone (234). [8] The device (200) of claim 6, wherein the one or more outer passages (230) comprise or comprise a plurality of outer passages circumferentially spaced about an exterior of the central passage (218) but within an outer diameter of one of the exhaust passage (202) upstream of the converging cone (210) or the central portion (240) of the housing (232) of the GPF (244). [9] The apparatus (200) of claim 6, wherein the central portion (240) of the housing (232) of the GPF (244) is formed around and encloses filter elements of the GPF (244), and further comprises a second converging cone (242) positioned at a downstream end of the GPF (244), the central portion (240) of the GPF housing (232) being coupled between the diverging cone (234) and the second converging cone (242). [10] The device (200) of claim 1, wherein the GPF (244) has a central axis (248), and wherein the central bypass passage (218) is centered along the central axis (248), and wherein the GPF (244) is formed circumferentially around an outer periphery of the central bypass passage (218). [11] A method comprising: during a first condition determined by a control unit (12), adjusting, with the control unit (12), a valve (224) disposed in a central bypass passage (218) upstream of a gasoline particulate filter (GPF, 244) of an exhaust passage (202), the central bypass passage (218) passing through a center of the GPF (244), to a first position to allow exhaust gas to flow from a converging cone (210) forming a portion of the exhaust passage (202) upstream of the central bypass passage (218) and only through peripheral passages (230) surrounding the central bypass passage (218) and connecting a housing (232) of the GPF (244) to the converging cone (210); and during a second condition determined by the control unit (12), adjusting the valve (224) with the control unit (12) to a second position to allow at least a portion of the exhaust gas to flow from the converging cone (210) through the central bypass passage (218). [12] The method of claim 11, further comprising, after adjusting the valve (224): adjusting engine operation in response to a pressure drop across the GPF (244). [13] The method of claim 12, wherein adjusting engine operation comprises adjusting one or more of a turbocharger boost pressure, spark timing, and throttle (62), and wherein the pressure drop is based on a pressure measured upstream of the GPF (244) in the exhaust passage (202). [14] The method of claim 11, wherein adjusting the valve (224) to the first position to allow exhaust gas to flow out of the converging cone (210) and only through the peripheral passages (230) comprises: flowing exhaust gas from the converging cone (210) to an inlet of the peripheral passages (230) coupled to a wider portion of the converging cone (210), flowing exhaust gas through the peripheral passages (230), flowing exhaust gas into a diverging cone (234) forming an inlet to the GPF (244) within a housing (232) of the GPF (244), and flowing exhaust gas through filter elements of the GPF (244). [15] The method of claim 11, wherein adjusting the valve (224) to the second position comprises: flowing exhaust gas from a wider portion (212) of the converging cone (210) to a narrower portion (214) of the converging cone (210) directly coupled to an inlet into the central bypass passage (218) to direct exhaust gas into the central bypass passage (218) following a converging inner surface of the converging cone (210), and flowing exhaust gas from the central bypass passage (218) to a portion of the exhaust passage (202) downstream of the GPF (244). [16] The method of claim 11, wherein the first condition comprises one or more of a cold start condition having an engine temperature below a threshold temperature, an active regeneration event of the GPF (244), and vehicle acceleration above a threshold level. [17] The method of claim 16, wherein the second condition comprises one or more of the following: after the cold start condition, when the engine temperature is at or above the threshold temperature, or when the vehicle acceleration is not above the threshold level, and the active regeneration event of the GPF (244) does not occur. [18] The method of claim 17, wherein the first position is a fully closed position and the second position is a fully open position, and further comprising: setting the valve (224) to a third position, the third position being between the first position and the second position, during a third condition, the third condition comprising: the active regeneration event of the GPF (244), and the third position being based on a temperature of the GPF (244) and a desired regeneration temperature of the GPF (244). [19] System comprising: a gasoline particulate filter (GPF, 244) disposed in an exhaust passage (202) and having a central axis (248); a three-way catalyst (TWC, 216) disposed in the exhaust passage (202) upstream of the GPF (244); a central bypass passage (218) having a first portion (220) disposed upstream of the GPF (244) and a second portion (222) passing through a central aperture of the GPF (244) formed about the central axis (248); a converging cone (210) forming a downstream portion of a housing (204) of the three-way catalyst (216) and connecting to the first portion (220) of the central bypass passage (218); a diverging cone (234) forming an upstream portion of a housing (232) of the GPF (244) and disposed downstream of an entrance to the first portion (220) of the central bypass passage (218); a plurality of peripheral passages (230) positioned between the converging and diverging cones (210, 234) and positioned at a distance from the central passage (218); a valve (224) disposed within the first portion (220) of the central bypass passage (218); and a control unit (12) with computer-readable instructions for: Adjusting a position of the valve (224) to adjust a percentage of exhaust gas flowing through the outer passages (230) and through the GPF (244), and Adjusting engine operation in response to adjusting the position of the valve (224) and based on a pressure upstream of the GPF (244). [20] The system of claim 19, wherein the valve (224) comprises a valve plate (226) disposed within the first portion (220) of the central bypass passage (218) and a valve actuator (228), at least a portion of the valve actuator (228) being exterior to the first portion (220) of the central bypass passage (218), and wherein adjusting the position of the valve (224) comprises: increasing a degree of opening of the valve (224) to decrease the percentage of exhaust gas flowing through the outer passages (230) and through the GPF (244), and decreasing the degree of opening of the valve (224) to increase the percentage of exhaust gas flowing through the outer passages (230) and through the GPF (244).

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