Method and system for regulating exhaust flow through a post-processing device

Abstract

The present disclosure relates to methods and systems for adjusting exhaust flow through an aftertreatment device. Methods and systems are provided for a flow device that shapes flow to adjust to a radial position of an emission control device. In one example, a system can include where the flow device includes a plurality of inner openings that are aligned and a plurality of outer openings that are misaligned to flow exhaust proximal to a central axis of an exhaust passage, and where the plurality of outer openings are aligned and the plurality of inner openings are misaligned to flow exhaust distal to the central axis.

Description

[0001] Cross-reference of related applications

[0002] This application claims priority to German patent application No. 102018203300.5, filed on March 6, 2018. The entire contents of the aforementioned application are incorporated herein by reference for all purposes. Technical Field

[0003] This specification relates primarily to methods and systems for arranging exhaust aftertreatment in internal combustion engines, wherein exhaust gas may selectively pass through a nitrogen oxide storage catalytic converter or an oxidation catalytic converter, depending on engine operating conditions. Background Technology

[0004] To meet current and future emission requirements for internal combustion engines, stringent demands are placed on exhaust aftertreatment. This necessitates the effective operation of the corresponding exhaust aftertreatment devices across the entire operating range of the internal combustion engine. Known methods for catalytic-assisted exhaust cleaning operate effectively under varying boundary conditions. Therefore, it is desirable to incorporate one or more different catalysts into the exhaust aftertreatment arrangement to treat exhaust pollutants over a wider range of engine operating conditions.

[0005] To remove nitrogen oxides from exhaust gases, a nitrogen oxide storage catalytic converter (also known as a NOx catalytic converter) is used. x Storage catalytic converter or dilute NO x Nitrogen oxide traps (LNTs) and / or catalytic converters are used for selective catalytic reduction (SCR). LNTs can be used to adsorb nitrogen oxides from the exhaust of internal combustion engines. Furthermore, they can perform oxidative aftertreatment of carbon monoxide (CO) and hydrocarbons (HC). Nitrogen oxides produced in lean mode of an internal combustion engine can be stored in LNTs. LNTs can oxidize nitric oxide (NO) contained in lean exhaust to form nitrogen dioxide (NO2), which is then stored as nitrates. For example, the adsorbent used for LNT coatings can be barium oxide and / or other oxides.

[0006] If the LNT's storage capacity is depleted (e.g., the LNT is fully loaded and cannot adsorb more nitrogen dioxide), regeneration of the LNT may be necessary. In the case of a regeneration event (purification), substoichiometric exhaust conditions are provided, for example, by operating an internal combustion engine with a fuel-rich air mixture (e.g., λ < 1). In this example, the stored nitrogen oxides are desorbed again and reduced to nitrogen in the catalytically active component of the LNT using components from the rich exhaust (CO, HC). Besides rich engine operation initiated for regeneration, the LNT may also be regenerated if the exhaust is substoichiometric, for example, due to the drive requirements of the internal combustion engine. To reduce desorbed nitrogen oxides that were not reduced in the LNT, a catalytic converter located downstream can be provided for selective catalytic reduction (SCR).

[0007] In catalytic converters used for selective catalytic reduction (SCR), nitrogen oxides are reduced to gaseous nitrogen and water using a reducing agent (e.g., ammonia). For this purpose, ammonia can be prepared as an aqueous solution of urea (e.g.,...). The nitrogen oxides (NOx) are introduced into the exhaust system upstream of the SCR in the form of nitrogen oxides (NOx), which are hydrolyzed into ammonia and carbon dioxide. Ammonia can also be introduced into the exhaust system in gaseous form, or it can be generated in the case of LNT regeneration and can enter the SCR located downstream. In all cases, ammonia can be stored in the SCR to reduce NOx to nitrogen under lean exhaust conditions.

[0008] The temperature window providing the required LNT efficiency is in the range of 150°C to 500°C, while the SCR temperature window is in the range of 200°C to 500°C. In this case, LNT operates particularly well in the lower temperature window of the internal combustion engine under low to medium load conditions. This operating mode occurs particularly frequently when motor vehicles are used in urban environments with low exhaust temperatures (e.g., below 200°C).

[0009] The effective and therefore purposeful operating mode of the SCR catalytic converter exists at exhaust temperatures above 200°C. Therefore, due to its high conversion efficiency, SCR is required at the high-load, high-emission operating points of internal combustion engines. This operating mode is particularly frequently observed when using motor vehicles outside of urban environments (e.g., highway driving).

[0010] Another component used in catalytic exhaust aftertreatment is the oxidation catalytic converter. This component is used to remove (e.g., oxidize) carbon monoxide and hydrocarbons from the exhaust of internal combustion engines (especially automatic ignition internal combustion engines). In this process, carbon monoxide is oxidized to carbon dioxide, and hydrocarbons are oxidized to carbon dioxide and water. The reduction of nitrogen oxides is not favorable in the oxidation catalytic converter. Therefore, nitrogen oxides are reduced in LNT and / or SCR.

[0011] However, LNTs have the disadvantageous property of changing the nitrogen dioxide to nitric oxide ratio from 50:50 (which is advantageous for SCR operation) to a higher nitric oxide component (e.g., 1:2 or lower). Therefore, it is desirable to regulate the exhaust flow rate so that LNTs are not used at certain temperatures, some of which coincide with the effective operating temperature. Therefore, the object of the present invention is to improve exhaust aftertreatment related to the reduction of nitrogen oxides. Summary of the Invention

[0012] In one example, the aforementioned problem can be addressed by a system comprising a flow device shaped to direct exhaust gas flow to an external or internal region of an emission control device. This flow device includes a rotatable first plate and a fixed second plate, each comprising an internal opening and an external opening, wherein the alignment of the internal and external openings is adjusted via rotation of the first plate. In this way, the exhaust gas flow through the emission control device can be adjusted based on engine operating conditions and estimated efficiency of different regions of the emission control device.

[0013] In one example, this disclosure includes an arrangement of an internal combustion engine having an exhaust system, wherein at least one oxidation catalytic converter and at least one first nitrogen oxide storage catalytic converter are disposed in a common first catalytic converter device, at least one first catalytic converter for selective catalytic reduction and at least one particulate filter are disposed downstream of the first catalytic converter device, and at least one delivery device for a reducing agent is disposed upstream of the catalytic converter for selective catalytic reduction, wherein the first catalytic converter device includes an outer region and an inner region, and wherein a switching device for controlling exhaust flow is disposed at the upstream end and is configured to allow exhaust to pass through the inner region in a first operating mode and through the outer region in a second operating mode.

[0014] It should be understood that the above description of the invention is provided to present a series of concepts further described in the detailed embodiments in a simplified form. This is not intended to identify key or essential features of the claimed subject matter, the scope of which is uniquely defined by the appended claims. Furthermore, the claimed subject matter is not limited to embodiments that address any shortcomings mentioned above or in any part of this disclosure. Attached Figure Description

[0015] Figure 1 A schematic representation of an embodiment of the arrangement according to the present disclosure is shown.

[0016] Figure 2 The basis for being in the first working mode is shown. Figure 1 An embodiment of the switching device in the arrangement.

[0017] Figure 3The basis for being in the second working mode is shown. Figure 2 The switching device.

[0018] Figure 4 It shows that it has the following characteristics: Figure 1 The arrangement of the first catalytic converter unit according to Figure 2 and Figure 3 The switching device.

[0019] Figure 5 The basis for being in the first working mode is shown. Figure 1 The arrangement.

[0020] Figure 6 The basis for being in the second working mode is shown. Figure 1 The arrangement.

[0021] Figure 7 A flowchart illustrating an embodiment of the method according to this disclosure is shown.

[0022] Figure 8 A schematic diagram illustrating an embodiment of the method according to this disclosure is shown.

[0023] Figures 2 to 3 The figures are shown to approximate scale, but other relative dimensions may be used if needed.

[0024] Figure 9 A schematic diagram of the engine in a hybrid vehicle is shown.

[0025] Figure 10 The diagram shows a pre-defined engine operation sequence, illustrating the adjustment of vehicle operating parameters and switching devices. Detailed Implementation

[0026] The following description relates to systems and methods for flow devices and / or switchable components that are shaped to regulate exhaust flow to different radial positions of an emission control device. Figure 1 A schematic representation of an embodiment of the arrangement according to the present disclosure is shown. Figure 2 The basis for being in the first working mode is shown. Figure 1 An embodiment of the switching device in the arrangement. Figure 3 The basis for being in the second working mode is shown. Figure 2 The switching device. Figure 4 It shows according to Figure 2 and Figure 3 The switching device has the following characteristics: Figure 1 The first catalytic converter unit is arranged in a specific configuration. Figure 5 The basis for being in the first working mode is shown. Figure 1 The arrangement. Figure 6 The basis for being in the second working mode is shown. Figure 1 The arrangement. Figure 7 A flowchart illustrating an embodiment of the method according to this disclosure is shown. Figure 8 A schematic diagram illustrating an embodiment of the method according to this disclosure is shown. Figure 9 A schematic diagram of the engine in a hybrid vehicle is shown. Figure 10 The diagram shows the predicted engine operation sequence and the adjustment of vehicle operating parameters and switching devices.

[0027] The arrangement according to this disclosure at least partially solves the aforementioned problems by equipping the exhaust aftertreatment system with a switchable component. The switchable component is interchangeably referred to herein as a flow device. This allows for the regulation of the exhaust flow through a suitable control strategy. Advantageously, the exhaust flow can be delivered according to function-related operating parameters to maximize the system's cleaning efficiency for different components based on their performance attributes.

[0028] In one example, the internal combustion engine is an auto-ignition internal combustion engine (e.g., a diesel engine). Therefore, the particulate filter is a diesel particulate filter. However, it should be understood that switchable components of the exhaust system can be implemented in the exhaust system of a spark-ignition engine without departing from the scope of this disclosure. Those skilled in the art will understand that temperature thresholds, etc., as described below, can be adjusted to arrange the switchable device in the exhaust system of a spark-ignition engine because the exhaust temperature therein is higher compared to a diesel engine exhaust system.

[0029] The switching device is shaped to selectively direct exhaust flow through external and / or internal regions of the first catalytic converter unit. For this purpose, the switching device includes openings for allowing exhaust flow, which are correspondingly at least partially opened and closed.

[0030] In this arrangement, the oxidation catalytic converter is preferably located in the external region of the first catalytic converter unit. The external location of the oxidation catalytic converter is advantageous because it achieves good thermal coupling with the environment. As a result, overheating of the exhaust aftertreatment components can be avoided.

[0031] In this arrangement, the nitrogen oxide storage catalytic converter (LNT) is preferably located in the internal region of the first catalytic converter unit. The internal location of the LNT is desirable because it achieves increased thermal isolation relative to the external region. Therefore, temperature loss is minimized, and the catalytic converter can operate at optimal efficiency within a typical temperature window (150°C to 350°C). In other words, the internal region can be hotter than the external region because the external region is in coplanar contact with the surface of the exhaust pipe, where thermal communication with the exhaust pipe allows the cooler ambient temperature (e.g., ambient air) to lower the temperature of the external region, while the temperature of the internal region remains relatively constant.

[0032] In the arrangement according to this disclosure, a catalytic converter and a particulate filter for selective catalytic reduction can be arranged in a second catalytic converter unit. In this case, the units can also be combined with each other (e.g., the particulate filter may include a coating used as an SCR). The integration of the filter and SCR allows for an arrangement close to the internal combustion engine, which has a favorable impact on operation because it enables higher temperatures in the second catalytic converter unit. Furthermore, this combination saves space and reduces packaging constraints.

[0033] It is desirable to achieve a uniform distribution of the introduced reductant on the filter of a particulate filter with an SCR coating, so that the SCR function can be used throughout the filtration area. Therefore, a mixer for the fluid medium can be arranged in the exhaust system upstream of the catalytic converter for selective catalytic reduction.

[0034] The oxidation catalytic converter is preferably optimized for high conversion efficiency from nitric oxide to nitrogen dioxide. Therefore, it is advantageous to adjust the ratio of nitric oxide to nitrogen dioxide to 50:50, which can improve the conversion efficiency of SCR.

[0035] Another embodiment of this disclosure relates to a motor vehicle having an arrangement according to this disclosure.

[0036] Further embodiments of this disclosure relate to a method for controlling an exhaust aftertreatment system having an arrangement according to this disclosure. The method includes operating an internal combustion engine, determining a first exhaust temperature in a region upstream of a first catalytic converter device, switching a switching device to a first operating mode if the first exhaust temperature is less than or equal to a first temperature threshold, and switching the switching device to a second operating mode if the first exhaust temperature is greater than the first threshold, determining an exhaust velocity near the first catalytic converter device, and placing the switching device in the first operating mode if the velocity is less than or equal to a velocity threshold, and switching to the second operating mode if the velocity is greater than the threshold.

[0037] Furthermore, since SCR can be effectively used to reduce nitrogen oxides at high temperatures and high exhaust velocities, it is desirable to switch the switching device to a second operating mode. This is likely desirable at the high-load operating point of the internal combustion engine. Therefore, the first operating mode directs exhaust gas to a first section of the first catalytic converter, which is configured to process nitrogen oxides. The second operating mode directs exhaust gas to a second section of the first catalytic converter, which is configured to process hydrocarbons and exhaust components other than nitrogen oxides. Thus, the conditions of the second operating mode can be such that nitrogen oxide conversion at the SCR (e.g., the second catalytic converter) is more favorable than at the first section of the first catalytic converter.

[0038] To determine the temperature and velocity of the exhaust gas, sensors are, for example, installed in the exhaust system. Alternatively or additionally, the parameters mentioned may also be determined based on a model.

[0039] A second exhaust temperature near the SCR can be sensed via a sensor, and if the second exhaust temperature is greater than or equal to a second temperature threshold, a reducing agent is introduced into the exhaust system via a delivery device; if the second exhaust temperature is lower than the second temperature threshold, no reducing agent is introduced into the exhaust system. In this case, especially at the high temperature of the second threshold, a reducing agent is introduced because ammonia previously stored in the SCR (which is formed, for example, during regeneration in the LNT and transferred to the SCR) escapes from the SCR by slip at high temperatures and may be insufficient for the reduction of nitrogen oxides.

[0040] Furthermore, when the switching device is switched to the second operating mode, a nitrogen dioxide to nitric oxide ratio of 50% is desirable. This 50% ratio of nitrogen dioxide to nitric oxide improves the reduction efficiency in SCR, particularly the ammonia-related reduction efficiency. In this case, an oxidation catalytic converter is desirable because, in addition to converting carbon monoxide and hydrocarbons, the oxidation catalytic converter is implemented to at least partially oxidize nitric oxide to nitrogen dioxide. The ratio of nitrogen oxides can be influenced by corresponding optimizations of the oxidation catalytic converter, which will be apparent to those skilled in the art.

[0041] Furthermore, in this method, the switching device additionally switches to either a first operating mode or a second operating mode based on the operating point of the internal combustion engine. At high-load operating points where relatively hot exhaust gases are produced, the second operating mode is advantageous because the exhaust gases are then passed to the SCR via an oxidation catalytic converter, which operates more efficiently than the LNT at higher temperatures. Moreover, the LNT is unaffected by high temperatures. The SCR can be expected to operate within a temperature window of 250°C to 500°C, and preferably maintains this temperature window for efficient SCR operation. At low-load operating points where relatively cool exhaust gases are produced, the first operating mode is advantageous because the lower operating temperature of the LNT (150°C to 350°C) can therefore be used for efficient exhaust aftertreatment. In this case, in addition to converting carbon monoxide and hydrocarbons, the LNT can also store nitrogen oxides. Ammonia generated during the LNT's cycle regeneration can be stored by the downstream SCR (or a particulate filter coated with an SCR) and used for subsequent nitrogen oxide reduction at higher temperatures.

[0042] Furthermore, in this method, the switching device is additionally switched to a first operating mode or a second operating mode based on different combinations of parameters in the 3D mapping sense of the control of the internal combustion engine. As a result, further parameters can be advantageously incorporated into the control of exhaust aftertreatment.

[0043] Figures 1 to 6 and Figure 9 Example configurations with relative positioning of various components are shown. If shown as being in direct contact or directly coupled to each other, then in at least one example, such components may be referred to as being in direct contact or directly coupled, respectively. Similarly, components shown as being adjacent or close to each other may be referred to as being adjacent or close to each other, respectively, in at least one example. As an example, components that are in coplanar contact with each other may be referred to as being in coplanar contact. As another example, components positioned separately from each other, with only space between them and no other components, may be referred to in at least one example. As yet another example, components shown above / below each other, on opposite sides of each other, or to the left / right of each other may be referred to in this way relative to each other. Furthermore, as shown, in at least one example, the topmost component or the topmost point of the component may be referred to as the “top” of the component, while the bottommost component or the bottommost point of the component may be referred to as the “bottom” of the component. As used herein, top / bottom, upper / lower, above / below may be relative to the vertical axis of the figure and used to describe the positioning of the components of the figure relative to each other. Thus, in one example, a component shown above other components is vertically positioned above the other components. As yet another example, the shapes of the elements shown in the figure may be described as having those shapes (e.g., such as circles, straight lines, planes, curves, fillets, chamfers, bevels, etc.). Furthermore, in at least one example, elements shown as intersecting each other may be described as intersecting elements or intersecting each other. Additionally, in one example, elements shown inside or outside another element may be described as intersecting elements or intersecting each other. It should be understood that one or more parts described as “substantially similar and / or identical” differ from each other according to manufacturing tolerances (e.g., within a deviation of 1% to 5%).

[0044] Notice, Figures 5 to 6 Arrows are shown indicating the presence of spaces for gas flow, and solid lines on the equipment walls indicate locations where flow is blocked and communication is impossible due to the lack of fluid connectivity created by the equipment walls spanning from one point to another. Apart from openings in the walls (which allow the described fluid connectivity), the walls create separation between areas.

[0045] Now go to Figure 1 This illustration shows an embodiment of arrangement 1 according to the present disclosure for exhaust aftertreatment. In arrangement 1, an exhaust system 2 is shown for passing exhaust gas from an internal combustion engine. The internal combustion engine may be a self-igniting internal combustion engine. In this case, the arrangement may also be alternatively used for exhaust gas from an externally ignited internal combustion engine. Arrow 17 indicates the flow direction of the exhaust gas in exhaust system 2.

[0046] The first catalytic converter device 3 is disposed in the exhaust system 2. The first catalytic converter device 3 includes a first (internal) region 31 and a second (external) region 32. A nitrogen oxide storage catalytic converter 4 (LNT) is disposed in the first region 31 and a diesel oxidation catalytic converter 5 (DOX or DOC) is disposed in the second region 32.

[0047] The volume of the first region 31 may be substantially equal to the volume of the second region 32. Alternatively, the volume of the first region 31 may be greater than or less than the volume of the second region 32. The second region 32 is radially outside the first region 31, wherein the second region 32 and the first region 31 are concentric with respect to the central axis of the exhaust passage of the exhaust system 2. In this way, the second region 32 can be pressed against the surface of the exhaust pipe that shapes the exhaust passage, thereby at least partially isolating the first region 31 from the exhaust pipe and the environment (such as the ambient atmosphere) directly outside the pipe.

[0048] A switching device 6 is disposed upstream of the first catalytic converter device 3. The switching device 6 is configured to selectively allow exhaust flow through the second region 32 and / or the first region 31 of the first catalytic converter device 3. To this end, the switching device 6 includes a switchable opening for allowing exhaust flow to pass through, which can be at least partially opened and closed accordingly.

[0049] One embodiment of the switching device 6 includes a first plate 61 and a second plate 62. Figures 2 to 4 The plates may be circular, corresponding to the shape of the first catalytic converter device 3. However, depending on the shape of the first catalytic converter device 3 and the exhaust system 2, the shape of the plates may be square, triangular, or other shapes. Each plate includes an inner region (611 or 621) and an outer region (612 or 622), in each of these regions forming a plurality of evenly spaced openings 63. The openings are implemented and arranged such that the corresponding openings 63 of the inner regions 611, 621 or the outer regions 612, 622 can be aligned with each other at specific locations on the plates 61 and 62.

[0050] In each case, a specific distance in the circumferential direction is provided between the openings 63, sized such that, at a specific position relative to each other in the regions of plates 61 and 62, an opening 63 of one valve plate can be covered by the material of the other valve plate. In the first plate 61, the opening 63 of the inner region 611 is configured to be offset relative to the opening 63 of the outer region 612. The openings 63 of the inner region 621 and the outer region 622 of the second plate 62 are not configured to be offset relative to each other. The rotational movement of the plates relative to each other is caused by an actuator 64, which is connected to one of the plates via an adapter 65. The movement of the plates relative to each other is controlled by a control device 7 that actuates the actuator 64.

[0051] The internal regions of plates 611 and 621 are flush-coupled to the internal region 31 of the catalytic converter device 3. Figure 4 The outer regions of plates 621 and 622 are flush-coupled to the outer region 32 of the catalytic converter device 3. Figure 4 In the first operating mode of the switching device 6, an operation is provided in which the plates 61 and 62 are adjusted such that the openings 63 in the internal regions of the plates 611 and 621 at least partially overlap each other. Figure 2 In this case, the openings 63 completely overlap each other (e.g., arranged so that one is flush with the other). Meanwhile, in this case, the openings 63 in the outer regions of plates 612, 622 do not overlap each other, so that they are closed to each other. In this way, exhaust gas is deflected through the openings 63 in the inner regions 611, 621 of the switching device 6 and thus through the LNT 4 (located in the inner region 31 of the first catalytic converter device 3). Figure 5 ).

[0052] In the second operating mode of the switching device 6, an operation is provided in which plates 61 and 62 are adjusted such that the openings 63 in the outer regions of plates 612 and 622 at least partially overlap each other. Figure 3 In this configuration, the openings 63 completely overlap each other, i.e., they are arranged so that one is flush with the other. Meanwhile, the openings 63 in the inner regions of plates 611 and 621 do not overlap each other, so that they are closed to each other. In this way, exhaust deflection occurs through the openings 63 in the outer regions 612 and 622 of the switching device 6 and therefore through the DOX 5 located in the outer region 32 of the first catalytic converter device 3. Figure 6 ).

[0053] The openings 63 of the inner regions 611, 621 and the outer regions 612, 622 may also overlap in the third operating mode. In this case, the exhaust will pass through LNT 4 and DOX 5.

[0054] In an alternative embodiment, the switching device 6 includes the openings, which can be actuated and correspondingly opened and closed. For this purpose, for example, fins connected to actuators can be provided on the openings.

[0055] The second catalytic converter unit 8 is located downstream of the first catalytic converter unit 3. A catalytic converter for selective reduction 9 (SCR) and a diesel particulate filter 10 are located in the second catalytic converter unit 8. The SCR 9 and the filter 10 may be provided individually or in combination with each other, for example in the form of an SCR coating on the filter 10.

[0056] A delivery device 11 for introducing a reducing agent into the exhaust system 2 is located upstream of the second catalytic converter device 8. A reducing agent is provided to reduce nitrogen oxides in the SCR 9. This is particularly done with an aqueous solution of urea (e.g., urea solution). The urea solution is introduced into exhaust system 2 as a reducing agent, where it is hydrolyzed into water and ammonia. If the delivery device 11 is a nozzle, the urea solution can be introduced in liquid form or, for example, even injected. Gaseous ammonia can also be introduced into exhaust system 2.

[0057] To distribute the introduced reducing agent more evenly, a mixer 12 is positioned near the delivery device 11 in the exhaust system 2. The mixer 12 includes, for example, multiple blades on which the exhaust flow impinges, thus creating turbulence in the reducing agent introduced into the exhaust system 2. The mixer 12 is positioned downstream of the delivery device 11 in the exhaust system 3.

[0058] At least one temperature sensor 13 is located upstream of the first catalytic converter unit 3 in the exhaust system 2. Another temperature sensor 13 is located upstream of the second catalytic converter unit 8. The temperature sensors 13 are connected to a control unit 7, to which the measured values ​​are transmitted. At least one flow sensor 14 is located in each of the LNT 4 and DOX 5. The flow sensors 14 are also each connected to the control unit 7, to which the measured values ​​are transmitted. The sensors may be located at different points in the exhaust system 2, and other sensors (e.g., pressure sensors, nitrogen oxide sensors, and / or oxygen sensors) may also be located in this manner.

[0059] in other words, Figure 2 and Figure 3 A switching device 6 (interchangeably referred to as a flow device 6 or flow control device 6) including a first plate 61 and a second plate 62 is shown. Each of the first plate 61 and the second plate 62 includes an opening 63. The opening 63 may include a plurality of internal openings 222 and a plurality of external openings 232. The plurality of internal openings 222 may be evenly distributed and spaced apart from each other, such that segments of the first plate 61 and the second plate 62 are arranged between each of the internal openings 222 and block the exhaust flow. In one example, the segments and internal openings 222 may be similarly sized such that a single segment can block and block a single internal opening of the internal opening 222, thereby blocking the airflow through the single internal opening. In one example, the segments between the plurality of internal openings 222 are radially internal segments, and the segments between the plurality of external openings 232 are radially external and / or outer segments.

[0060] Multiple external openings 232 may be evenly distributed and spaced apart from each other, such that segments of the first plate 61 and the second plate 62 are arranged between each of the external openings 232 and block the exhaust flow. In one example, the segments and external openings 232 may be similarly sized such that a single segment can block and obstruct a single external opening of the external opening 232, thereby blocking the airflow through the single external opening.

[0061] Thus, the first plate 61 includes an internal opening 222 and an external opening 232. Similarly, the second plate 62 includes an internal opening 222 and an external opening 232. The dimensions of the first plate 61 and the second plate 62 may be similarly set such that the internal opening 222 or the external opening 232 may be aligned at some positions of the first plate 61 or the second plate 62, allowing exhaust gas to flow through the internal opening 222 or the external opening 232.

[0062] In one example, the internal opening 222 and the external opening 232 are arranged such that when the internal opening 222 of the first plate 61 and the second plate 62 are fully aligned, the external opening 232 of the first plate 61 and the second plate 62 are completely misaligned. Thus, when the internal opening 222 is aligned, the sections of the first plate 61 and the second plate 62 that block the exhaust flow are aligned with the external opening 232. Conversely, when the external opening 232 is fully aligned, the internal opening 222 is completely misaligned. When the internal opening 222 is fully aligned, exhaust gas can flow through the internal opening 222 but not through the external opening 232 to the first internal region 31 (e.g., LNT4) of the first catalytic converter device 3. When the external opening 232 is fully aligned, exhaust gas can flow through the external opening 232 (but not through the internal opening 222) to the second external region 32 (e.g., DOC5) of the second catalytic converter device 3. Thus, partial alignment of the internal opening 222 can also result in partial alignment of the external opening 232, thereby causing exhaust gas to flow to the first internal region 31 and the second external region 32 of the second catalytic converter device 3.

[0063] In one example, one of the first plate 61 or the second plate 62 is fixed, while the other plate is actuable (e.g., pivotable and / or rotatable) to adjust the alignment of the inner opening 222 and the outer opening 232. In one example, the first plate 61 is movable, while the second plate 62 is fixed. The switching device 6 may include a pair of end tabs 242 for limiting the actuation of the adapter 65. The adapter may include tab shapes, wherein the adapter is oriented in a direction perpendicular to the pair of end tabs 242. The adapter 65 may be actuated between the pair of end tabs 242, wherein contact with the first end tab 242A may correspond to a first operating position ( Figure 2 ), and the contact with the second end tab 242B can correspond to the second working position ( Figure 3 Thus, adapter 65 is in Figure 2 The example shows the first working position and Figure 3 The examples show movement between the second working positions by some angular amount. In some examples, the angular amount is less than 10 degrees. In some examples, additionally or alternatively, the angular amount is less than 8 degrees. In some examples, additionally or alternatively, the angular amount is less than 7 degrees. In some examples, additionally or alternatively, the angular amount is less than 5 degrees. In one example, the angular amount is less than 4 degrees.

[0064] In accordance with this disclosure, for use via pursuant to Figure 1 According to the equipment Figure 7 In one embodiment of the method for controlling exhaust aftertreatment, the internal combustion engine is operated in a first step S1. In a second step S2, the exhaust temperature in the upstream region of the first catalytic converter device 3 is determined. In this case, the value is measured by temperature sensor 13 and transmitted to control device 7. Alternatively, the temperature can be determined based on a model.

[0065] In the third step S3, if the exhaust temperature is less than or equal to a first temperature threshold, the switching device 6 is switched to the first operating mode. Figure 5 For this purpose, the control device 7 sends a corresponding control command to the actuator 64 of the switching device 6, which sets the opening in the internal region of the switching device 6 to allow flow. If the exhaust temperature is greater than a first threshold, the switching device 6 is switched to a second operating mode. Figure 6 For this purpose, the control device 7 issues a corresponding control command to the actuator of the switching device 6, which sets the opening in the external region of the switching device 6 to allow flow. If the switching device 6 is already in the first operating mode, it remains in the first operating mode if the exhaust temperature is less than or equal to a first threshold. If the switching device 6 is already in the second operating mode, it remains in the second operating mode if the exhaust temperature is greater than the first threshold.

[0066] In step S4, the exhaust velocity is determined. For example, if the switching device 6 is in the first operating mode, the velocity is determined in the volume of LNT 4; or if the switching device 6 is in the second operating mode, the velocity is determined in DOX 5. If the exhaust velocity is less than or equal to a threshold, the switching device switches to the first operating mode in step S5, or remains in the first operating mode if it is already in the first operating mode. If the exhaust velocity is greater than the threshold, the switching device 6 switches to the second operating mode, or remains in the second operating mode if it is already in the second operating mode.

[0067] Turn now Figure 8It illustrates a method 800 for adjusting the operating position of a switching device. Instructions for implementing this method can be generated by a controller and / or control device based on instructions stored in the controller's memory and in conjunction with information from sensors in the engine system (such as reference sensors). Figures 1 to 9 The controller uses signals received by the sensor described below to perform actions. According to the method described below, the controller can employ the engine actuator of the engine system to regulate engine operation.

[0068] Method 800 begins at 802, which includes determining, estimating, and / or measuring current engine operating parameters. Current engine operating parameters may include, but are not limited to, one or more of manifold vacuum, throttle position, engine speed, engine load, engine temperature, vehicle speed, and air / fuel ratio.

[0069] Method 800 proceeds to 804, where 804 may include determining whether a first exhaust temperature is greater than a first threshold temperature. The first exhaust temperature may be determined via a device arranged in the first catalytic converter (e.g., Figure 1 The first catalytic converter unit 3) upstream of the LNT measures and / or senses a temperature sensor. The first threshold temperature may be based on the desired operating temperature of the LNT. In one example, the first threshold temperature may be based on the desired operating temperature of the SCR unit downstream of the LNT. In one example, the first threshold temperature is a non-zero positive number, such as 200°C. As described above, the LNT may be arranged along the internal region of the first catalytic converter unit.

[0070] If the exhaust temperature is not lower than the first threshold temperature, then method 800 proceeds to 806 to enter the second operating mode. Method 800 proceeds to 808, where 808 includes enabling the flow device (e.g., Figures 1 to 6 The switching device 6) rotates in the second direction, causing the adapter to contact the second end tab. In this way, the outer opening of the flow device is aligned, and the inner opening is misaligned, allowing exhaust gas to flow only through the outer opening and not through the inner opening. In some examples, step 808 may be omitted if the flow device was previously in a position corresponding to the second operating position. However, if the flow device was previously in a position corresponding to the first operating position, step 808 is performed, and a portion of the flow device is rotated to misalign the inner opening and align the outer opening.

[0071] Method 800 proceeds to 810, whereby exhaust gas is allowed to flow through an external region of the first catalytic converter unit, which corresponds to the DOC portion of the unit. Therefore, during the second operating mode, exhaust gas may not flow through the LNT of the first catalytic converter unit.

[0072] Returning to 804, if the exhaust temperature upstream of the first catalytic converter device is less than a first threshold temperature, then method 800 proceeds to 812, whereby 812 includes determining whether the volumetric flow rate of the exhaust gas to the first catalytic converter device is less than a threshold. In one example, the threshold may correspond to the exhaust flow rate under lower engine loads. For example, lower engine loads may occur during city / urban driving or other driving conditions with relatively low vehicle speeds and relatively high stopping frequency. Therefore, higher engine loads may occur during highway driving and / or during acceleration corresponding to hard pressing of the accelerator pedal.

[0073] If the volumetric exhaust flow to the first catalytic converter is not less than a threshold, then method 800 proceeds as described above to 806 and enters a second operating mode, causing the exhaust to flow through the external region of the first catalytic converter. Therefore, the second operating mode can correspond to an operating mode in which the SCR device arranged in the second catalytic converter downstream of the first catalytic converter, relative to the direction of the exhaust flow, satisfies a condition, thereby reducing exhaust with a higher efficiency than the LNT of the first catalytic converter. In this way, the exhaust is directed to the DOC in the external region of the first catalytic converter, instead of flowing through the LNT.

[0074] Returning to 812, if the volumetric flow rate of the exhaust gas flowing to the first catalytic converter is less than a threshold and its temperature is predetermined to be less than a first threshold temperature, then method 800 proceeds to 814 to enter a first operating mode. Method 800 proceeds to 816, which includes causing the flow device (e.g., Figures 1 to 6 The switching device 6) rotates in the first direction so that the adapter can contact the end of the first tab (e.g., Figure 2 and Figure 3 The first tab end 242A). In this way, the inner opening can be aligned and the outer opening can be misaligned, thereby blocking the exhaust flow through the outer opening. If the flow device was previously in the first operating position, step 816 can be omitted because the adapter has already contacted the first tab end. However, if the flow device was in the second operating position before 816, the flow device rotates in the first direction opposite to the second direction to enter the first operating mode.

[0075] Method 800 proceeds to 818, 818 including allowing exhaust gas to flow through an internal region of the first catalytic converter device. Alternatively or additionally, the first operating mode includes allowing exhaust gas to flow through the internal region without allowing exhaust gas to flow through an external region of the first catalytic converter device. In this way, exhaust gas flows through aligned internal openings but not through misaligned external openings, and enters an LNT disposed within the internal region of the first catalytic converter device.

[0076] Method 800 proceeds to 820 after 818 or 810, which includes directing exhaust flow to a second catalytic converter device, which may be an SCR arranged downstream of the first catalytic converter device relative to the direction of exhaust flow.

[0077] Method 800 proceeds to 822, whereby 822 includes determining whether the exhaust temperature of the exhaust gas flowing to the second catalytic converter device is greater than or equal to a second threshold temperature. The exhaust temperature can be sensed downstream of the first catalytic converter device and upstream of the second catalytic converter device (e.g., SCR). The second threshold temperature can be based on the exhaust temperature from which reductant can be removed from the second catalytic converter device. In one example, the second threshold temperature is greater than a first threshold temperature. Thus, detecting an exhaust temperature greater than or equal to the second threshold temperature preemptively determines a reductant request.

[0078] If the exhaust temperature is greater than or equal to the second threshold temperature, method 800 proceeds to 824, which may include injecting a reducing agent into a portion of the exhaust passage between the first and second catalytic converter devices. In this way, the reducing agent can be injected during either a first or second operating mode. The injection may be performed via an injector positioned to directly inject the reducing agent into the exhaust passage towards the surface of the second catalytic converter device. In some examples, additionally or alternatively, a mixing device may be arranged between the injector and the second catalytic converter device to promote uniform distribution of the reducing agent across the entire surface of the second catalytic converter device.

[0079] If the exhaust temperature is not greater than or equal to the second threshold temperature, method 800 proceeds to 826, 826 including not injecting the reductant into the exhaust passage toward the second catalytic converter device. This conserves the reductant stored in the reductant reservoir, while the exhaust temperature is insufficient to remove the reductant from the second catalytic converter device.

[0080] In other words, alternatively or additionally, method 800 includes detecting exhaust-related operation-related parameters, particularly exhaust temperature and exhaust velocity, during operation of the internal combustion engine of a motor vehicle. These parameters are determined based on sensors or models. If a first temperature value T1 of the exhaust temperature detected upstream of the first catalytic converter device 3 is greater than a first temperature threshold T... S1 Then the exhaust gas passes through the DOX. If the exhaust temperature T1 is less than or equal to the first threshold temperature T... S1 Then determine the volumetric flow rate v of the exhaust gas. A If the volumetric flow rate v of the exhaust gas A The volumetric flow rate v of the exhaust gas is greater than the threshold value. AS Even if the exhaust temperature T1 is less than the first temperature threshold T S1The exhaust also passes through DOX 5. If the exhaust volumetric flow rate v A The threshold v for exhaust volumetric flow rate that is less than or equal to the exhaust volumetric flow rate AS If the exhaust temperature T1 is also less than or equal to the first temperature threshold T S1 Then the exhaust passes through LNT 4.

[0081] After flowing through LNT 4 and DOX 5, the exhaust flows downstream to SCR 9 or the second catalytic converter device 8. Depending on the exhaust temperature, a reducing agent is introduced into the exhaust system 2 via delivery device 11. For this purpose, a second temperature value T2 is determined near SCR 9, for example, directly upstream of the second catalytic converter device 8. If the exhaust temperature is greater than or equal to a second threshold temperature T... S2 Then a reducing agent is introduced. If the exhaust temperature T2 is less than the second temperature threshold T... S2 If no reducing agent is introduced, then the method continues at the first temperature T. S1 The detection is performed and compared with a threshold.

[0082] Figure 9 A schematic diagram of a hybrid vehicle system 906 is shown, which can obtain propulsion power from an engine system 908 and / or an onboard energy storage device. Operable energy conversion devices (such as generators) can absorb energy from vehicle motion and / or engine operation, and then convert the absorbed energy into an energy form suitable for storage by the energy storage device.

[0083] Engine system 908 may include engine 910 having multiple cylinders 930. Engine 910 includes engine intake device 923 and engine exhaust device 925. Engine intake device 923 includes intake throttle valve 962 fluidly coupled to engine intake manifold 944 via intake passage 942. Air may enter intake passage 942 via air filter 952. Engine exhaust device 925 includes exhaust manifold 948 leading to exhaust passage 935, which delivers exhaust gas to the atmosphere. Engine exhaust device 925 may include one or more emission control devices mounted in a closely coupled or distal underbody location. One or more emission control devices may include a three-way catalytic converter, lean NO... x This includes components such as a filter trap, a diesel particulate filter, and an oxidation catalyst. It should be understood that the engine may include other components, such as various valves and sensors, as further detailed herein. In some embodiments, where engine system 908 is a turbocharged engine system, the engine system may also include a supercharging device, such as a turbocharger (not shown).

[0084] In one example, emission control device 970 is a first emission control device arranged upstream of second emission control device 972 relative to the direction of exhaust flow. Volume sensor 974 may be arranged at the junction between first emission control device 970 and flow control device 976. Alternatively, temperature sensor 128 may be arranged upstream of first emission control device 970.

[0085] In one example, the first emission control device 970 can be coupled with Figure 1 The first catalytic converter device 3 is used similarly. Thus, in one example, the first emission control device 970 is a combined catalyst that may include nitrogen oxide capture capability and oxidation catalyst functionality. More specifically, the first emission control device 970 may include an internal region 970A with LNT catalyst capability and an external region 970B with oxidation catalyst capability. The internal region 970A may be fluidly separated from the external region 970B such that exhaust gas in the external region 970B does not mix with exhaust gas in the internal region 970A.

[0086] Can be with Figure 1 The switching device 6 similarly uses a flow control device 976 which can be positioned directly upstream of the first emission control device 970. The flow control device 976 can be adjusted in response to feedback from one or more of the temperature sensor 128 and the volume sensor 974, as described above with respect to method 800. The flow control device 976 includes an inner region 970A adjacent to the central axis 999 of the exhaust passage and an outer region 970B distal to the central axis 999. In one example, the inner region 970A and the outer region 970B are concentric with respect to the central axis 999. The inner region includes a plurality of internal openings, while the outer region includes a plurality of external openings. The internal and external openings can be positioned to regulate the flow to either the inner region 970A or the outer region 970B. In one example, the external openings are misaligned and positioned to block flow to the outer region 970B, while the internal openings are aligned and positioned to facilitate exhaust flow only to the inner region 970A when the flow device 976 is in its first operating position. Alternatively, the external opening may be aligned and positioned to facilitate flow to the external region 970B, while the internal opening may be misaligned and positioned to block flow to the internal region 970A when the flow device 976 is in the second operating position.

[0087] The second emission control device 972 can be used with Figure 1The second catalytic converter device 8 similarly uses a selective catalytic reduction (SCR) catalytic converter. A temperature sensor 127 may be arranged between the first emission control device 970 and the second emission control device 972. An injector 982, fluidly coupled to a reductant reservoir, may be arranged between the first emission control device 970 and the second emission control device 972. The operation of the injector 982 may be based on feedback from the temperature sensor 127, as described above regarding... Figure 8 The method described in 800.

[0088] Vehicle system 906 may also include control system 914. Control system 914 is shown receiving information from a plurality of sensors 916 (various examples of which are described herein) and sending control signals to a plurality of actuators 981 (various examples of which are described herein). As an example, sensor 916 may include temperature sensor 128, pressure sensor 129, and exhaust gas sensor 126 located upstream of the emission control device. Other sensors, such as additional pressure, temperature, air / fuel ratio, and composition sensors, may be coupled to various locations within vehicle system 906. As another example, actuators may include throttle valve 962.

[0089] Controller 912 can be configured as a conventional microcomputer, including a microprocessor unit, input / output ports, read-only memory, random access memory, keep-alive memory, controller area network (CAN) bus, etc. Controller 812 can be configured as a powertrain control module (PCM). The controller can switch between sleep and wake-up modes to obtain additional energy efficiency. The controller can receive input data from various sensors, process the input data, and trigger actuators in response to the processed input data based on instructions or codes programmed therein corresponding to one or more routines. Controller 912 can be similar to... Figure 1 The control unit 7 is used.

[0090] In some examples, the hybrid vehicle 906 includes multiple torque sources available for one or more wheels 959. In other examples, the vehicle 906 is a conventional vehicle with only an engine, or an electric vehicle with only one or more electric motors. In the example shown, the vehicle 906 includes an engine 910 and an electric motor 951. The electric motor 951 may be a motor or a motor / generator. When one or more clutches 956 are engaged, the crankshaft of the engine 910 and the electric motor 951 may be connected to the wheels 959 via a transmission 954. In the example shown, a first clutch 956 is disposed between the crankshaft and the electric motor 951, and a second clutch 956 is disposed between the electric motor 951 and the transmission 954. A controller 912 may send signals to the actuators of each clutch 956 to engage or disengage the clutch, thereby connecting or disconnecting the crankshaft from the electric motor 951 and its connected components, and / or connecting or disconnecting the electric motor 951 from the transmission 954 and its connected components. The transmission 954 may be a gearbox, a planetary gear system, or another type of transmission. The powertrain can be configured in various ways, including parallel, series, or series-parallel hybrid vehicles.

[0091] The motor 951 receives power from the traction battery 961 to provide torque to the wheel 959. The motor 951 can also operate as a generator (e.g., during braking operations) to provide power to charge the battery 961.

[0092] Turn now Figure 10 The figure 1000 graphically illustrates a predictive engine operating sequence, showing the adjustment of the flow control device and injectors relative to one or more engine operating conditions. Curve 1010 shows the first exhaust temperature, and dashed line 1012 shows the first threshold temperature. Curve 1020 shows the exhaust volumetric flow rate, and dashed line 1022 shows the threshold. Curve 1030 shows the operating mode position of the flow control device. Curve 1040 shows the position of the exhaust flow. Curve 1050 shows the second exhaust temperature, and dashed line 1052 shows the second temperature threshold. Curve 1060 shows the reductant injection. As described above, the first exhaust temperature can be sensed via a first exhaust sensor disposed upstream of the first catalytic converter unit, and the second exhaust temperature can be sensed via a second exhaust sensor disposed between the first and second catalytic converter units. Time increases from left to right in the figure.

[0093] Before t1, the first exhaust temperature (curve 1010) is lower than the first threshold temperature (dashed line 1012). Thus, the flow device's operating mode (curve 1030) is in the first operating mode. The first operating mode aligns the internal opening of the flow device while simultaneously misaligning the external opening, allowing exhaust to flow only through the internal opening. In one example, the surface of the flow device's plate can block the external opening, which is misaligned to obstruct the exhaust flow through it. In this way, the exhaust flows along the central axis adjacent to the exhaust passage (e.g., Figure 9 The flow rate flows within the internal region of the flow device (central axis 999). In this way, the LNT of the first catalytic converter receives the exhaust gas without allowing it to flow into the oxidation catalyst of the LNT. A first operating mode is further selected based on the exhaust volumetric flow rate (curve 1020) being less than a threshold (dashed line 1022). The second exhaust temperature (curve 1050) is less than a second threshold temperature (dashed line 1052). Thus, the reductant injection is shut off. At t1, the first exhaust temperature, exhaust volumetric flow rate, and second exhaust temperature increase toward their respective thresholds.

[0094] Between t1 and t2, the exhaust volumetric flow rate increases to a level greater than a threshold. At t2, the operating mode switches from the first operating mode to the second operating mode. This causes the flow device plate to rotate at least partially in the second direction to adjust the alignment of the flow device opening. More specifically, by rotating to the second operating position, the external opening of the flow device can be aligned, while the internal opening of the flow device can be misaligned. This allows the external opening to be positioned so that exhaust gas flows into the outer region of the exhaust passage in the second operating position.

[0095] Between t2 and t3, the first and second exhaust temperatures continue to increase. The second exhaust temperature remains below the second threshold temperature, resulting in the reductant injection remaining off. The first exhaust temperature increases to a temperature above the first threshold temperature. Thus, even if the volumetric exhaust flow rate decreases to below the threshold value, the flow device will remain in the second operating position, and the exhaust will continue to flow only to the oxidation catalyst of the first catalytic converter and not to the LNT of the first catalytic converter.

[0096] At t3, the second exhaust temperature increases to a temperature greater than the second threshold temperature. This activates the reductant injection. After t3, reductant injection continues as the flow device remains in the second operating position. It should be understood that if the first exhaust temperature decreases to a temperature less than the first threshold temperature and the exhaust volumetric flow rate decreases to a value less than the threshold, the flow device can be adjusted to the first operating position.

[0097] In this manner, the flow control device can regulate the exhaust flow to the first catalytic converter in response to the exhaust temperature upstream of the first catalytic converter and / or the exhaust volumetric flow rate to the first catalytic converter. The first catalytic converter may include a first catalyst arranged in an internal radial region along a central axis adjacent to the exhaust passage. The first catalytic converter may also include a second catalyst concentric with and surrounding the first catalyst relative to the central axis. The flow device may include an internal opening and an external opening, the internal opening being shaped to allow exhaust to flow only to the first catalyst, and the external opening being shaped to allow exhaust to flow only to the second catalyst. The flow device may be rotatable to block one of the internal or external openings, such that only one of the first or second catalyst can receive exhaust. The technical effect of arranging the flow device upstream of the first catalytic converter to regulate the exhaust flow to different radial regions of the converter is to improve exhaust treatment efficiency. The second catalyst of the first catalytic converter may be configured to increase NO. x The ratio of nitrogen to nitrogen allows the second catalytic converter, downstream of the first catalytic converter which incorporates SCR properties, to more effectively treat nitrogen-containing compound emissions at a higher exhaust temperature relative to the first catalyst. This reduces emissions.

[0098] In another representation, an arrangement of an internal combustion engine having an exhaust system is provided, wherein at least one oxidation catalytic converter and at least one first nitrogen oxide storage catalytic converter are disposed in a common first catalytic converter device, wherein at least one first catalytic converter for selective catalytic reduction and at least one particulate filter are disposed downstream of the first catalytic converter device, and at least one delivery device for a reducing agent is disposed upstream of the catalytic converter for selective catalytic reduction, wherein the first catalytic converter device includes a first internal region and a second external region, and wherein a switching device for controlling exhaust flow is disposed at the upstream end, the switching device being implemented to allow exhaust to pass through the internal region in a first operating mode and to allow exhaust to pass through the external region in a second operating mode.

[0099] A first example of this arrangement also includes an oxidation catalytic converter located in the external region of the first catalytic converter device.

[0100] A second example, which optionally includes the arrangement of the first example, further includes a nitrogen oxide storage catalytic converter disposed in an internal region of the first catalytic converter device.

[0101] A third example of an arrangement including any of the above examples also includes a particulate filter and a catalytic converter for selective catalytic reduction disposed in a common second catalytic converter unit.

[0102] A fourth example of an arrangement including any of the above examples also includes an exhaust system in which a mixer for the fluid medium is disposed upstream of a catalytic converter for selective catalytic reduction.

[0103] A fifth example of an arrangement that includes any of the examples above also includes an oxidation catalytic converter optimized for high conversion efficiency from nitric oxide to nitrogen dioxide.

[0104] A hybrid electric vehicle having the arrangement described in any one of the preceding claims.

[0105] A method for controlling an exhaust aftertreatment having an arrangement as described in any one of the preceding claims includes: operating an internal combustion engine; determining a first exhaust temperature in a region upstream of a first catalytic converter device; switching a switching device to a first operating mode if the first exhaust temperature is less than or equal to a first threshold temperature, and entering a second operating mode if the first exhaust temperature is greater than the first threshold temperature; determining an exhaust velocity near the first catalytic converter device; leaving the switching device in the first operating mode if the velocity is less than or equal to a velocity threshold, and switching to the second operating mode if the velocity is greater than the threshold velocity.

[0106] A first example of the method further includes determining a second exhaust temperature near the catalytic converter used for selective catalytic reduction, and introducing a reducing agent into the exhaust system via a delivery device if the second exhaust temperature is greater than or equal to a second threshold temperature, and introducing no reducing agent into the exhaust system if the second exhaust temperature is less than the second threshold temperature.

[0107] A second example of the method, optionally including the first example, further includes the fact that when the switching device is switched to a second operating mode, the ratio of nitrogen dioxide to nitric oxide is expected to be 50%.

[0108] A third example of the method, which optionally includes any of the examples above, further includes a switching device that switches to a first operating mode or a second operating mode according to the operating point of the internal combustion engine.

[0109] A fourth example of the method, which optionally includes any of the examples above, further includes a switching device that switches to a first operating mode or a second operating mode based on a combination of different parameters in the sense of controlling the 3D mapping of the internal combustion engine.

[0110] One embodiment of the system includes a flow device shaped to allow exhaust gas to flow to an external or internal region of an emission control device. The flow device includes a rotatable first plate and a fixed second plate, each of the first and second plates including an internal opening and an external opening, wherein alignment of the internal and external openings is adjusted via rotation of the first plate. A first example of the system further includes a system in which, in a first operating position of the flow device, the external opening is misaligned and the internal opening is aligned, wherein the external opening is blocked to prevent exhaust gas flow therethrough. A second example of the system optionally including the first example further includes a system in which, in a second operating position of the flow device, the internal opening is misaligned and the external opening is aligned, wherein the internal opening is blocked to prevent exhaust gas flow therethrough. A third example of the system optionally including the first and / or second examples further includes a system in which the emission control device includes a dilute NO₂ fluidly coupled to the internal opening. x The trap and fluid are coupled to an externally opened oxidation catalyst, and dilute NO is contained therein. x The trap separates the catalyst from the oxidation catalyst fluid. A fourth example of the system, optionally including one or more of the first to third examples, further includes a system in which the oxidation catalyst is in dilute NO. x Radial outer side of the trap and around the dilute NO x The trap contains an oxidation catalyst and dilute NO. x The trap is concentric with respect to the central axis of the exhaust passage. A fifth example of the system, optionally including one or more of the first to fourth examples, further includes a temperature sensor and a volumetric flow sensor arranged upstream of the emission control device, wherein the flow device is adjusted in response to a comparison of the temperature sensed by the temperature sensor with a threshold temperature, and a comparison of the volumetric exhaust flow sensed by the volumetric flow sensor with respect to a threshold.

[0111] An embodiment of an engine system includes an engine fluidly coupled to an exhaust passage, a flow device arranged along the exhaust passage, the flow device including a first plate and a second plate, wherein one of the first plate or the second plate is rotatable between a first position and a second position, the first position aligning the internal openings of the first plate and the second plate and misaligning the external openings to allow exhaust gas to flow along the central axis of the exhaust passage, and the second position aligning the external openings of the first plate and the second plate and misaligning the internal openings to allow exhaust gas to flow away from the central axis of the exhaust passage, a catalytic converter device including an LNT arranged along an internal region of the catalytic converter device and an oxidation catalyst arranged along an external region of the catalytic converter device, wherein when the flow device is in the first position... The system includes an LNT receiving exhaust gas only when the flow device is in the second position, and an oxidation catalyst receiving exhaust gas only when the flow device is in the second position; a temperature sensor disposed upstream of the catalytic converter, configured to sense the temperature of the exhaust gas; a volume sensor disposed upstream of the catalytic converter, configured to sense the volumetric flow rate of the exhaust gas; and a controller having computer-readable instructions stored in its non-transitory memory, which, when executed, causes the controller to rotate one of the first or second plates to a first position in response to an exhaust gas temperature less than a threshold temperature and an exhaust gas volumetric flow rate less than a threshold, and to rotate one of the first or second plates to a second position in response to an exhaust gas temperature greater than or equal to a threshold temperature or an exhaust gas volumetric flow rate greater than or equal to a threshold. A first example of the engine system also includes a first plate having the same dimensions and shape as the second plate. A second example of the engine system optionally including the first example further includes a first plate comprising a plurality of internal openings and a plurality of external openings, the plurality of external openings being arranged radially outward of the plurality of internal openings, wherein the plurality of internal openings are spaced apart from each other via a radially inner surface of the first plate, and wherein the plurality of external openings are spaced apart from each other via a radially outer surface of the first plate. A third example of an engine system optionally including the first and / or second examples further includes a second plate comprising a plurality of internal second plate openings and a plurality of external second plate openings, the plurality of external second plate openings being arranged radially outward of the plurality of internal second plate openings, wherein the plurality of internal second plate openings are spaced apart from each other via a radially inner surface of the second plate, and wherein the plurality of external second plate openings are spaced apart from each other via a radially outer surface of the second plate. A fourth example of an engine system optionally including one or more of the first to third examples further includes a first position in which the plurality of internal first plate openings are aligned with the plurality of internal second plate openings, wherein the first position also includes a first plate opening misaligned with the plurality of external second plate openings, the plurality of external first plate openings being blocked by a radially outer surface of the second plate, and the plurality of external second plate openings being blocked by a radially outer surface of the first plate.A fifth example of an engine system optionally including one or more of the first to fourth examples further includes a plurality of external openings of the first plate aligned with a plurality of external openings of the second plate at a second location, wherein the second location also includes a plurality of internal openings of the first plate misaligned with a plurality of internal openings of the second plate, the plurality of internal openings of the first plate being blocked by a radially inner surface of the second plate, and the plurality of internal openings of the second plate being blocked by a radially inner surface of the first plate. A sixth example of an engine system optionally including one or more of the first to fifth examples further includes a first location including a LNT that allows exhaust gas to flow only to the catalytic converter and not to the oxidation catalyst of the catalytic converter, wherein the second location includes an oxidation catalyst that allows exhaust gas to flow only to the catalytic converter and not to the LNT of the catalytic converter. A seventh example of an engine system optionally including one or more of the first to sixth examples further includes a first catalytic converter arranged upstream of a second catalytic converter including a selective reduction catalyst relative to the direction of exhaust flow, and an injector positioned to directly inject into a portion of an exhaust passage between the first and second catalytic converters. An eighth example of an engine system that optionally includes one or more of the first to seventh examples further includes a first temperature sensor and a second temperature sensor disposed between a first catalytic converter and a second catalytic converter, wherein the temperature sensed by the first temperature sensor is compared with a first threshold temperature and the temperature sensed by the second temperature sensor is compared with a second threshold temperature, wherein the injector injects in response to the temperature sensed by the second temperature sensor being greater than the second threshold temperature.

[0112] An embodiment of a method includes: rotating a first plate of a flow device disposed upstream of a first catalytic converter unit relative to a fixed second plate to a first operating position in response to a first exhaust temperature being less than a first threshold temperature or a volumetric exhaust value being less than a threshold; rotating the first plate to a second operating position in response to a first exhaust temperature being greater than or equal to the first threshold temperature or a volumetric exhaust value being greater than or equal to the threshold; and injecting a reducing agent via an injector in response to a second exhaust temperature being greater than or equal to the second threshold temperature, the injector being positioned to inject into a portion of an exhaust passage downstream of the first catalytic converter unit and upstream of the second catalytic converter unit. A first example of the method further includes wherein the first operating position includes allowing exhaust gas to flow near a central axis of the exhaust passage, wherein the flow device, the first catalytic converter unit, and the second catalytic converter unit are disposed in the exhaust passage, and wherein allowing exhaust gas to flow near the central axis further includes allowing exhaust gas to flow only to the first catalytic converter unit with dilute NO. xA trap is used to collect exhaust gas without allowing it to flow to the oxidation catalyst of the first catalytic converter unit. A second example of the method, optionally including the first example, further includes a second operating position where the exhaust gas flows distal to the central axis of the exhaust passage, wherein flowing the exhaust gas distal to the central axis further includes allowing the exhaust gas to flow only to the oxidation catalyst without allowing it to flow to the dilute NO of the first catalytic converter unit. x A trap. A third example of the method, optionally including the first and / or second examples, further includes rotating the first plate relative to the second plate to a first operating position, comprising rotating the first plate in a first direction until an adapter of the first plate contacts a first end tab, and wherein the outer openings of the first and second plates are misaligned and sealed, and the inner openings are aligned and positioned to allow exhaust flow through them. A fourth example of the method, optionally including one or more of the first to third examples, further includes rotating the first plate relative to the second plate to a second operating position, comprising rotating the first plate in a second direction opposite to the first direction until an adapter of the first plate contacts a second end tab, and wherein the inner openings of the first and second plates are misaligned and sealed, while the outer openings are aligned and positioned to allow exhaust flow through them.

[0113] Note that the example control and estimation routines included herein can be used with various engine and / or vehicle system configurations. The control methods and routines disclosed herein can be stored as executable instructions in non-transitory memory and can be implemented by a control system comprising a combination of controllers and various sensors, actuators, and other engine hardware. The specific routines described herein can represent one or more of any number of processing strategies, such as event-driven, interrupt-driven, multitasking, multithreading, etc. Therefore, the various actions, operations, and / or functions shown can be performed in the sequence shown, in parallel, or in some omitted cases. Similarly, the processing order is not necessary 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 shown actions, operations, and / or functions can be repeatedly executed according to the specific strategy used. Furthermore, the described actions, operations, and / or functions can be graphically represented as code to be programmed into a non-transitory memory of a computer-readable storage medium in an engine control system, wherein the described actions are implemented by executing instructions in a system comprising a combination of various engine hardware components and electronic controllers.

[0114] It should be understood that the configurations and routines disclosed herein are exemplary in nature, and these specific embodiments are not to be considered limiting, as many variations are possible. For example, the above-described techniques can be applied to V-6, I-4, I-6, V-12, opposed 4-cylinder, and other engine types. The subject matter of this disclosure includes various systems and configurations, as well as all novel and non-obvious combinations and sub-combinations of other features, functions, and / or properties disclosed herein.

[0115] As used herein, unless otherwise specified, the term “approximately” shall be interpreted as indicating a range of plus or minus five percent.

[0116] The following claims specifically point to certain combinations and sub-combinations that are considered novel and non-obvious. These claims may refer to a "one" element or a "first" element or its equivalent. Such claims should be understood to include the incorporation of one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and sub-combinations of the disclosed features, functions, elements, and / or properties may be claimed by amending these claims or by setting new claims in this application or related applications. Such claims, whether broader, narrower, identical, or different in scope from the original claims, are considered to be included within the subject matter of this disclosure.

Claims

1. A system for exhaust aftertreatment, comprising: A flow device shaped to direct exhaust gas flow to an external or internal region of an exhaust control device, wherein the flow device includes a rotatable first plate and a fixed second plate, each of the first and second plates including an internal opening and an external opening, wherein the alignment of the internal and external openings is adjusted via rotation of the first plate. The emission control device includes a rare NOx trap arranged along the inner region and an oxidation catalyst arranged along the outer region. The rare NOx trap is fluidly coupled to the inner opening, and the oxidation catalyst is fluidly coupled to the outer opening. When the inner opening is aligned, only the rare NOx trap receives exhaust gas, and when the outer opening is aligned, only the oxidation catalyst receives exhaust gas.

2. The system of claim 1, wherein in the first operating position of the flow device, the outer opening is misaligned and the inner opening is aligned, wherein the outer opening is blocked to prevent exhaust flow through it.

3. The system of claim 2, wherein in the second operating position of the flow device, the internal opening is misaligned and the external opening is aligned, wherein the internal opening is blocked to prevent exhaust flow through it.

4. The system of claim 1, wherein the dilute NOx trap is fluidly separated from the oxidation catalyst.

5. The system of claim 4, wherein the oxidation catalyst is radially outside the lean NOx trap and surrounds the lean NOx trap, wherein the oxidation catalyst and the lean NOx trap are concentric about the central axis of the exhaust passage.

6. The system of claim 1 further includes a temperature sensor and a volumetric flow sensor disposed upstream of the emission control device, wherein the flow device is adjusted in response to a comparison of a temperature sensed by the temperature sensor with a threshold temperature and a comparison of a volumetric exhaust flow rate sensed by the volumetric flow sensor with respect to a threshold.

7. An engine system comprising: The engine is fluidly coupled to the exhaust passage; A flow device arranged along the exhaust passage includes a first plate and a second plate, wherein one of the first plate or the second plate is rotatable between a first position and a second position, the first position being aligned with the internal openings of the first plate and the second plate and not aligned with the external openings of the first plate and the second plate, so that exhaust flows along the central axis of the exhaust passage, and the second position being aligned with the external openings of the first plate and the second plate and not aligned with the internal openings of the first plate and the second plate, so that exhaust flows away from the central axis of the exhaust passage; A catalytic converter device includes a dilute NOx trap arranged along an internal region of the catalytic converter device and an oxidation catalyst arranged along an external region of the catalytic converter device, wherein when the flow device is in the first position, only the dilute NOx trap receives exhaust gas and when the flow device is in the second position, only the oxidation catalyst receives exhaust gas. A temperature sensor is disposed upstream of the catalytic converter unit and is configured to sense the temperature of the exhaust gas. A volume sensor is arranged upstream of the catalytic converter unit and is configured to sense the volumetric flow rate of the exhaust gas. as well as A controller having computer-readable instructions stored in non-transitory memory, which, when executed, cause the controller to: In response to the exhaust temperature being less than a threshold temperature and the exhaust volumetric flow rate being less than a threshold, one of the first plate or the second plate is rotated to the first position; as well as In response to the exhaust temperature being greater than or equal to the threshold temperature or the exhaust volumetric flow rate being greater than or equal to the threshold, one of the first plate or the second plate is rotated to the second position.

8. The engine system of claim 7, wherein the first plate has the same dimensions and shape as the second plate.

9. The engine system of claim 7, wherein the first plate includes a plurality of internal openings and a plurality of external openings, the plurality of external openings being arranged radially outward from the plurality of internal openings, wherein the plurality of internal openings are spaced apart from each other via a radially inner surface of the first plate, and wherein the plurality of external openings are spaced apart from each other via a radially outer surface of the first plate.

10. The engine system of claim 9, wherein the second plate includes a plurality of internal second plate openings and a plurality of external second plate openings, the plurality of external second plate openings being arranged radially outward from the plurality of internal second plate openings, wherein the plurality of internal second plate openings are spaced apart from each other via a radially inner surface of the second plate, and wherein the plurality of external second plate openings are spaced apart from each other via a radially outer surface of the second plate.

11. The engine system of claim 10, wherein the plurality of first plate internal openings are aligned with the plurality of second plate internal openings at the first position, wherein the first position further includes the plurality of first plate external openings not aligned with the plurality of second plate external openings, the plurality of first plate external openings being blocked by the radial outer surface of the second plate, and the plurality of second plate external openings being blocked by the radial outer surface of the first plate.

12. The engine system of claim 10, wherein in the second position the external openings of the plurality of first plates are aligned with the external openings of the plurality of second plates, wherein the second position further includes the internal openings of the plurality of first plates being misaligned with the internal openings of the plurality of second plates, the internal openings of the plurality of first plates being blocked by the radial inner surface of the second plates, and the internal openings of the plurality of second plates being blocked by the radial inner surface of the first plates.

13. The engine system of claim 7, wherein the first position includes allowing exhaust gas to flow only to the lean NOx trap of the catalytic converter device and not to the oxidation catalyst of the catalytic converter device, wherein the second position includes allowing exhaust gas to flow only to the oxidation catalyst of the catalytic converter device and not to the lean NOx trap of the catalytic converter device.

14. The engine system of claim 7, wherein the catalytic converter device is a first catalytic converter device arranged upstream of a second catalytic converter device including a selective reduction catalyst relative to the direction of the exhaust flow, and the engine system further includes an injector positioned to directly inject into a portion of the exhaust passage between the first catalytic converter device and the second catalytic converter device.

15. The engine system of claim 14, wherein the temperature sensor is a first temperature sensor, the engine system further comprising a second temperature sensor disposed between the first catalytic converter device and the second catalytic converter device, wherein the temperature sensed by the first temperature sensor is compared with a first threshold temperature and the temperature sensed by the second temperature sensor is compared with a second threshold temperature, wherein the injector injects in response to the temperature sensed by the second temperature sensor being greater than the second threshold temperature.

16. A method for exhaust aftertreatment, comprising: In response to the first exhaust temperature upstream of the first catalytic converter being less than a first threshold temperature and the volume exhaust value upstream of the first catalytic converter being less than a threshold, the first plate of the flow device arranged upstream of the first catalytic converter, relative to the fixed second plate, is rotated to a first working position. In response to the first exhaust temperature being greater than or equal to the first threshold temperature or the volumetric exhaust value being greater than or equal to the threshold, the first plate is rotated to a second working position; and In response to a second exhaust temperature between the first and second catalytic converter devices being greater than or equal to a second threshold temperature, a reducing agent is injected via an injector, the injector being positioned to inject into a portion of the exhaust passage downstream of the first catalytic converter device and upstream of the second catalytic converter device. In the first operating position, the exhaust gas flows only to the lean NOx trap of the first catalytic converter, and in the second operating position, the exhaust gas flows only to the oxidation catalyst of the first catalytic converter.

17. The method of claim 16, wherein the first operating position includes allowing exhaust gas to flow near the central axis of the exhaust passage, wherein the flow device, the first catalytic converter device, and the second catalytic converter device are arranged in the exhaust passage, and wherein allowing exhaust gas to flow near the central axis further includes allowing exhaust gas to flow only to the lean NOx trap and not to the oxidation catalyst.

18. The method of claim 17, wherein the second operating position further comprises allowing exhaust gas to flow distal to the central axis of the exhaust passage, wherein allowing exhaust gas to flow distal to the central axis further comprises allowing exhaust gas to flow only to the oxidation catalyst and not to the dilute NOx trap.

19. The method of claim 16, wherein rotating the first plate relative to the second plate to the first working position comprises rotating the first plate in a first direction until the adapter of the first plate contacts the first end tab, and wherein the external openings of the first plate and the second plate are misaligned and sealed, and the internal openings are aligned and positioned to allow exhaust flow through them.

20. The method of claim 19, wherein rotating the first plate relative to the second plate to the second working position comprises rotating the first plate in a second direction opposite to the first direction until the adapter of the first plate contacts the second end tab, and wherein the internal openings of the first plate and the second plate are misaligned and sealed, and the external openings are aligned and positioned to allow exhaust flow through them.

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