Exhaust mixer

Abstract

The present invention relates to exhaust mixers. Methods and systems for mixers are provided. In one example, a system can include a mixer disposed in a passageway, and the mixer is configured to mix two different gases upstream of a device.

Description

Technical Field

[0001] This invention generally relates to exhaust gas mixers. Background Technology

[0002] Higher engine loads and / or booster engine conditions result in higher combustion and exhaust temperatures. These higher temperatures increase nitrogen oxide (NOx) emissions. x Exhaust gases cause accelerated degradation of catalytic materials in the engine and exhaust system. Exhaust gas recirculation (EGR) is one way to combat these effects. The EGR strategy reduces the oxygen content in the intake air by diluting it with exhaust gas. When a diluted air / exhaust mixture replaces unmixed ambient air to support combustion in the engine, lower combustion and exhaust temperatures are observed. EGR can also increase fuel economy in gasoline engines by reducing throttling losses and heat dissipation.

[0003] Alternatively, when engine conditions are not suitable for EGR, a technology for engine exhaust aftertreatment employs selective catalytic reduction (SCR) to reduce NO in the exhaust. x A specific chemical reaction can occur between the ammonia and NO. Ammonia is introduced into the engine exhaust system upstream of the SCR catalyst by injecting a reducing agent into the exhaust passage. At high temperatures, the reducing agent entropy decomposes into NH3. SCR promotes the reaction of NH3 and NO. x The reaction between them, to convert NO x It is converted into nitrogen (N2) and water (H2O). However, some problems may arise during the injection of the reducing agent into the exhaust channel. In one example, the reducing agent may not mix well with the exhaust stream (e.g., the first part of the exhaust stream has a higher urea concentration than the second part), which may lead to poor SCR coating and emissions (e.g., NO). x The reaction between ) and SCR is poor.

[0004] Therefore, the mixing of exhaust gas with intake air, reducing agents, or itself is crucial for achieving optimal engine performance. Attempts to address insufficient exhaust gas mixing include arranging fluid mixers along the flow path to increase turbulence in the gases flowing through them.

[0005] However, the inventors have recognized the potential problems with such systems. For example, these mixers are often complex in design and difficult to integrate into engine systems of different shapes. For instance, the mixer may not be able to accommodate the various bends and / or injectors present in the channel. Furthermore, the molds and / or castings for these mixers are expensive, leading to increased production costs. Summary of the Invention

[0006] In one example, the above problems can be solved by an engine system including a mixing plate disposed between a first passage, a second passage, and an auxiliary passage, each of the above passages being coupled to a chamber, and wherein the plate is perforated and has an S-shaped cross-section, the plate dividing the chamber into two portions, with the first passage coupled to a first portion and the second passage coupled to a second portion. In this way, the gas in the first portion (and in one example all of the gas) is forced to flow through the plate before entering the second portion.

[0007] As one example, the auxiliary passage is coupled to the first portion. Gas from the first passage and the auxiliary passage can collide in the first portion before flowing through the perforations of the plate into the second portion. The plate can increase the turbulence, which can facilitate mixing between the gas from the first passage and the auxiliary passage. The mixed gas can flow through a segment of the second portion before flowing into the second passage. In this way, the mixed gas can improve the efficiency and performance of components disposed in the second passage downstream of the plate and chamber.

[0008] It is to be understood that the above overview is provided merely for purposes of summarizing some concepts of the disclosure and that the concluding statements made herein are not intended to determine the critical or essential characteristics of the claimed subject matter, the scope of which is defined by the appended claims. Furthermore, the claimed subject matter is not limited to implementing the embodiments described above or to the specific embodiments described hereinabove. Rather, the claimed subject matter can be practiced using any number of embodiments devised to achieve the same results. BRIEF DESCRIPTION OF DRAWINGS

[0009] Figure 1 is a schematic view of a single one of the cylinders in an engine including an exhaust mixer.

[0010] Figure 2A and Figure 2B illustrates a perspective view of a first example of an exhaust mixer.

[0011] Figure 3 illustrates a cross-sectional view of the first example of an exhaust mixer with an example exhaust flow therethrough.

[0012] Figure 4 illustrates a perspective view of a second example of an exhaust mixer.

[0013] Figure 5A illustrates a chamber in which the second example of an exhaust mixer is disposed.

[0014] Figure 5B illustrates a cross-sectional view of a chamber with the second example of an exhaust mixer.

[0015] Figure 6 illustrates a perspective view in which the exterior of the chamber is omitted, with an example exhaust flowing therethrough.

[0016] Figure 7A 、 Figure 7B 、 Figure 7C and Figure 7D Various locations of exhaust mixers in intake or exhaust systems are shown.

[0017] Figures 2A-6 approximately to scale. DETAILED DESCRIPTION

[0018] The following description relates to an exhaust mixer. The exhaust mixer can be disposed in an engine intake system and configured for mixing exhaust gas recirculation (EGR) and intake air. Additionally or alternatively, the exhaust mixer can be disposed in an engine exhaust system and configured for mixing exhaust gas and reductant injection. Figure 1 The engine shown in FIG. 1 includes at least one cylinder fluidly coupled to an intake system and an exhaust system. Each system optionally includes a mixer disposed therein.

[0019] In one example, the mixers disposed in the intake system and the exhaust system are substantially identical. However, the mixers can be shaped differently to accommodate different geometries of the intake system and the exhaust system. Figure 2A and Figure 2B A first example of a mixer is shown in FIG. 2. The mixer includes a circular plate physically coupled to a protrusion. Figure 3 An example of a first gas and a second gas flowing through the mixer is shown in FIG. 3.

[0020] Figure 4 A second example of a mixer is shown in FIG. 4. It shows the mixer disposed in a chamber that is coupled to a first passage, a second passage, and an auxiliary passage. The mixer can divide the chamber into two portions, where a first portion is coupled to the first passage and the auxiliary passage, and a second portion is coupled to the second passage. The mixer is curved and perforated. This will enable the mixer to flow gas from the first portion to the second portion in multiple radial directions.

[0021] Figure 5A An example of a first passage, a second passage, and an auxiliary passage coupled to a chamber is shown in FIG. 5. Figure 5B An upstream-to-downstream view of the internal structure of a chamber including a mixer is shown in FIG. 6. Figure 5B and Figure 6 Examples of gas flowing through a mixer and a chamber are shown in both FIG. 7 and FIG. 8.

[0022] Figures 7A-7D Various locations of a mixer relative to various components in an engine intake system and / or an engine exhaust system are shown.

[0023] Figures 1-7DAn example configuration with the relative positioning of multiple components is shown. If shown as directly contacting or directly connected to each other, then in at least one example, these elements may be referred to as directly contacting or directly connected, respectively. Similarly, in at least one example, elements shown as adjacent or adjacent to each other may be referred to as adjacent or adjacent to each other, respectively. As an example, components placed in coplanar contact with each other may be referred to as being in coplanar contact. As another example, in at least one example, elements positioned separately from each other with only space between them and no other components may be so referred to. As yet another example, elements shown as above / below each other, on opposite sides of each other, or to the left / right of each other may be so referred to relative to each other. Furthermore, as shown in the figures, in at least one example, the topmost element or the topmost point of an element may be referred to as the “top” of the component, while the bottommost element or the bottommost point of an element may be referred to as the “bottom” of the component. As used herein, top / bottom, above / below, above / below may be relative to the vertical axis of the figures and are used to describe the positioning of the elements in the figures relative to each other. Thus, in one example, an element shown above other elements is located vertically above said other elements. As yet another example, the shapes of the elements depicted in the accompanying drawings may be described as having those shapes (e.g., such as circular, straight, planar, curved, rounded, chamfered, angled, etc.). Furthermore, in at least one example, elements shown as intersecting each other may be described as intersecting elements or intersecting each other. Further still, in one example, an element shown inside or outside another element may be so referred to. It should be understood that one or more components cited as "substantially similar and / or identical" are distinguished from each other based on manufacturing tolerances (e.g., 1%–5% error).

[0024] Notice Figure 3 , Figure 5B and Figure 6 The arrows shown indicate where there is space for gas flow, and the solid lines of the device walls indicate locations where flow is blocked and where communication is impossible due to the lack of fluid connectivity created by the device walls crossing from one point to another. In addition to the openings in the walls that allow for such fluid connectivity, the walls create intervals between areas.

[0025] continue Figure 1which illustrates one cylinder in a multi-cylinder engine 10 in an engine system 100 that can be included in a propulsion system for an automobile. The engine 10 can be controlled at least in part by a control system including a controller 12 and 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 for generating a proportional pedal position signal. The combustion chamber 30 of the engine 10 can include a cylinder formed by a cylinder wall 32 in which a piston 36 is disposed. The piston 36 can be coupled to a crankshaft 40 to convert the reciprocating motion of the piston to rotational motion of the crankshaft. The crankshaft 40 can be coupled to at least one drive wheel of the vehicle 5 through an intermediate transmission system. Additionally, a starter motor can be coupled to the crankshaft 40 through a flywheel to enable starting operation of the engine 10.

[0026] The combustion chamber 30 can receive intake air from an intake manifold 44 through an intake passage 42 and can expel combustion gases through an exhaust passage 48. The intake manifold 44 and the exhaust passage 48 can be selectively in communication with the combustion chamber 30 through an intake valve 52 and an exhaust valve 54, respectively. In some examples, the combustion chamber 30 can include two or more intake valves and / or two or more exhaust valves.

[0027] In this example, the intake valve 52 and the exhaust valve 54 can be controlled by cam drive via respective cam drive systems 51 and 53. The cam drive systems 51 and 53 can each include one or more cams and can utilize one or more of a cam profile switching system (CPS), a variable cam timing system (VCT), a variable valve timing system (VVL), and / or a variable valve lift system (VVL) operated by the controller 12 to vary the operation of the valves. The positions of the intake and exhaust valves 52 and 54 can be determined by position sensors 55 and 57, respectively. In alternative examples, the intake valve 52 and / or the exhaust valve 54 can be controlled by a solenoid actuated valve drive. For example, the cylinder 30 can alternatively include an intake valve controlled by a solenoid actuated valve drive and an exhaust valve controlled by cam drive via a cam drive including a CPS and / or VCT system.

[0028] A fuel injector 69 is shown coupled directly to the combustion chamber 30 to inject fuel into the combustion chamber in proportion to a pulse width of a signal received from the controller 12. In this manner, the fuel injector 69 provides so-called direct injection of fuel into the combustion chamber 30. For example, the fuel injector 69 can be mounted to a side of the combustion chamber or above the combustion chamber. Fuel can be delivered to the fuel injector 69 by a fuel system (not shown) including a fuel tank, a fuel pump, and a fuel rail. In some examples, alternatively or additionally, the combustion chamber 30 can include a fuel injector disposed in the intake manifold 44 in a configuration for providing so-called port injection of fuel to an intake port upstream of the combustion chamber 30.

[0029] A spark plug 66 is utilized to provide a spark to the combustion chamber 30. The ignition system can further include an ignition coil (not shown) for boosting the voltage supplied to the spark plug 66. In other examples, such as in diesel engines, there can be no spark plug 66.

[0030] The intake passage 42 can include a throttle valve 62 having a throttle plate 64. In this particular example, the position of the throttle plate 64 can be varied by the controller 12 by signals provided to an electric motor or actuator included in the throttle valve 62, such a configuration is commonly referred to as electronic throttle control (ETC). In this manner, the throttle valve 62 can be operated to vary the intake provided to the combustion chamber 30 and other engine cylinders. The position of the throttle plate 64 can be provided to the controller 12 by a throttle position signal. The intake passage 42 can include a mass air flow sensor 120 and a manifold air pressure sensor 122 for sensing the amount of air entering the engine 10.

[0031] An exhaust sensor 126 is shown coupled to the exhaust passage 48 upstream of the emission control device 70 according to the exhaust flow direction. The sensor 126 can be any suitable sensor for providing an indication of the exhaust air-fuel ratio, such as a linear oxygen sensor or UEGO (universal or wide range exhaust gas oxygen sensor), a dual bed oxygen sensor or EGO, a HEGO (heated EGO), a NO x , HC, or CO sensor, etc. In one example, the upstream exhaust sensor 126 is a UEGO configured to provide an output, such as a voltage signal, proportional to the amount of oxygen present in the exhaust. The controller 12 converts the oxygen sensor output to an exhaust air-fuel ratio through an oxygen sensor transfer function.

[0032] The emission control device 70 is shown disposed along the exhaust passage 48 upstream of the exhaust sensor 126. The device 70 can be a three-way catalyst (TWC), a particulate filter, a diesel oxidation catalyst, a NO xThe trap, various other emission control devices, or combinations thereof. In some examples, the emission control device 70 can be periodically reset by operating at least one cylinder of the engine within a particular air-to-fuel ratio during operation of the engine 10.

[0033] A selective catalytic reduction (SCR) device 72 is shown disposed along the exhaust passage 48 downstream of the emission control device 70. In some examples, the emission control device 70 can be omitted and only the SCR device 72 positioned downstream of the exhaust sensor 126. In other examples, the SCR device 72 can be upstream of the emission control device 70. An injector (not shown) can be disposed upstream of the SCR device 72. The injector can be positioned to inject a reductant into the exhaust passage 48. A reservoir can store the reductant. The reductant includes fuel, urea, etc. The controller 12 can signal the actuator.

[0034] An exhaust gas recirculation (EGR) system 140 can deliver a desired portion of exhaust from a portion of the exhaust passage 48 upstream of the emission control device 70 to the intake manifold 44 via an EGR passage 152. The amount of EGR provided to the intake manifold 44 can be varied by the controller 12 through an EGR valve 144. In some cases, the EGR system 140 can be used to adjust the temperature of the air-fuel mixture within the combustion chamber, thus providing a method of controlling the timing of ignition in some combustion modes.

[0035] A first mixer 71 A is disposed at an intersection between the intake manifold 44 and the EGR passage 152 downstream of the throttle 62. The first mixer 71 A can be configured to facilitate mixing between exhaust gas and intake air upstream of the cylinders 30. A second mixer 71 B is disposed between the emission control device 70 and the SCR device 72. The second mixing device 71 B can be configured to mix exhaust gas from various portions of the exhaust passage (e.g., an outer radial portion can mix with an inner radial portion). In one example, the first mixer 71 A and the second mixer 71 B are the same. Additionally or alternatively, the first mixer 71 A and the second mixer 71 B are different mixers. It should be appreciated, however, that the locations of the first mixer 71 A and the second mixer 71 B are exemplary and other locations are contemplated herein, as demonstrated below. Figures 7A-7D

[0036] ​The first and second mixers 71A and 71B can comprise a chemically inert material to prevent chemical reactions between the components in the gas stream and the components of the surface of the mixer. Additionally or alternatively, the first and second mixers 71A and 71B can be composed of one or more of carbon fiber, magnesium, aluminum, steel, titanium, plastic, alloys, and the like. The first and second mixers 71A and 71B can also comprise a coating configured to make the surface of the mixer non-stick. Such a coating can comprise one or more of ceramic, silicon dioxide, Teflon, and the like. The first and second mixers 71A and 71B can be arranged in a straight or curved portion of the channel without departing from the scope of the present disclosure.

[0037] The controller 12 is shown in Figure 1 FIG. 1 as a microcomputer including a microprocessor unit (CPU) 102, input / output ports (I / O) 104, an electronic storage medium for executable programs and calibration values, shown in this particular example as a read only memory (ROM) 106 (e.g., non-transitory memory), a random access memory (RAM) 108, a keep alive memory (KAM) 110, and a data bus. The controller 12 can receive various signals from sensors coupled to the engine 10, including, in addition to those described above, a measurement of intake mass air flow (MAF) from a mass air flow sensor 120, an engine coolant temperature (ECT) from a temperature sensor 112 coupled to a cooling jacket 114, an engine position signal from a Hall effect sensor 118 (or other type) that senses the position of the crankshaft 40, a throttle position from a throttle position sensor 65, and a manifold absolute pressure (MAP) signal from a sensor 122. An engine speed signal can be generated by the controller 12 from the crankshaft position sensor 118. The manifold pressure signal also provides an indication of the vacuum or pressure in the intake manifold 44. It is noted that various combinations of the above-described sensors can be used, such as a MAF sensor without a MAP sensor, or vice versa. During engine operation, engine torque can be inferred from the output of the MAP sensor 122 and the engine speed. In addition, such sensors, along with the sensed engine speed, can serve as a basis for estimating the charge (including air) introduced into the cylinders. In one example, the crankshaft position sensor 118 (which also serves as an engine speed sensor) can generate a predetermined number of equally spaced pulses per crankshaft revolution.

[0038] The storage medium read only memory 106 can be programmed with computer readable data representing non-transitory instructions executable by the processor 102 for performing the methods described below and other variants as contemplated but not specifically listed. The controller 12 receives signals from various sensors in Figure 1 the engine 10 and, using the received signals and instructions stored on the controller's memory, utilizesFigure 1 Various actuators in the system 100 are used to adjust the operation of the engine.

[0039] In some examples, the vehicle 5 can be a hybrid vehicle in which multiple sources of torque are available to one or more wheels 25. In other examples, the vehicle 5 is a conventional vehicle with only an engine, or an electric vehicle with only electric machine(s). In the example shown, the vehicle 5 includes an engine 10 and an electric machine 22. The electric machine 22 can be a motor or a motor / generator. When one or more clutches 26 are engaged, the crankshaft 40 of the engine 10 and the electric machine 22 are connected to the wheels 25 through a transmission 24. In the example shown, a first clutch 26 is located between the crankshaft 40 and the electric machine 22, and a second clutch 26 is located between the electric machine 22 and the transmission 24. The controller 12 can send a signal to an actuator of each clutch 26 to cause the clutch to engage or disengage, to connect or disconnect the crankshaft 40 from the electric machine 22 and other components connected thereto, and / or to connect or disconnect the electric machine 22 from the transmission 24 and other components connected thereto. The transmission can be a gear box, a planetary gear system, or another type of transmission. The powertrain can be configured in different ways, such as a parallel, series, or series-parallel hybrid vehicle.

[0040] The electric machine 22 receives electrical energy from the traction battery 28 to provide torque to the wheels 25. The electric machine 22 can also act as a generator to charge the battery 28, for example during braking operations.

[0041] Turning now to Figures 2A-2B , they show the same perspective view of the mixer 210. However, in Figure 2A , the protrusions 220 are transparent to visualize the plate 230. Thus, in Figure 2B , the protrusions 220 are not transparent and the plate 230 is blocked by the protrusions 220. Figures 2A-2B The descriptions are made in this order.

[0042] The axis system 290 includes three axes, an x-axis parallel to the horizontal direction (arrow 280), a y-axis parallel to the vertical direction, and a z-axis perpendicular to both the x-axis and the y-axis. The direction of the gas flow is generally parallel to the arrow 280. Here, the arrow 280 is interchangeably referred to as the direction 280 of the gas flow or the horizontal direction 280. The arrow 281 shows the gravity (here, the gravity 281).

[0043] A mixer 210 can be disposed in the passage 202. The passage 202 can be tubular. In one example, the mixer 210 is physically coupled to an inner surface of the passage 202 along an outer perimeter of the plate 230. The coupling element between the mixer 210 and the inner surface of the passage 202 can include one or more of a weld, a screw, a fusion, an adhesive, etc. Gas can not flow between the inner surface of the passage 202 and the outer perimeter of the mixer 210. Accordingly, the plate 230 includes a diameter that corresponds to a diameter of the passage 202 such that gas in the passage 202 is forced to flow through the plate 230 before reaching its intended area. The mixer 210 can be used similarly to one or more of the first mixer 71A and the second mixer 71B in Figure 1 . Likewise, the passage 202 can be similar to the intake passage 42 and / or the intake manifold 44 or the exhaust passage 48 in Figure 1 . Accordingly, the gas flow 280 can represent an exhaust flow or an intake flow depending on the location of the mixer 210.

[0044] The mixer 210 is fixedly coupled to the passage 202 such that it is not movable. Accordingly, the mixer 210 does not slide, rotate, or actuate. Furthermore, the mixer 210 is not powered by mechanical, hydraulic, pneumatic, or electrical means.

[0045] In one example, if the passage 202 is an intake passage and the mixer 210 is an EGR mixer, then the arrows represent the direction of the intake gas flow. The mixer can receive an exhaust gas recirculation (EGR) flow in a direction that is transverse to the direction of the intake gas flow or in a direction that is just opposite to the direction of the intake gas flow.

[0046] The mixer 210 includes the protrusion 220 and the plate 230, the mixer 210 can be similar to a bowl with a flat bottom (as in a dog bowl). Additionally or alternatively, the mixer 210 can be similar to a torus and / or a half-longitudinally cut donut with a bevel and an opening omitted along its center. The mixer is symmetrical to the central axis 284.

[0047] The plate 230 is substantially parallel to the y-z plane. Thus, the plate 230 is generally flat. The surface of the plate 230 is impermeable to gas flow. Gas colliding with the surface of the plate 230 bounces off the surface without flowing through it. The plate 230 includes a plurality of perforations 232 disposed on its surface, the plurality of perforations 232 configured to allow gas to pass through the plate 230. The perforations 232 are symmetrically distributed on the plate 230 about the vertical axis 282 and / or the central axis 284. However, it should be appreciated that the perforations 232 can be asymmetrically distributed on the plate 230 without departing from the scope of the present disclosure. In this manner, the perforations 232 are the only portions of the plate 230 through which gas can flow. In other words, gas flowing in the channel 202 from an upstream to a downstream direction relative to the plate 230 can only reach a portion of the channel 202 downstream of the plate 230 by flowing through one or more perforations on the plate 230. Thus, the plate 230 can be a uniform, continuous plate having perforations disposed thereon.

[0048] In one example, each of the perforations 232 is elliptical and similar in size. However, it should be appreciated that each of the perforations 232 can not all be elliptical and different from one another in shape. For example, one or more of the perforations 232 can be triangular, square, rectangular, circular, pentagonal, hexagonal, and other shapes without departing from the scope of the present disclosure.

[0049] The plate 230 is physically coupled to the protrusion 220 along its outer perimeter. In other words, the portion of the plate 230 coupled to the inner surface of the channel 202 can also be coupled to the protrusion 220. The manner of coupling between the plate 230 and the protrusion 220 can include one or more of welding, fusing, gluing, screws, and the like.

[0050] The tip 222 of the protrusion 220 corresponds to the portion of the protrusion 220 furthest from the plate 230. The outer surface 224 of the protrusion 220 extends from the outer perimeter of the plate 230 towards the tip 222. As shown, the outer surface 224 is angled with respect to the surface of the plate 230. In one example, the angle formed between the plate 230 and the outer surface 224 is between 60°-80°. Further, the inner surface 226 of the protrusion 220 extends from the center of the plate 230 towards the tip 222. The inner surface 226 can be similarly angled with respect to the plate 220 as the outer surface 224. The inner surface 226 and the outer surface 224 intersect and are physically coupled at the tip 222.

[0051] The cross-section of the outer surface 224 taken along the y-z plane can be substantially circular. The diameter of the cross-section of the outer surface 224 decreases along the x-axis from the plate 230 toward the tip 222. Likewise, the cross-section of the inner surface 226 taken along the y-z plane is also substantially circular. The diameter of the cross-section of the inner surface 226 increases along the x-axis from the plate 230 toward the tip 222. In this manner, the cross-sections of the outer surface 224 and the inner surface 226 approach each other until they are the same size at the tip 222.

[0052] The outer surface 224 also includes outer perforations 225. Likewise, the inner surface 226 includes inner perforations 227. The outer perforations 225 and the inner perforations 227 are substantially the same. Alternatively, the outer perforations 225 and the inner perforations 227 can be different. The shape of the outer perforations 225 and the inner perforations 227 can include one or more of triangular, circular, elliptical, square, rectangular, pentagonal, etc. The surface of the protrusion 220 is impermeable to gas flow. Thus, the outer perforations 225 and the inner perforations 227 can allow gas to pass through the protrusion 220. There is a space between the plate 230, the outer surface 224, and the inner surface 226 for exhaust gas to enter and flow through. The perforations 232, the outer perforations 225, and the inner perforations 227 can fluidly couple this space with the passage 202.

[0053] Turning now to Figure 3 which illustrates an embodiment 300 of a cross-section of the mixer 210 according to the cut plane A-A. Thus, components appearing previously can be similarly numbered in the subsequent figures. An example gas flow through the mixer 210 is illustrated. The solid arrows 312 can represent a first gas, and the dashed arrows can represent a second gas different from the first gas. As shown, the cross-section of the mixer 210 taken along the x-axis includes a triangle that is the same size as the triangle angles distributed on either side of the central axis 284.

[0054] In the embodiment 300, the mixer 210 can be described as an EGR mixer disposed in an intake passage (e.g., the intake passage 42 in Figure 1 ) with an inlet passage 302 and an outlet passage 304. The outlet passage 304 is downstream of the mixer 210 relative to the usual flow direction of intake gas flow in the inlet passage 302 (shown by the arrows 399). The outlet passage 304 is perpendicular to the inlet passage 302 and an EGR passage 306 (e.g., the EGR passage 152 in Figure 1 ). The tip 222 of the mixer 210 is physically coupled to the EGR passage 306 so that EGR can flow directly to the inner surface 226. Thus, the solid arrows 312 depict many example intake gas flows through the mixer 210. The dashed arrows 314 depict many example EGR flows through the mixer 210.

[0055] It should be appreciated that in some embodiments, the orientation of the outlet passage 304 and the orientation of the EGR passage 306 can be reversed without departing from the scope of the present disclosure. That is, the EGR passage 306 can be perpendicular to the inlet passage 302, and the outlet passage 304 can be parallel to the inlet passage 302. The outlet passage 304 can be physically coupled to the top end 222 of the mixer 210, similar to the EGR passage 306 in the embodiment 300. Likewise, in this example, the diameter of the outlet passage 304 is smaller than the diameter of the inlet passage.

[0056] In another embodiment, the mixer 210 can be disposed in an exhaust passage. A reductant injector can be positioned in the exhaust passage to inject reductant toward or adjacent the mixer. The injector can be positioned at a plurality of angles relative to a central axis of the mixer. In this manner, the mixer 210 can be further configured to mix only exhaust gas or exhaust gas and reductant. In this example, the passage 306 can correspond to a passage for introducing reductant into the exhaust gas. The passages 302 and 304 can represent upstream and downstream portions, respectively, of an exhaust passage that are separated by the mixer 210.

[0057] The inlet passage 302 can direct intake gas 312 toward the plate 230 of the mixer 210. The diameter of the plate 230 is equivalent to the diameter of the inlet passage 302. Thus, the intake gas stream 312 can flow through the mixer 210 before flowing to the outlet passage 304. In this example, all of the intake gas 312 in the intake passage flows through the mixer 210 before flowing to the outlet passage 304. As illustrated, the intake gas 312 flows through the perforations 232 and into the space 320 of the mixer 210. In the space 320, the intake gas 312 can flow in a plurality of directions. These directions can include radially outward toward the inner surface of the passage 302, radially inward toward the central axis, and / or longitudinally along the central axis 284. The intake gas 312 can flow through the outer perforations 225 of the outer surface 224, through the inner perforations 227 of the inner surface 226, or through both. In one example, the intake gas 312 is forced to flow through at least the perforations 232 of the plate and the outer perforations 225 of the outer surface 224 before reaching the outlet passage 304. By doing so, the turbulence in the intake gas 312 is increased, thereby increasing the chaotic and unpredictable nature of the flow direction of the intake gas 312. Figure 3

[0058] Specifically, the outer perforations 225 can direct the first gas 312 to flow toward the inner surface of the inlet passage 302. In contrast, the inner perforations 227 can direct the first gas 312 to flow toward the central axis 284. This perturbation can result in an increased number of collisions between gases from different radial portions of the inlet passage 302 before the gases reach the outlet passage 304.

[0059] ​EGR passage 306 can direct EGR gas toward tip 222 and / or inner surface 226 of mixer 210. The diameter of EGR passage 306 is comparable to the diameter of tip 222 so that EGR flow can flow through mixer 210 before flowing to outlet passage 304. In Figure 3 In the example of FIG. 3, all EGR 314 flows through mixer 210 before flowing to outlet passage 304. As illustrated, EGR 314 flows through inner perforations 227 of inner surface 226 and into space 320. In space 320, EGR 314 can flow in multiple directions. EGR 314 can flow through outer perforations 225, through perforations 232 of plate 230, or both. Additionally or alternatively, EGR 314 collides with intake gas 312 as soon as it exits EGR passage 306. The collision occurs in space 320 or other portions of intake passage 302 and / or mixer 210 upstream of outlet passage 304. In this way, the uniformity of intake gas and EGR is increased relative to an intake passage that does not include mixer 210. By increasing the mixing of EGR with intake gas, the distribution of EGR among each cylinder of an engine is more even, providing excellent combustion stability, reduced emissions, and fuel economy.

[0060] Specifically, before EGR 314 flows into outlet passage 304, it flows through inner perforations 227, through outer perforations 225, and then into outlet passage 304. Thus, any gas (e.g., intake gas 312 or EGR 314) is forced to flow through outer perforations 225 before flowing to outlet passage 304. By forcing gas to flow through mixer 210 before reaching outlet passage 304, the mixing of the gas can be promoted.

[0061] Turning now to Figure 4 illustrates an embodiment 400 of a mixer 410 arranged in passage 402. Mixer 410 can be used similarly to first mixer 71 A or second mixer 71 B. Thus, mixer 410 can be configured for mixing intake gas and EGR, or for increasing the uniformity of exhaust gas with or without reductant. Shaft system 490 is similar to shaft system 290 included in Figures 2A-2B

[0062] Mixer 410 is physically coupled to the inner surface of passage 402 by one or more of welding, fusing, screws, adhesives, etc. Mixer 410 is fixedly coupled to passage 402. In one example, mixer 410 cannot slide, rotate, swing, or otherwise move. As such, mixer 410 is fixed and immovable.

[0063] ​The mixer 410 can be curved about its vertical axis 482 and central axis 484. In one example, the surface of the mixer 410 is approximately S-shaped. However, it should be understood that the waveform period of the surface of the mixer 410 can be shortened to form multiple waveforms of the mixer. For example, in Figure 4 In embodiment 400, a single waveform cycle of the mixer surface is shown, comprising two vertices 412 and 414 pointing in opposite directions. Similarly, multiple iterations of the two vertices 412 and 414 can be included in other embodiments of the mixer without departing from the scope of this disclosure. For example, there can be a total number of vertices 412 and 414 such as 4, 6, 8, 10, etc. In one example, the number of vertices is even such that the number of vertices 412 and 414 are equal. In other examples, the total number of vertices is odd such that the number of vertices 412 and 414 are not equal.

[0064] A portion of channel 402 may be divided and / or separated by mixer 410. Gases between the two portions may mix after flowing through one or more perforations 416. Perforations 416 extend along the entire surface of mixer 410 and may be the only portion through which gas can flow in mixer 410. Mixer 410 may divide channel 402 into unequal portions, with the first portion being larger than the second. In this way, mixer 410 is slightly shorter than the diameter of channel 402 but still physically connected to the inner surface of channel 402. In one example, the height of mixer 410 is equal to the diameter of channel 402 to divide channel 402 in half.

[0065] Each perforation 416 is approximately identical in size and shape. Perforations 416 can be circular, elliptical, triangular, rectangular, pentagonal, trapezoidal, square, rhomboid, etc. Perforations 416 may not be aligned with the vertical axis 482. Alternatively, perforations 416 may be aligned about the vertical axis 482, with the space between each perforation being approximately uniform. Perforations 416 are transverse to the general direction of gas flow (arrow 499). In one example, perforations 416 are perpendicular to the direction of gas flow. Perforations 416 follow the surface of mixer 410 so that the orientation of perforations 416 in adjacent rows differs. However, the orientation of perforations 416 in a shared row is generally similar. A row may contain a series of adjacent perforations parallel to the direction of gas flow. Therefore, perforations in a row share a similar vertical height. In this way, perforations arranged at different heights are not in the same row.

[0066] In some examples, the shape and size of the perforations 416 in different rows can be different. For example, the perforations in the first row and the perforations in the second row can be different.

[0067] Now go toFigure 5A which illustrates an embodiment 500 of a chamber 502 that houses a mixer (e.g., Figure 4 the mixer 410 in Figure 4 may be used similarly to the passage 402 in The chamber 502 can be cylindrical, as illustrated in the figures, but other suitable shapes are contemplated herein. For example, the chamber 502 can be a cube, a cuboid, a sphere, and other three-dimensional shapes.

[0068] The first passage 512 is fluidly coupled to an upstream end 504 of the chamber 502. The second passage 514 is fluidly coupled to a downstream end 506 of the chamber 502. The upstream end 504 and the downstream end 506 of the chamber 502 are disposed on opposite sides of the tubular wall 508 of the chamber 502. The upstream end 504 and the downstream end 506 are physically coupled to the tubular wall 508 by welding, fusing, screws, adhesives, or other means. The upstream end 504, the downstream end 506, and the tubular wall 508 are impermeable to the exhaust stream. Thus, the chamber 502 does not include any other inlet or additional outlet besides the first passage 512 and the second passage 514. In this way, gas cannot flow directly through the upstream end 504, the downstream end 506, or the tubular wall 508 to the ambient air or the engine.

[0069] The diameter of the chamber 502 is greater than the diameter of the first passage 512 and the second passage 514. The first passage 512 and the second passage 514 can be radially misaligned with respect to each other about the central axis 584. In addition, the first passage 512 and the second passage 514 can be misaligned with respect to each other in a vertical direction. In the illustrated example, the first passage 512 is slightly lower than the second passage 514.

[0070] The auxiliary passage 516 is coupled to the chamber 502 at a slightly higher region of the chamber 502 relative to the location of the first passage 512 and the second passage 514. An adapter 518 can be disposed between the auxiliary passage 516 and the tubular wall 508. The adapter 518 can be configured to disperse and / or diffuse the gas stream from the auxiliary passage 516 into the chamber 502. The auxiliary passage 516 can be offset to one side of the chamber 502, as illustrated in Figure 5B .

[0071] Turning now to Figure 5Bwhich illustrates an embodiment 550 of the interior of the chamber 502. In particular, it illustrates a view from upstream to downstream of the chamber 502 omitting the upstream end 504 and the downstream end 506. The interior of the chamber 502 houses the mixer 410. The mixer 410 divides the interior of the chamber 502 into a first portion 552 and a second portion 554. The first portion 552 is directly fluidly coupled with the first passage 512 and the auxiliary passage 516 due to the misalignment of the first passage 512 and the second passage 514 in the vertical direction and the radial direction. The second portion 554 is directly fluidly coupled with the second passage 514. The auxiliary passage 516 is positioned to first direct the gas along the curved surface of the mixer 410 before flowing through the mixer 410 to the second portion 554 or through the remainder of the first portion 552. The auxiliary passage 516 can direct the gas into the chamber 502 in a direction transverse to the direction of the gas flow from the first passage 512 into the chamber 502. In one example, the direction of the gas exiting the auxiliary passage 516 and entering the chamber 502 is perpendicular to the direction of the gas exiting the first passage 512 and entering the chamber 502.

[0072] The solid arrows 562 represent a first gas flow, and the dashed arrows 564 represent a second gas flow. In one example, the solid arrows 562 represent intake gas, and the dashed arrows 564 represent EGR. In another example, the solid arrows 562 represent exhaust gas, and the dashed arrows 564 represent gaseous reductant. It should be recognized, however, that the dashed arrows 564 can represent liquid reductant without departing from the scope of the present disclosure. Thus, the auxiliary passage 516 can be fluidly coupled with an EGR passage or a reductant injector outlet. As shown, the arrows 562 and 564 can flow through the volume of the first portion 552 of the chamber 502 before flowing through the perforations (e.g., the perforations 416) of the mixer 410 and into the second portion 554. The second passage 514 can receive the first gas flow 562 and the second gas flow 564 from the second portion 554. In one example, the second passage 514 is fluidly coupled with the first portion 552 and the second portion 554. In another example, the second passage 514 is fluidly coupled with the second portion 554. Figure 6 Another example of gas flow through a chamber containing a mixer 410 is illustrated in FIG. 5B.

[0073] Turning now to Figure 6embodiment 600 that illustrates a surface of the second portion 554 being omitted to illustrate gas flowing through the mixer from the first portion 552 to the second portion 554. The first gas (solid arrow 562) flows from the first passage 512 into the first portion 552. As such, the first passage 512 functions as an inlet passage. The first gas can flow through a volume of the first portion 552 that is located between the mixer 410 and a corresponding surface of the tubular wall 508. The first portion 552 can further receive the second gas (dashed arrow 564) that also flows through the first portion 552. The first gas and the second gas mix in the first portion 552 before flowing into the second portion 554. Additionally or alternatively, the first gas and the second gas can flow through the mixer 410 and to the second portion 554 without mixing in the first portion 552.

[0074] The perforations 416 of the mixer 410 can impart different directionality to the first gas stream and the second gas stream depending on where the first gas stream and the second gas stream flow through the mixer 410. This can be determined by the curvature of the mixer 410. In other words, different rows of perforations 416 can direct the first gas and the second gas in different angular directions. The perforations 416 can direct the first gas stream and the second gas stream in different radial directions toward a surface of the tubular wall 508 that corresponds to the second portion 554. As a result, the degree of turbulence is increased, which can further promote mixing of the first gas and the second gas before the first gas and the second gas flow out of the second portion 554 of the chamber 502 and into the second passage 514.

[0075] Turning now to Figures 7A-7D various embodiments of intake and exhaust systems that include a mixer are illustrated. Figures 7A-7D The mixer illustrated in Figure 1 the first mixer 71 A and / or the second mixer 71 B illustrated in Figures 2A-2B the mixer 210 illustrated in Figure 4 the mixer 410 illustrated in

[0076] Turning now to Figure 7A embodiment 700 that illustrates a mixer 702 arranged at a junction between an EGR outlet 704 and an intake passage 706 upstream of an engine 708. The mixer can mix exhaust gas and intake air upstream of the engine 708. It should be appreciated, however, that the mixer 702 can be arranged downstream of the junction and upstream of the engine 708 without departing from the scope of the present disclosure.

[0077] Turning now to Figure 7Bwhich shows an embodiment 720 of a mixer 722 arranged in an exhaust passage 724, which contains an aftertreatment device 726 arranged downstream of the mixer 722. In one example, the aftertreatment device 726 is an SCR device. The exhaust passage 724 can further contain a reductant injector arranged at a first location, such as the reductant injector 728A shown. Alternatively, the exhaust passage 724 can contain a reductant injector arranged at a second location, such as the reductant injector 728B shown. The reductant injector 728A is positioned for injecting reductant into a portion of the exhaust passage 724 upstream of the mixer 722. Conversely, the reductant injector 728B is positioned for injecting reductant into a portion of the exhaust passage 724 corresponding to the location of the mixer 722. The reductant injected can be liquid or gaseous. Regardless, the mixer 722 can be configured to facilitate mixing between the injected reductant and the exhaust gas. By facilitating dispersion and uniformity of the reductant in the exhaust gas flowing to the SCR device 726, the reductant can interact with a greater surface area of the SCR device 726. This can improve performance of the SCR device 726.

[0078] Turning now to Figure 7C which shows an embodiment 740 of a mixer 742 arranged in an exhaust passage 744. The mixer 742 is arranged between a first catalyst 746 and a second catalyst 748. In one example, the catalyst 746 is an oxidation catalyst, and the second catalyst 748 is a lean NOx x trap. The first catalyst 746 and the second catalyst 748 can be other types of catalysts and / or combinations thereof without departing from the scope of the present disclosure.

[0079] Turning now to Figure 7D which shows an embodiment 760 of a mixer 762 arranged in an exhaust passage 764 upstream of an exhaust sensor 766. The exhaust sensor 766 can be used similarly to the exhaust sensor 126 in Figure 1 By arranging the mixer 762 upstream of the exhaust sensor 766, the reliability of the feedback provided by the sensor 766 can be improved, which can improve the operating conditions of the engine. For example, a more accurate air / fuel ratio can be detected by the sensor 766, which can result in improved fuel economy and / or power output.

[0080] In this manner, a compact, easy to manufacture mixer can be located upstream of various exhaust system components to improve the accuracy of sensor readings or improve the efficacy of exhaust aftertreatment devices. Additionally or alternatively, the mixer can be disposed at the junction of an EGR passage and an intake passage to improve the distribution of EGR to each cylinder of an engine. Further, by manufacturing each component to physically couple, the robustness of the mixer is improved so that the mixer does not vibrate or rattle as exhaust gas flows through the mixer. In this manner, the mixer can be quieter than mixers that include longer components or cascading stages. The technical effect of placing the mixer in the passage is to improve the uniformity of the mixture to improve the functionality of components downstream of the mixer.

[0081] One embodiment of a system including a mixing plate disposed between a first passage, a second passage, and an auxiliary passage, each passage coupled to a chamber, and wherein the plate is perforated and includes an S-shaped cross section dividing the chamber into two portions, wherein the first passage is coupled to a first portion and the second passage is coupled to a second portion. A first example of the system further includes wherein the cross section of the plate is undulating. A second example of the system optionally includes the first example, further including wherein the perforations fluidly couple the first portion to the second portion, and wherein gas from the first passage flows through the perforations before flowing to the second passage. A third example of the system, optionally including the first and / or second example, further includes wherein the chamber includes an upstream and a downstream end physically coupled at opposite ends of a tubular wall, and wherein the first passage is coupled to the upstream end, the second passage is coupled to the downstream end, and the auxiliary passage is coupled to the tubular wall. A fourth example of the system, optionally including one or more of the first through third examples, further includes wherein the auxiliary passage is coupled to a portion of the tubular wall corresponding to the first portion. A fifth example of the system, optionally including one or more of the first through fourth examples, further includes wherein the auxiliary passage is an exhaust gas recirculation passage. A sixth example of the system, optionally including one or more of the first through fifth examples, further includes wherein the auxiliary passage is fluidly coupled to an outlet of a reductant injector. A seventh example of the system, optionally including one or more of the first through sixth examples, further includes wherein the first passage and the second passage are radially misaligned with respect to each other about a center of the chamber. An eighth example of the system, optionally including one or more of the first through seventh examples, further includes wherein the chamber and the plate are symmetric about a central axis of the mixer.

[0082] One embodiment of an exhaust mixer includes a perforated circular plate physically coupled to a perforated protrusion having two circular cross-sections merging at a top end; an auxiliary channel physically coupled to the top end of the protrusion, adjacent to a curved protrusion between a first channel and a second channel, wherein the first channel directs a first gas in a first direction, and wherein the auxiliary channel directs a second gas in a second direction opposite the first direction. A first example of the exhaust mixer further includes wherein the circular cross-sections are taken along a plane of the mixer perpendicular to the first and second directions, and wherein cross-sections of the plate and protrusion taken parallel to the first and second directions are triangular. A second example of the exhaust mixer, optionally including the first example, further includes wherein the first channel is separated from both the second channel and the auxiliary channel by the plate and protrusion. A third example of the exhaust mixer, optionally including the first and / or second example, further includes wherein the plate is fixedly coupled to an inner surface of the first channel. A fourth example of the exhaust mixer, optionally including one or more of the first through third examples, further includes wherein the plate and protrusion form a space therebetween, wherein the space is configured to receive gas from the first channel and the auxiliary channel. A fifth example of the exhaust mixer, optionally including one or more of the first through fourth examples, further includes wherein the protrusion further includes a perforated outer surface and a perforated inner surface, and wherein the first gas from the first channel flows through at least the perforations of the plate and the perforations of the outer surface before reaching the second channel, and wherein the second gas from the auxiliary channel flows through at least the inner surface and the perforations of the outer surface before reaching the second channel.

[0083] One embodiment of an engine system includes an inlet passage that is not aligned with an outlet passage, further includes a secondary passage that is angled to both the inlet passage and the outlet passage, and an exhaust mixer disposed adjacent to the intersection of each of the inlet passage, the outlet passage, and the secondary passage, the mixer including a perforated surface separating the passages to force gases from the inlet passage and the secondary passage to flow through the mixer before flowing to the outlet passage. A first example of the engine system further includes where the secondary passage is opposite in direction to the inlet passage and perpendicular to the outlet passage, and where the mixer includes a circular, perforated plate having a diameter equal to the diameter of the inlet passage, the mixer further including a bowl-shaped, perforated protrusion fixedly coupled to the plate and the secondary passage. A second example of the engine system, optionally including the first example, further includes where the inlet passage is vertically lower than the outlet passage and the secondary passage for a vehicle having wheels on the ground, and where the mixer separates the inlet passage and the secondary passage from the outlet passage. A third example of the engine system, optionally including the first and / or second example, further includes where the mixer is immovable, and where there are no other inlets or additional outlets other than the inlet passage, the secondary passage, and the outlet passage. A fourth example of the engine system, optionally including one or more of the first through third examples, further includes where the mixer is housed in a chamber and divides the chamber in half, where a first half of the chamber is directly coupled to the inlet passage and the secondary passage, and a second half of the chamber is directly coupled to the outlet passage.

[0084] Note that the example control and estimation procedures included herein can be used with a variety of engine and / or vehicle system configurations. The control methods and procedures disclosed herein can be stored as executable instructions in non-transitory memory and can be executed by control systems including controllers in combination with various sensors, actuators, and other engine hardware. The specific procedures described herein can represent one or more of any number of processing strategies such as event-driven, interrupt-driven, multi-tasking, multi-threading, and so on. As such, various acts, operations, and / or functions can be performed in the manner shown, in parallel, or in some cases omitted. Likewise, the order of processing is not necessarily restricted to that shown unless specifically required by the examples described herein. Repeating acts, operations, and / or functions can be performed where necessary. Further, the described acts, operations and / or functions can graphically represent code to be programmed into non-transitory memory of a computer readable storage medium of an engine control system. Where the acts are also performed by execution of instructions in a system including various engine hardware components in combination with an electronic controller, the described acts are performed as described.

[0085] It is to be appreciated that the configurations and procedures disclosed herein are exemplary in nature, and that these specific embodiments are not to be considered in a limiting sense, because numerous variations are possible. For example, the above technology can be applied to V-6, I-4, I-6, V-12, opposed 4 cylinder, and other engine types. The subject matter of the present disclosure includes all novel and nonobvious combinations and subcombinations of the various systems and configurations disclosed herein, as well as other features, functions, and / or properties noted herein.

[0086] The appended claims particularly point out certain combinations and subcombinations that are regarded as novel and nonobvious. These claims can refer to "an" element or "a first" element or the equivalent thereof. The claims should be understood to include what comprises one or more such elements, neither requires nor excludes two or more such elements. Other combinations and subcombinations of the disclosed features, functions, elements, and / or properties can be claimed through amendment of the existing claims or presentation of additional claims in the application or corresponding application. Such amended or new claims, whether they are broader, narrower, equal, or different in scope to the original claims, are also regarded as included within the subject matter of the present disclosure.

Claims

1. An engine system comprising: a mixing plate disposed between a first passage, a second passage, and an auxiliary passage, each of the first passage, the second passage, and the auxiliary passage coupled to a chamber, the chamber having a central axis, and wherein the plate is perforated and comprises a cross-section that is S-shaped as viewed along the central axis that divides the chamber into two portions, with the first passage coupled to a first portion and the second passage coupled to a second portion, the perforations distributed across a surface of the plate, and different rows of the perforations capable of directing gas in different angular directions.

2. The engine system of claim 1, wherein the cross-section of the plate is undulating.

3. The engine system of claim 1, wherein the perforations fluidly couple only the first portion to the second portion, and wherein gas from the first passage flows into the first portion, through a perforation, and into the second portion before flowing to the second passage.

4. The engine system of claim 1, wherein the chamber comprises an upstream end and a downstream end physically coupled to opposite ends of a tubular wall, and wherein the first passage is coupled to the upstream end, the second passage is coupled to the downstream end, and the auxiliary passage is coupled to the tubular wall.

5. The engine system of claim 4, wherein the auxiliary passage is coupled to a portion of the tubular wall that corresponds to the first portion.

6. The engine system of claim 4, wherein the auxiliary passage is an exhaust gas recirculation passage.

7. The engine system of claim 4, wherein the auxiliary passage is fluidly coupled to an outlet of an injector.

8. The engine system of claim 1, wherein the first passage and the second passage are radially misaligned with respect to a center of the chamber.

9. The engine system of claim 1, wherein the chamber and the plate are symmetric about a central axis of the mixing plate.

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