METHOD OF REDUCING WARM-UP TIME OF AN AFTERTREATMENT DEVICE AND A VEHICLE SYSTEM FOR THE SAME

A method of reducing warm-up time of an aftertreatment device and a vehicle system for the same are disclosed. Fuel is injected into a plurality of cylinders of an internal combustion engine which is controlled, via a controller. The fuel in a first subset of the plurality of cylinders is combusted to produce a first exhaust product having excess fuel. The fuel in a second subset of the plurality of cylinders is combusted to produce a second exhaust product having excess air. The first exhaust product is expelled through a turbocharger and a valve is actuated to route the second exhaust product away from a dedicated EGR system and downstream from the turbocharger. The excess fuel of the first exhaust product and the excess air of the second exhaust product are mixed downstream from the turbocharger to create an exothermic reaction that produces heat to warm up the aftertreatment device.

Skip to: Description  ·  Claims  · Patent History  ·  Patent History
Description
TECHNICAL FIELD

The present disclosure relates generally to a method of reducing warm-up time of an aftertreatment device and a vehicle system for the same.

BACKGROUND

Internal combustion engines (ICE) can combust a mixture of air and fuel within one or more combustion chambers to produce a mechanical output. During the combustion, various exhaust gases are produced. In some instances, a portion of the exhaust gas can be recirculated back into the engine cylinders (via an exhaust gas recirculation system). In a gasoline engine, this inert exhaust can displace an amount of combustible mixture in the cylinder resulting in increased engine efficiency. The recirculated exhaust gas can reduce the combustion temperature in the cylinder and/or reduce the creation of certain gaseous byproducts.

During start-up or initial warm-up of the ICE, recirculation of the portion of the exhaust gas back to the engine cylinders is not desired, and therefore, a three-way valve can divert this exhaust gas out through an aftertreatment device. Once the ICE is warmed up, the three-way valve can divert the portion of the exhaust gas back to the engine to recirculate this exhaust gas into the engine cylinders.

Internal combustion engines are often called upon to generate considerable levels of power for prolonged periods of time on a dependable basis. Many such ICE assemblies employ a supercharging device, such as an exhaust gas turbine driven turbocharger, to compress the airflow before it enters the intake manifold of the engine in order to increase power and efficiency. Specifically, a turbocharger is a centrifugal gas compressor that forces more air and, thus, more oxygen into the combustion chambers of the ICE than is otherwise achievable with ambient atmospheric pressure. The additional mass of oxygen-containing air that is forced into the ICE improves the engine's volumetric efficiency, allowing it to burn more fuel in a given cycle, and thereby produce more power. Generally, the turbocharger is disposed upstream from the aftertreatment device.

A typical turbocharger includes a central shaft that is supported by one or more bearings and that transmits rotational motion between an exhaust-driven turbine wheel and an air compressor wheel. Both the turbine and compressor wheels are fixed to the shaft, which in combination with various bearing components constitute the turbocharger's rotating assembly.

SUMMARY

The present disclosure provides a method of reducing warm-up time of an aftertreatment device. The method includes controlling, via a controller, an amount of fuel being injected into a plurality of cylinders of an internal combustion engine. The method also includes combusting the fuel in a first subset of the plurality of cylinders to produce a first exhaust product having excess fuel. The method further includes combusting the fuel in a second subset of the plurality of cylinders to produce a second exhaust product having excess air. The method also includes expelling the first exhaust product through a turbocharger and actuating a valve to route the second exhaust product away from a dedicated exhaust gas recirculation system and downstream from the turbocharger. Furthermore, the method includes mixing the excess fuel of the first exhaust product and the excess air of the second exhaust product downstream from the turbocharger to create an exothermic reaction that produces heat to warm up the aftertreatment device.

The present disclosure also provides a vehicle system for reducing warm-up time of an aftertreatment device. The vehicle system including an air intake system, and an internal combustion engine defining a plurality of cylinders and configured to combust a fuel. Each of the plurality of cylinders are coupled with the air intake system. Combustion of the fuel occurs within a first subset of the plurality of cylinders which produces a first exhaust product and combustion of the fuel occurs within a second subset of the plurality of cylinders which produces a second exhaust product. The vehicle system also includes an exhaust system in fluid communication with the first subset of the plurality of cylinders and a turbocharger in fluid communication with the exhaust system. The turbocharger expels the first exhaust product. The vehicle system further includes a dedicated exhaust gas recirculation system in selective fluid communication with the second subset of the plurality of cylinders and the air intake system to route the second exhaust product from the second subset of the plurality of cylinders to the air intake system. The vehicle system also includes a valve coupled with the dedicated exhaust gas recirculation system to selectively route the second exhaust product downstream from the turbocharger such that the first and second exhaust products mix downstream from the turbocharger to create an exothermic reaction. Furthermore, the vehicle system includes a controller, having a processor and tangible, non-transitory memory on which is recorded instructions. Executing the recorded instructions causes the processor to control an amount of fuel being injected into the plurality of cylinders of the internal combustion engine, and actuate the valve to route the second exhaust product away from the dedicated exhaust gas recirculation system and downstream from the turbocharger.

The detailed description and the drawings or Figures are supportive and descriptive of the disclosure, but the scope of the disclosure is defined solely by the claims. While some of the best modes and other embodiments for carrying out the claims have been described in detail, various alternative designs and embodiments exist for practicing the disclosure defined in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a vehicle system including an internal combustion engine with a dedicated exhaust gas recirculation system.

 DETAILED DESCRIPTION

Referring to the drawings, wherein like numerals indicate like or corresponding parts throughout the several views, FIG. 1 schematically illustrates a vehicle system 10 including an internal combustion engine 12, an air intake system 14, and an exhaust system 16. The air intake system 14 and the exhaust system 16 can each respectively be in fluid communication with the engine 12, and can be in mechanical communication with each other through a turbocharger 18.

The internal combustion engine 12 (i.e., engine 12) can be a spark-ignited internal combustion engine or any other suitable internal combustion engine, and can define a plurality of cylinders 20 (referenced as cylinders 1-4). Generally, the engine 12 is configured to combust a fuel. Each of the respective cylinders 20 can include one or more fuel injectors 22 that can selectively introduce liquid fuel (as an aerosol) into each cylinder for combustion. In FIG. 1, each of the plurality of cylinders 20 includes one fuel injector 22.

Each of the plurality of cylinders 20 can be in selective fluid communication with the air intake system 14 to receive fresh/oxygenated air, and each of the plurality of cylinders 20 can be in selective fluid communication with the exhaust system 16 to, for example, expel the byproducts of combustion. While the illustrated engine 12 depicts a 4-cylinder engine, the present technology is equally applicable to inline two, three and six cylinder engines, V-2, V-4, V-6, V-8, V-10, and V-12 configuration engines, among others.

In certain embodiments, each of the plurality of cylinders 20 are coupled with the air intake system 14. The air intake system 14 can generally include, one or more of, a fresh-air inlet 24, an exhaust gas recirculation (EGR) mixer 26, a charge air cooler 28, a throttle 30, and an intake manifold 32. As may be appreciated during operation of the engine 12, fresh air or intake air 34 can be ingested by the air intake system 14 from the atmosphere (or from an associated air-cleaner assembly) via the fresh-air inlet 24. The throttle 30 can include a controllable baffle configured to selectively regulate the total flow of air through the air intake system 14, and ultimately into the cylinders 20 (via the intake manifold 32).

As generally shown in FIG. 2, the charge air cooler 28 can be disposed between the EGR mixer 26 and the throttle 30. In general, the charge air cooler 28 can be a radiator-style heat exchanger that can use a flow of atmospheric air or liquid coolant to cool the fresh air/exhaust gas mixture. As may be appreciated, the gas mixture can be warmer than atmospheric temperature due to the pressurization via the compressor 52, along with the mixing of the high-temperature exhaust gas of the second exhaust product 41. The charge air cooler 28 can cool the gas mixture to increase its density/volumetric efficiency, while also reducing the potential for abnormal combustion.

The charge air cooler 28 can include a plurality of closed cooling passageways that fluidly couple an inlet volume with an outlet volume. The cooling passageways can be formed from a thermally conductive material, such as aluminum, and can further include a plurality of heat transfer features, such as fins or wires, that can promote heat transfer between the externally flowing atmospheric air or liquid coolant and the internally contained gas mixture.

The exhaust system 16 can include an exhaust manifold 36 that generally guides flowing exhaust gas away from the engine 12. Combustion of the fuel occurs within a first subset of the plurality of cylinders 20 which produces a first exhaust product 40. For example, the first subset of the plurality of cylinders 20 can be, as referenced in FIG. 1, cylinders 1-3, and the first exhaust product 40 can be exhaust gas, which is discussed further below. The exhaust system 16 is in fluid communication with the first subset of the plurality of cylinders 20. Therefore, the first exhaust product 40 can be expelled through the exhaust system 16. Specifically, the first exhaust product 40 can be guided through the exhaust manifold 36 away from the engine 12. In certain embodiments, optionally, the exhaust flow from the cylinders 20 can be divided into different flows, which can be separately routed to the turbocharger 18 via multiple exhaust manifolds.

Combustion of the fuel also occurs within a second subset of the plurality of cylinders 20 which produces a second exhaust product 41. For example, the second subset of the plurality of cylinders 20 can be, as referenced in FIG. 1, cylinder 4, and the second exhaust product 41 can be exhaust gas, which is discussed further below.

Generally, the exhaust gas can eventually pass through an aftertreatment device 42 to catalyze and/or remove certain byproducts prior to exiting the exhaust system 16 via a tailpipe 44. The aftertreatment device 42 can include a catalyst, a three-way catalyst or any other suitable components/catalysts, etc., to catalyze and/or remove various byproducts prior to exiting the exhaust system 16.

The air intake system 14 and the exhaust system 16 can be in mechanical communication through a turbocharger 18. Generally, the turbocharger 18 is in fluid communication with the exhaust system 16 and the turbocharger 18 expels the first exhaust product 40. The turbocharger 18 can include a turbine 50 in fluid communication with the exhaust system 16 and a compressor 52 in fluid communication with the air intake system 14. The turbine 50 and the compressor 52 can be mechanically coupled via a rotatable shaft 54. The turbocharger 18 can utilize the energy of the first exhaust product 40 flowing from the engine 12 to spin the turbine 50 and the compressor 52. The rotation of the compressor 52 can then draw fresh air 34 in from the inlet 24 and compress the air 34 into the remainder of the air intake system 14. The first exhaust product 40 is expelled through the turbocharger 18. Once the first exhaust product 40 is expelled from the turbocharger 18, the first exhaust product 40 flows toward the aftertreatment device 42.

The vehicle system 10 can further include a dedicated EGR system 60 that can selectively route (e.g., via an EGR manifold 62) the second exhaust product 41 from one or more of the cylinders 20 of the engine 12 back into the air intake system 14. Specifically, the dedicated EGR system 60 is in selective fluid communication with the second subset of the plurality of cylinders 20 and the air intake system 14 to route the second exhaust product 41 from the second subset of the plurality of cylinders 20 to the air intake system 14. This recirculated second exhaust product 41, such as exhaust gas, can mix with the fresh air 34 at the EGR mixer 26, and can correspondingly dilute the oxygen content of the mixture. The use of the dedicated EGR system 60 can increase efficiency, such as fuel efficiency, in spark ignition engines. Furthermore, the dedicated EGR system 60 can reduce the combustion temperature and NOx production from the engine 12. Using a separate EGR manifold 62 to route the second exhaust product from one or more cylinders 20 back to the air intake system 14 is referred to herein as “dedicated EGR.”

With continued reference to FIG. 1, one of the cylinders 20 (i.e., cylinder 4) is a dedicated EGR cylinder that can selectively supply all of the second exhaust product 41 back to the air intake system 14. As mentioned above, the first exhaust product 40 of the remaining three cylinders 20 (i.e., cylinders 1-3) is expelled from the engine 12 via the exhaust system 16 through the aftertreatment device 42.

During start-up or initial warm-up of the engine 12, it is desirable to route the second exhaust product 41 away from the engine 12. In other words, the second exhaust product 41 bypasses the dedicated EGR system 60 and is expelled through the aftertreatment device 42. A valve 64 can be utilized to selectively route the second exhaust product 41 through the dedicated EGR system 60. Therefore, the valve 64 can selectively route the second exhaust product 41 away from the dedicated EGR system 60 during warm-up of the engine 12. Once the desired temperature is reached, for example in the engine 12 or the aftertreatment device 42, the valve 64 can then route the second exhaust product 41 through the dedicated EGR system 60. Specifically, the valve 64 can be coupled with the dedicated EGR system 60 to selectively route the second exhaust product 41 downstream from the turbocharger 18 to bypass the dedicated EGR system 60 or route the second exhaust product 41 through the dedicated EGR system 60 back to the air intake system 14. It is to be appreciated that the valve 64 can be any suitable type of valve, and examples of suitable valves are a three-way valve or a bypass valve.

Warming up the aftertreatment device 42 quickly can contribute to efficiently controlling emissions expelled from the engine 12. Therefore, it is desirable to reduce the warm-up time of the aftertreatment device 42. The turbocharger 18 is disposed upstream from the aftertreatment device 42 and the turbine 50 of the turbocharger 18 can cause heat loss from the exhaust gas due to the components of the turbine 50 being heated first by the exhaust gas before the exhaust gas reaches the downstream aftertreatment device 42. Heat loss of the exhaust gas to the turbine 50 means that the warm-up time of the aftertreatment device 42 can be impeded. One way to reduce the warm-up time of the aftertreatment device 42, in light of the above, is to mix the first exhaust product 40 and the second exhaust product 41 downstream from the turbocharger 18 and upstream from the aftertreatment device 42, which creates an exothermic reaction 66 to produce heat that warms up the aftertreatment device 42. Simply stated, the exothermic reaction 66 produces heat that expedites warming up of the aftertreatment device 42. The exothermic reaction 66 does not lose heat to the turbocharger 18 because the reaction 66 occurs downstream from the turbocharger 18, and instead, the exothermic reaction 66 warms up the aftertreatment device 42 first. Specifically, the exothermic reaction 66 produces heat that directly expedites the warm up of the aftertreatment device 42 because the reaction 66 occurs immediately before the aftertreatment device 42. The location that the exothermic reaction 66 occurs expedites warming up the aftertreatment device 42. The exothermic reaction 66 occurs between the turbocharger 18 and the aftertreatment device 42, and therefore, after the reaction, the heated exhaust gas flows through the aftertreatment device 42. Once the aftertreatment device 42 is warmed up and operational, i.e., reaches the desired temperature, the dedicated EGR system 60 can then be utilized to recirculate the second exhaust product 41 back to the air intake system 14.

Generally, the valve 64 is disposed between the second subset of the plurality of cylinders 20, i.e., in FIG. 1 cylinder 4, and the dedicated EGR system 60. The valve 64 is coupled with the dedicated EGR system 60 to selectively route the second exhaust product 41 downstream from the turbocharger 18 such that the first and second exhaust products 40, 41 mix downstream from the turbocharger 18 to create the exothermic reaction 66. The exothermic reaction 66 reduces the warm-up time of the aftertreatment device 42 as compared to not creating this reaction. Furthermore, the location of the exothermic reaction 66 reduces the warm-up time of the aftertreatment device 42 as compared to creating this reaction at another location or not creating this reaction at that location.

The valve 64 can be actuated to change the direction of flow of the second exhaust product 41. For example, the valve 64 can be actuated to a first position to route the second exhaust product 41 toward the aftertreatment device 42 and bypasses the dedicated EGR system 60. The valve 64 can also be actuated to a second position that routes the second exhaust product 41 through the dedicated ERG system 60 back to the air intake system 14. Therefore, the second subset of the plurality of cylinders 20 (i.e., cylinder 4 in FIG. 1) is a dedicated EGR cylinder, and when the valve 64 is in the second position, all of the second exhaust product 41 is routed back to the intake system 14, and when the valve 64 is in the first position, all of the second exhaust product 41 is routed through the aftertreatment device 42.

A first conduit 68 is disposed between the turbocharger 18 and the aftertreatment device 42 to guide the first exhaust product 40 toward the aftertreatment device 42. A second conduit 70 is coupled with the valve 64 and the first conduit 68 to guide the second exhaust product 41 into the first conduit 68 to mix the first and second exhaust products 40, 41 when the valve 68 is in the first position. Therefore, the valve 64 is disposed between the second conduit 70 and the second subset of the plurality of cylinders 20. The valve 64 is in fluid communication with the aftertreatment device 42 when in the first position and the valve 64 is in fluid communication with the dedicated EGR system 60 when in the second position.

A controller 72 can be part of an electronic control module that is in communication with various components of the vehicle. The controller 72 includes a processor 74 and a memory 76 on which is recorded instructions for communicating with the valve 64, the fuel injectors 22, the turbocharger 18, the aftertreatment device 42, etc. The controller 72 is configured to execute the instructions from the memory 76, via the processor 74. For example, the controller 72 can be a host machine or distributed system, e.g., a computer such as a digital computer or microcomputer, acting as a vehicle control module, and/or as a proportional-integral-derivative (PID) controller device having a processor, and, as the memory 76, tangible, non-transitory computer-readable memory such as read-only memory (ROM) or flash memory. The controller 72 can also have random access memory (RAM), electrically erasable programmable read only memory (EEPROM), a high-speed clock, analog-to-digital (A/D) and/or digital-to-analog (D/A) circuitry, and any required input/output circuitry and associated devices, as well as any required signal conditioning and/or signal buffering circuitry. Therefore, the controller 72 can include all software, hardware, memory 76, algorithms, connections, sensors, etc., necessary to monitor and control the valve 64, the fuel injectors 22, the turbocharger 18, the aftertreatment device 42, etc. As such, a control method can be embodied as software or firmware associated with the controller 72. It is to be appreciated that the controller 72 can also include any device capable of analyzing data from various sensors, comparing data, making the necessary decisions required to control and monitor the valve 64, the fuel injectors 22, the turbocharger 18, the aftertreatment device 42, etc.

The controller 72, having the processor 74 and tangible, non-transitory memory 76 on which is recorded instructions, and wherein the controller 72 is configured to control an amount of fuel being injected into the plurality of cylinders 20 of the internal combustion engine 12 and actuate the valve 64 to route the second exhaust product 41 away from the dedicated EGR system 60 and downstream from the turbocharger 18. Furthermore, the controller 72 is configured to actuate the valve 64 in the first position that routes the second exhaust product 41 toward the aftertreatment device 42 and bypasses the dedicated EGR system 60, and the second position that routes the second exhaust product 41 through the dedicated EGR system 60 back to the air intake system 14.

Additionally, the controller 72 is configured to signal the fuel injector 22 of each of the plurality of cylinders 20 to inject a predetermined amount of fuel into each of the plurality of cylinders 20 to produce the first exhaust product 40 having the excess fuel and the second exhaust product 41 having the excess air. Furthermore, the controller 72 is configured to signal the fuel injector 22 of each of the plurality of cylinders 20 to operate in one of a first mode and a second mode. When in the first mode, combusting the fuel in the first subset of the plurality of cylinders 20, i.e., cylinders 1-3, produces the first exhaust product 40 having excess fuel and combusting the fuel in the second subset of the plurality of cylinders 20, i.e., cylinder 4, produces the second exhaust product 41 having excess air. Therefore, the first exhaust product 40 having excess fuel can also be referred to as a rich mixture and the second exhaust product 41 having excess air can also be referred to as a lean mixture. Generally, the first mode occurs during initial start-up or warm-up of the engine 12, and thus, initial start-up or warm-up of the aftertreatment device 42. During warm-up, the rich and lean mixtures react to create the exothermic reaction 66. When the engine 12/aftertreatment device 42 is adequately warmed up to contribute to efficiently controlling emissions expelled from the engine 12, the controller 72 will signal various components to switch to the second mode.

For example, the controller 72 can signal one or more of the fuel injectors 22 to change the amount of fuel entering respective cylinders 20 when in the second mode. The controller 72 can signal the valve 64 to close the fluid path through the second conduit 70 and open the fluid path through the dedicated EGR system 60 when in the second mode. Therefore, the dedicated EGR system 60 is bypassed when in the first mode and is utilized when in the second mode. Also, the controller 72 is configured to signal the fuel injector 22 of the first subset of the plurality of cylinders 20 to inject a predetermined amount of fuel into the first subset of the plurality of cylinders 20 when in the first mode and inject a predetermined amount of fuel into the second subset of the plurality of cylinders 20 when in the first mode. Generally, the amount of fuel injected into the second subset is less than the first subset when in the first mode.

The first exhaust product 40 is expelled out of the exhaust manifold 36, through the turbocharger 18 toward the aftertreatment device 42. As such, the first exhaust product 40 exits the turbocharger 18 to mix with the second exhaust product 41 when the valve 64 is in the first position. The turbocharger 18 expels the first exhaust product 40 regardless of which position the valve 64 is in. Therefore, the turbocharger 18 expels the first exhaust product 40 when the valve 64 is in the first position or the second position. Generally, the controller 72 can communicate with the turbocharger 18.

To determine the temperature of the aftertreatment device 42, a sensor 78, an algorithm and/or time can be utilized. For example, optionally, as shown in FIG. 1, the sensor 78 can be coupled to the aftertreatment device 42 and the controller 72 can be in communication with the sensor 78. Alternatively, or in addition to, the controller 72 can utilize an algorithm to determine when the aftertreatment device 42 is warmed-up. It is to be appreciated that any suitable components or methods can be utilized to determine the temperature of the aftertreatment device 42 and/or when the aftertreatment device 42 is adequately warmed-up to contribute to efficiently controlling emissions expelled from the engine 12.

The present disclosure also provides a method of reducing warm-up time of the aftertreatment device 42. Reducing the warm-up time of the aftertreatment device 42 allows the aftertreatment device 42 to contribute to efficiently controlling emissions expelled from the engine 12 quicker. The method includes controlling, via the controller 72, an amount of fuel being injected into a plurality of cylinders 20 of the internal combustion engine 12.

The method further includes combusting the fuel in the first subset of the plurality of cylinders 20, i.e., cylinders 1-3, to produce the first exhaust product 40 having excess fuel and combusting the fuel in the second subset of the plurality of cylinders 20, i.e., cylinder 4, to produce the second exhaust product 41 having excess air. Excess air means that more oxygen is exiting the second subset of the plurality of cylinders 20.

The method also includes expelling the first exhaust product 40 through the turbocharger 18 and actuating the valve 64 to route the second exhaust product 41 away from the dedicated EGR system 60 and downstream from the turbocharger 18. In certain embodiments, actuating the valve 64 can include actuating the valve 64 in the first position that routes the second exhaust product 41 toward the aftertreatment device 42 and bypasses the dedicated EGR system 60, and the second position that routes the second exhaust product 41 through the dedicated EGR system 60 back to the air intake system 14. Furthermore, in certain embodiments, actuating the valve 64 can further include signaling the valve 64, via the controller 72, to switch between the first and second positions. Furthermore, expelling the first exhaust product 40 through the turbocharger 18 can include expelling the first exhaust product 40 toward the aftertreatment device 42 to mix with the second exhaust product 41 when the valve 64 is in the first position. Therefore, regardless of whether the turbocharger 18 is operating, the first exhaust product 40 exits the turbocharger 18 and flows toward the aftertreatment device 42.

The method further includes mixing the excess fuel of the first exhaust product 40 and the excess air of the second exhaust product 41 downstream from the turbocharger 18 to create the exothermic reaction 66 that produces heat to warm up the aftertreatment device 42. In certain embodiments, mixing the excess fuel of the first exhaust product 40 and the excess air of the second exhaust product 41 downstream from the turbocharger 18 can include mixing the excess fuel and the excess air between the turbocharger 18 and the aftertreatment device 42 such that the exothermic reaction 66 occurs upstream from the aftertreatment device 42 and the heat produced from the exothermic reaction 66 is directed toward the aftertreatment device 42. Therefore, the fuel and the air, i.e., oxygen, create the exothermic reaction 66 to reduce the warm-up time of the aftertreatment device 42. The faster the warm-up time, the sooner the emissions expelled from the engine 12 can be adequately controlled.

In certain embodiments, controlling, via the controller 72, the amount of fuel being injected into the plurality of cylinders 20 can include signaling the fuel injector 22 of each of the plurality of cylinders 20, via the controller 72, to inject a predetermined amount of fuel into each of the plurality of cylinders 20 to produce the first exhaust product 40 having the excess fuel and the second exhaust product 41 having the excess air. Furthermore, signaling the fuel injector 22 of each of the plurality of cylinders 20, via the controller 72, can include signaling the fuel injector 22 of each of the plurality of cylinders 20 to operate in one of a first mode and a second mode. Generally, the first exhaust product 40 having the excess fuel and the second exhaust product 41 having the excess air occurs when in the first mode.

The method can also include injecting a predetermined amount of fuel into the first subset of the plurality of cylinders 20, via the fuel injector 22, when in the first mode and injecting a predetermined amount of fuel into the second subset of the plurality of cylinders 20, via the fuel injector 22, when in the first mode. Generally, when in the first mode, the amount of fuel injected into the second subset is less than the first subset. In various embodiments, injecting a predetermined amount of fuel into the first subset of the plurality of cylinders 20, via the fuel injector 22, when in the first mode can include injecting the same amount of fuel into each of the plurality of cylinders 20 of the first subset when in the first mode.

In certain embodiments, signaling the fuel injector 22 of each of the plurality of cylinders 20 to operate in one of the first mode and the second mode can include signaling the fuel injector 22 of each of the plurality of cylinders 20 to operate in the second mode to change the amount of fuel being injected into at least one of the first subset and the second subset of the plurality of cylinders 20, which changes at least one of the first exhaust product 40 and the second exhaust product 41 being produced during combustion. In various embodiments, signaling the fuel injector 22 of each of the plurality of cylinders 20 to operate in the second mode to change the amount of fuel being injected into at least one of the first subset and the second subset of the plurality of cylinders 20 can further include signaling the fuel injector 22 of each of the plurality of cylinders 20 to operate in the second mode to change the amount of fuel being injected into both of the first subset and the second subset of the plurality of cylinders 20, which changes the first exhaust product 40 and the second exhaust product 41 being produced during combustion. Simply stated, when the amount of fuel being injected into one or more of the first subset of the plurality of cylinders 20 changes, the first exhaust product 40 correspondingly changes. Furthermore, when the amount of fuel being injected into one or more of the second subset of the plurality of cylinders 20 changes, the second exhaust product 41 correspondingly changes. Changes for any of these cylinders 20 can include adding or reducing the amount of fuel being injected.

While the best modes for carrying out the disclosure have been described in detail, those familiar with the art to which this disclosure relates will recognize various alternative designs and embodiments for practicing the disclosure within the scope of the appended claims. Furthermore, the embodiments shown in the drawings or the characteristics of various embodiments mentioned in the present description are not necessarily to be understood as embodiments independent of each other. Rather, it is possible that each of the characteristics described in one of the examples of an embodiment can be combined with one or a plurality of other desired characteristics from other embodiments, resulting in other embodiments not described in words or by reference to the drawings. Accordingly, such other embodiments fall within the framework of the scope of the appended claims.

Claims

1. A method of reducing warm-up time of an aftertreatment device, the method comprising:

controlling, via a controller, an amount of fuel being injected into a plurality of cylinders of an internal combustion engine;
combusting the fuel in a first subset of the plurality of cylinders to produce a first exhaust product having excess fuel;
combusting the fuel in a second subset of the plurality of cylinders to produce a second exhaust product having excess air;
expelling the first exhaust product through a turbocharger;
actuating a valve to route the second exhaust product away from a dedicated exhaust gas recirculation system and downstream from the turbocharger; and
mixing the excess fuel of the first exhaust product and the excess air of the second exhaust product downstream from the turbocharger to create an exothermic reaction that produces heat to warm up the aftertreatment device.

2. The method of claim 1, wherein controlling, via the controller, the amount of fuel being injected into the plurality of cylinders further comprises signaling a fuel injector of each of the plurality of cylinders, via the controller, to inject a predetermined amount of fuel into each of the plurality of cylinders to produce the first exhaust product having the excess fuel and the second exhaust product having the excess air.

3. The method of claim 2, wherein signaling the fuel injector of each of the plurality of cylinders, via the controller, further comprises signaling the fuel injector of each of the plurality of cylinders to operate in one of a first mode and a second mode, with the first exhaust product having the excess fuel and the second exhaust product having the excess air when in the first mode.

4. The method of claim 3, further comprising injecting a predetermined amount of fuel into the first subset of the plurality of cylinders, via the fuel injector, when in the first mode and injecting a predetermined amount of fuel into the second subset of the plurality of cylinders, via the fuel injector, when in the first mode, with the amount of fuel injected into the second subset being less than the first subset.

5. The method of claim 3, wherein signaling the fuel injector of each of the plurality of cylinders to operate in one of the first mode and the second mode further comprises signaling the fuel injector of each of the plurality of cylinders to operate in the second mode to change the amount of fuel being injected into at least one of the first subset and the second subset of the plurality of cylinders, which changes at least one of the first exhaust product and the second exhaust product being produced during combustion.

6. The method of claim 3, wherein signaling the fuel injector of each of the plurality of cylinders to operate in the second mode to change the amount of fuel being injected into at least one of the first subset and the second subset of the plurality of cylinders further comprises signaling the fuel injector of each of the plurality of cylinders to operate in the second mode to change the amount of fuel being injected into both of the first subset and the second subset of the plurality of cylinders, which changes the first exhaust product and the second exhaust product being produced during combustion.

7. The method of claim 3, wherein injecting a predetermined amount of fuel into the first subset of the plurality of cylinders, via the fuel injector, when in the first mode further comprises injecting the same amount of fuel into each of the plurality of cylinders of the first subset when in the first mode.

8. The method of claim 1, wherein actuating the valve further comprises actuating the valve in a first position that routes the second exhaust product toward the aftertreatment device and bypasses the dedicated exhaust gas recirculation system, and a second position that routes the second exhaust product through the dedicated exhaust gas recirculation system back to an air intake system.

9. The method of claim 8, wherein mixing the excess fuel of the first exhaust product and the excess air of the second exhaust product downstream from the turbocharger further comprises mixing the excess fuel and the excess air between the turbocharger and the aftertreatment device such that the exothermic reaction occurs upstream from the aftertreatment device and the heat produced from the exothermic reaction is directed toward the aftertreatment device.

10. The method of claim 8, wherein actuating the valve further comprises signaling the valve, via the controller, to switch between the first and second positions.

11. The method of claim 8, wherein expelling the first exhaust product through the turbocharger further comprises expelling the first exhaust product toward the aftertreatment device to mix with the second exhaust product when the valve is in the first position.

12. A vehicle system for reducing warm-up time of an aftertreatment device, the system comprising:

an air intake system;
an internal combustion engine defining a plurality of cylinders and configured to combust a fuel;
wherein each of the plurality of cylinders are coupled with the air intake system;
wherein combustion of the fuel occurs within a first subset of the plurality of cylinders which produces a first exhaust product;
wherein combustion of the fuel occurs within a second subset of the plurality of cylinders which produces a second exhaust product;
an exhaust system in fluid communication with the first subset of the plurality of cylinders;
a turbocharger in fluid communication with the exhaust system, wherein the turbocharger expels the first exhaust product;
a dedicated exhaust gas recirculation system in selective fluid communication with the second subset of the plurality of cylinders and the air intake system to route the second exhaust product from the second subset of the plurality of cylinders to the air intake system;
a valve coupled with the dedicated exhaust gas recirculation system to selectively route the second exhaust product downstream from the turbocharger such that the first and second exhaust products mix downstream from the turbocharger to create an exothermic reaction; and
a controller, having a processor and tangible, non-transitory memory on which is recorded instructions, wherein the controller is configured to: control an amount of fuel being injected into the plurality of cylinders of the internal combustion engine; and actuate the valve to route the second exhaust product away from the dedicated exhaust gas recirculation system and downstream from the turbocharger.

13. The vehicle system of claim 12, further comprising an aftertreatment device, and wherein the exothermic reaction produces heat that warms up the aftertreatment device.

14. The vehicle system of claim 13, wherein the controller is configured to actuate the valve in a first position that routes the second exhaust product toward the aftertreatment device and bypasses the dedicated exhaust gas recirculation system, and a second position that routes the second exhaust product through the dedicated exhaust gas recirculation system back to the air intake system.

15. The vehicle system of claim 14, further including a first conduit disposed between the turbocharger and the aftertreatment device to guide the first exhaust product toward the aftertreatment device, and further including a second conduit coupled with the valve and the first conduit to guide the second exhaust product into the first conduit to mix the first and second exhaust products when the valve is in the first position.

16. The vehicle system of claim 12, wherein the controller is configured to signal a fuel injector of each of the plurality of cylinders to inject a predetermined amount of fuel into each of the plurality of cylinders to produce the first exhaust product having the excess fuel and the second exhaust product having the excess air.

17. The vehicle system of claim 16, wherein the controller is configured to signal the fuel injector of each of the plurality of cylinders to operate in one of a first mode and a second mode, with the first exhaust product having the excess fuel and the second exhaust product having the excess air when in the first mode.

18. The vehicle system of claim 17, wherein the controller is configured to signal the fuel injector of the first subset of the plurality of cylinders to inject a predetermined amount of fuel into the first subset of the plurality of cylinders when in the first mode and inject a predetermined amount of fuel into the second subset of the plurality of cylinders when in the first mode, with the amount of fuel injected into the second subset being less than the first subset.

Patent History
Publication number: 20160017783
Type: Application
Filed: Jul 17, 2014
Publication Date: Jan 21, 2016
Inventor: Edward J. Keating (Ortonville, MI)
Application Number: 14/334,074
Classifications
International Classification: F01N 3/20 (20060101);