Method and system for a particulate filter

Abstract

The present invention relates to methods and systems for particulate filters, and methods and systems for particulate filters including pretreatment are disclosed. In one example, the method may include applying the pretreatment to an unused particulate filter, wherein the particulate filter is subjected to incomplete oxidation conditions after applying the pretreatment.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to German Patent Application No. 102017218573.2 filed on October 18, 2017, German Patent Application No. 102017218572.4 filed on October 18, 2017, and German Patent Application No. 102017218574.0 filed on October 18, 2017. The entire contents of the above-referenced applications are hereby incorporated by reference in their entirety for all purposes. Technical Field

[0003] The present description generally relates to engines having particulate filters. Background Art

[0004] Particulate filters are increasingly being used in the exhaust lines of both diesel engines and spark-ignition engines to filter out soot particles from the exhaust flow, thereby reducing emissions. The particulate filter may be regenerated at certain intervals, which may include actively or passively increasing the exhaust temperature to burn the trapped soot particles. As a result of regeneration, ash deposits may accumulate on the particulate filter surface.

[0005] Other attempts to address emissions include preloading the particulate filter with a minimum load. An example approach is shown in US 9,027,333 by Neely et al. Therein, it is described that a particulate filter with a certain degree of soot loading is more effective in preventing hydrocarbon emissions during cold engine starts than an unloaded particulate filter. Therefore, it is suggested to ensure a certain minimum soot loading of the particulate filter to improve the filter efficiency. This can be achieved by controlling the regeneration of the particulate filter so that not all soot particles are burned during regeneration, but a certain minimum load is maintained in the particulate filter. This may also be referred to as partial regeneration.

[0006] However, the inventors herein have recognized potential problems with such systems. As an example, using this approach, a minimum load can only be achieved after a certain period of engine operation, since soot particles are only formed during engine operation. However, at initial engine start-up, the filter efficiency remains low. In addition, soot loading leads to a severe build-up of exhaust back pressure, which can result in increased fuel consumption and also increases the likelihood of knock in a spark-ignition engine under heavy load. Therefore, a way of ensuring adequate filter performance right from the initial engine start-up is still desired. It is also desirable to reduce the build-up of exhaust back pressure and largely avoid the disadvantages associated therewith. Summary of the invention

[0007] In one example, the above problem can be solved by a method for: manufacturing a particulate filter; applying a hydrocarbon-containing composition to at least a portion of the particulate filter; placing the particulate filter in an exhaust passage of a vehicle; and adjusting engine operating parameters during a first combustion period of an engine of the vehicle to not completely oxidize the hydrocarbon-containing composition. In this way, a soot layer can be formed on the particulate filter more quickly, thereby reducing the duration of a breaking-in period.

[0008] As an example, in anticipation of partial oxidation of the pretreatment, the pore size of the particulate filter may be set slightly larger than the desired pore size. Once the pretreatment is oxidized, a soot layer may form, which may reduce the pore size of the pores to the desired pore size. By doing so, larger pores may be utilized, which may reduce the drawbacks of higher exhaust back pressure.

[0009] It should be understood that the above summary is provided to introduce selected concepts further described in the detailed description in a simplified form. This is not meant to identify key or essential features of the claimed subject matter, the scope of which is uniquely defined by the appended claims. Furthermore, the claimed subject matter is not limited to embodiments that address any disadvantages mentioned above or in any part of this disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 An engine of a hybrid vehicle is shown.

[0011] Figure 2 An exemplary pore size distribution for the previous example of a particulate filter is shown.

[0012] Figure 3 An exemplary pore size distribution for the present example of a particulate filter is shown.

[0013] Figure 4 The number of microparticles released in consecutive tests is shown.

[0014] Figure 5 A method for adjusting a particulate filter to reduce the break-in period is shown.

[0015] Figure 6 Methods for on-board administration of pre-treatment in response to sensed exhaust back pressure and partial oxidation of the pre-treatment are shown. DETAILED DESCRIPTION

[0016] The following description relates to systems and methods for using a particulate filter in an exhaust line of a spark-ignition engine, wherein the filter efficiency (e.g., the ratio of filtered particles to all particles of a specific size present) increases significantly after a certain initial operating period (a run-in period), which in a spark-ignition engine corresponds to a travel distance of approximately 3000 km. This may be attributed to the formation of a soot layer or filter cake on the surface of the particulate filter formed by soot particles present in the exhaust gas flow. In other words, a newly manufactured vehicle that has not traveled more than approximately 3000 km may not include a sufficient soot layer or filter cake formed on the particulate filter. As such, the particulate filter of a newly manufactured vehicle may function at a less than desired filter efficiency, resulting in increased emissions.

[0017] In order to ensure that particulate pollutants are adequately filtered right from the initial start of an engine with a particulate filter, it may be desirable for a new particulate filter to include a smaller pore size to take advantage of a smaller soot layer, thereby reducing the break-in period. However, this may be disadvantageous after a certain operating period, as the combination of a small pore size and a forming soot layer further increases exhaust back pressure, thus amplifying the associated adverse effects explained above.

[0018] After the running-in time has expired, significantly larger pore sizes can be selected without any significant reduction in filter efficiency, since the soot- and / or ash-containing layer that has now formed also contributes to the filtration.

[0019] As such, the present disclosure is directed to making and using a particulate filter whose porosity is adapted for conditions after a break-in period has concluded.

[0020] However, in order to ensure adequate filter efficiency also during the run-in period, it is recommended to coat the surface of the unused particle filter with a hydrocarbon-containing composition, from which soot is then formed by incomplete oxidation. To this end, the hydrocarbon-containing composition can, for example, be incompletely combusted during the first operation of the internal combustion engine. The soot formed further contributes to the filtration and thus increases the filter efficiency.

[0021] The method for pretreating a particulate filter according to the present disclosure includes applying a hydrocarbon-containing composition to a surface of the particulate filter and subsequently forming soot on the surface of the particulate filter via incomplete oxidation of the hydrocarbon-containing composition. The incomplete oxidation here relates to carbon of the hydrocarbon-containing composition. The formation of soot on the surface of the particulate filter loads the particulate filter with soot.

[0022] The particle filter may be, for example, a wall-flow filter or a partial flow filter. The particle filter may include filter walls of different porous materials (such as ceramic or metal) and may be arranged in a housing. The particle filter may be provided with a catalytic coating (e.g., a coating for selective catalytic reduction, for oxidation of carbon monoxide and / or hydrocarbons, or for a three-way catalyst). The particle filter may be used, for example, for post-treatment of exhaust gas from an internal combustion engine.

[0023] The particle filter surface may be defined as the area that is in contact with the exhaust gas flow when the particle filter is arranged in the exhaust line. Internal surfaces, such as the surfaces of the pores of the particle filter, are therefore also included as particle filter surfaces. Soot may accumulate on at least a portion of the particle filter surface.

[0024] Soot may be defined as a composition produced, for example, upon incomplete oxidation, in particular incomplete combustion, of a hydrocarbonaceous composition. Soot may, for example, comprise a proportion between 80 wt.% and 99.5 wt.% of carbon as well as sulfates, condensed hydrocarbons and / or ash.

[0025] The formation of soot enables the use of a particulate filter with a larger pore size, so that the exhaust back pressure is low and increases only minimally during the use of the particulate filter, but in any case is less than when using a particulate filter with a smaller pore size. In this way, fuel consumption can be reduced and the knock tendency can be reduced.

[0026] Soot formed as a result of pretreatment including the hydrocarbon-containing composition may allow the particulate filter to capture a desired amount of soot and / or operate at a desired particulate filter efficiency during a break-in period when other particulate filters not including pretreatment may function at less than a desired particulate filter efficiency.

[0027] The method according to the present disclosure is used to pretreat a newly manufactured particulate filter, which has not yet been used as intended. In other words, the particulate filter has not been put into its intended use before the hydrocarbon-containing composition is applied. That is, the pretreatment comprising the hydrocarbon-containing composition is applied to a particulate filter that does not currently receive exhaust gas and has not yet received exhaust gas. As such, the particulate filter has not yet filtered or contacted any hydrocarbon-containing composition other than the composition used during the manufacturing process.

[0028] For example, the hydrocarbon-containing composition can be applied before the first use of a particle filter in the exhaust line of an internal combustion engine to filter particles from the exhaust gas flow of the internal combustion engine flowing in the exhaust line.Soot can also be formed before the start of intended use, or at the same time as its intended start of use.

[0029] According to various variant embodiments, an incomplete oxidation (for example an incomplete combustion) can be carried out after the particle filter has been positioned in the exhaust line of the internal combustion engine.

[0030] In this way, incomplete oxidation can be accomplished using the equipment of the exhaust line. For example, a gas having an oxidizing effect (e.g., oxygen) can be supplied to the particulate filter via the exhaust line, and the gaseous reaction products can be discharged via the exhaust line. The hydrocarbon-containing composition can also optionally be applied to the surface of the particulate filter after the particulate filter has been positioned in the exhaust line. The application of the hydrocarbon-containing composition applied to the particulate filter already arranged in the exhaust line can include spraying the hydrocarbon-containing composition directly onto the surface of the particulate filter.

[0031] According to various variant embodiments, by supplying a gas stream containing oxygen, it is possible to incompletely oxidize the hydrocarbonaceous composition. Thus, the hydrocarbonaceous composition reacts to produce carbon and water and optional by-products such as hydrocarbons and / or carbon monoxide.

[0032] An oxygen-containing exhaust gas stream from an internal combustion engine can be supplied, for example, as an oxygen-containing gas stream. To this end, the combustion air ratio of the internal combustion engine can be adjusted so that there is a slightly excess of oxygen for incomplete oxidation of the hydrocarbon-containing composition. The amount of oxygen supplied can be adjusted so that the oxidation is not completely carried out, because otherwise the hydrocarbon-linked carbon is converted into carbon dioxide instead of soot.

[0033] For example, in an internal combustion engine which is operated stoichiometrically or substoichiometrically with a combustion air ratio of λ≤1 during a coasting phase, oxygen which can be used for an incomplete oxidation of the hydrocarbon-containing composition can be fed through the exhaust line. Complete oxidation can be prevented here by extreme dissipation of heat in the particle filter. Furthermore, the oxygen supply during coasting can be limited in such a way that only incomplete oxidation takes place.

[0034] As part of the run-in calibration, it is further possible to run the internal combustion engine lean during initial operation (eg during the first kilometres), ie with a combustion air ratio of λ>1, so that incomplete oxidation of the hydrocarbon-containing composition is achieved or promoted.

[0035] Advantageously, an incomplete oxidation can therefore be carried out in the event of a start-up of the particulate filter of the internal combustion engine by supplying the exhaust gas flow of the internal combustion engine to the particulate filter previously provided with a hydrocarbon-containing composition.

[0036] According to a further variant embodiment, the hydrocarbon-containing composition can be applied before the particle filter is positioned in the exhaust line of the internal combustion engine. In this way, greater flexibility with regard to the application of the hydrocarbon-containing composition can be achieved. The hydrocarbon-containing composition can be applied, for example, during the production of the particle filter or when the particle filter is assembled in the housing.

[0037] According to various embodiment variants, the method may further comprise determining an optimum pore size and / or pore size distribution for a particle filter in an exhaust line in which the particle filter is to be arranged at a point in time after the end of a running-in period of the internal combustion engine, wherein soot formation is effected in such a way that the particle filter loaded with soot has an optimum pore size and / or pore size distribution.

[0038] In other words, it is initially determined which pore size and / or pore size distribution is more favorable for a specific particle filter after the running-in period has ended, for example by simulations known to those skilled in the art or by appropriate tests with particle filters of similar structure. In other words, the pore size and / or pore size distribution of the particle filter may increase the efficiency as high as possible without excessively increasing the exhaust back pressure. The tolerable exhaust back pressure may depend on one or more of the number of cylinders, the combustion process used, etc.

[0039] On the basis of this optimum pore size and / or pore size distribution, soot is then formed on the particle filter surface in such a way that if soot is formed at the same time as the start of the intended use, said optimum pore size and / or pore size distribution is present right from the start of the first intended use or before further intended use. In other words, the size of the pores of the particle filter is reduced by forming soot in such a way that an optimum pore size and / or pore size distribution is established. To this end, the amount of soot to be formed, the particle size of the soot and / or the particle size distribution of the soot can be varied as desired.

[0040] In this way, the optimum pore size and / or pore size distribution can be identified right from the start of the running-in period of the internal combustion engine, so that particulate pollutants can be effectively removed from the exhaust gas flow right from this stage onwards.

[0041] According to a further variant embodiment, organic compounds that can be easily applied in layers can be used, for example, as hydrocarbon-containing compositions. One possible example is a synthetic resin that can be applied in the form of a dispersion on the surface of a particle filter, as for example used to prime porous surfaces such as masonry before the actual coating. Water can be used, for example, as a dispersant, so that an aqueous synthetic resin dispersion is obtained.

[0042] In some examples, the synthetic resin dispersion may include finely divided synthetic resin particles that, after removal of the dispersant, may be deposited as a layer on the surface of the particulate filter, for example, by drying. The porosity of the layer can be adjusted by modifying the properties of the dispersion (e.g., solids content, particle size, or particle size distribution). The deposited synthetic resin particles may then be at least partially converted to soot via incomplete oxidation. Synthetic resins may be defined as resins (e.g., alkyd resins or acrylic resins) synthetically produced by polymerization, polyaddition, or polycondensation reactions.

[0043] In some embodiments, additionally or alternatively, the particulate filter may be a diesel particulate filter or a spark-ignition fuel particulate filter, for example, a particulate filter for a combustion engine running on motor gasoline. Since particulate emissions from a spark-ignition engine may be lower than particulate emissions from a diesel engine, it may take longer for the filter cake to accumulate, which results in adequate filtration and thus a longer run-in period. In particular for spark-ignition fuel particulate filters, the method according to the present disclosure therefore results in improved filter performance from the outset.

[0044] A particulate filter according to the present disclosure has a surface wherein at least a portion of the surface includes a hydrocarbon-containing composition.

[0045] The hydrocarbon-containing composition may be incompletely oxidized (eg, incompletely burned) to form soot. The soot layer may contribute to the filtering effect of the particulate filter and can improve the filter efficiency. Therefore, a larger pore size can be selected for the particulate filter, so that the exhaust back pressure can be reduced and fuel can be saved.

[0046] The particle filter can be produced, for example, by applying a hydrocarbon-containing composition to the surface of the particle filter as described above with respect to the method according to the present disclosure. The above explanation of the method according to the present disclosure is therefore also used to describe the particle filter according to the present disclosure. The advantages of the particle filter according to the present disclosure correspond to the advantages of the method according to the present disclosure and the corresponding variant embodiments of the present disclosure.

[0047] The particle filter according to the disclosure can be arranged or has been arranged, for example, in the exhaust line of an internal combustion engine and can be used for aftertreatment of an exhaust gas flow generated by the internal combustion engine, ie for filtering particulate components from the exhaust gas flow.

[0048] According to various variant embodiments, the hydrocarbon-containing composition may be formed and arranged on the surface of the particulate filter in such a way that the particulate filter has an optimal pore size and / or pore size distribution in the exhaust line in which the particulate filter is to be arranged at a point in time after an incomplete oxidation of the hydrocarbon-containing composition and after a run-in period of the internal combustion engine has ended.

[0049] In other words, it is initially determined which pore size and / or pore size distribution is more favorable for a specific particle filter after the running-in period has ended, for example by simulations known to those skilled in the art or by appropriate tests with particle filters of similar structure. In other words, the pore size and / or pore size distribution of the particle filter may increase the efficiency as high as possible without excessively increasing the exhaust back pressure. The tolerable exhaust back pressure may depend on one or more of the number of cylinders, the combustion process used, etc.

[0050] On the basis of this optimum pore size and / or pore size distribution, soot is then formed on the particle filter surface in such a way that if soot is formed at the same time as the start of the intended use, said optimum pore size and / or pore size distribution is present right from the start of the first intended use or before further intended use. In other words, the size of the pores of the particle filter is reduced by forming soot in such a way that an optimum pore size and / or pore size distribution is established. To this end, the amount of soot to be formed, the particle size of the soot and / or the particle size distribution of the soot can be varied as desired.

[0051] In some examples, additionally or alternatively, the carbon-containing composition may be a synthetic resin.

[0052] In some examples, the particulate filter may additionally or alternatively take the form of a diesel particulate filter or a spark ignition fuel particulate filter.

[0053] An engine arrangement according to the present disclosure comprises an internal combustion engine having an exhaust line for receiving an exhaust gas flow generated by the internal combustion engine, wherein a particulate filter according to the above description is arranged in the exhaust line.

[0054] The engine arrangement can be arranged in a vehicle, wherein a vehicle can be defined as any mobile means of transport, i.e., a land vehicle as well as a watercraft or an aircraft, such as a car. In one example, the engine is arranged in a hybrid vehicle (such as a Figure 1 Since the statutory regulations regarding the permissible emissions of atmospheric pollutants during operation of vehicles with internal combustion engines are becoming increasingly stringent, i.e. the limit values ​​to be observed are decreasing, the invention is particularly advantageous in this area because, firstly, the filtering out of particulate components from the exhaust gas flow can be improved right from the start of the running-in period. Secondly, for the situation after the end of the running-in period, the pore size and / or the pore size distribution can be optimized, so that problems caused by excessively high exhaust gas back pressures, such as increased fuel consumption, can be minimized.

[0055] Figure 1 Further shown is a particulate filter arranged in an exhaust passage of a vehicle, wherein the particulate filter can be adjusted to capture soot. The particulate filter can be composed of Figure 3 The curve diagram is used to represent Figure 3 Shown arranged in Figure 1 Increased efficiency of optimally sized and regulated particulate filters in vehicles. Figure 2 The efficiency of previous examples of particulate filters utilized in other vehicles is shown in the graph of for reference. Figure 4 Shows the amount of particulates released during a continuous emissions test. Figure 5 The diagram shows the method for adjusting the arrangement in Figure 1A method for a particulate filter in an exhaust system of an engine of a vehicle. The method may be directed to reducing a break-in period associated with previous examples of particulate filters. Figure 6 A method for forming a soot layer on a particulate filter disposed on a vehicle in response to back pressure is shown in FIG.

[0056] Figure 1 An example configuration with relative positioning of various components is shown. If shown as directly contacting or directly coupled to each other, then at least in one example, such elements may be referred to as directly contacting or directly coupled, respectively. Similarly, elements shown as being adjacent or adjacent to each other may be referred to as being adjacent or adjacent to each other, respectively, at least in one example. As an example, components placed in coplanar contact with each other may be referred to as coplanar contact. As another example, elements positioned separately from each other, with only space between them and no other components, may be referred to as such in at least one example. As another example, elements shown as being above / below each other, on opposite sides of each other, or on the left / right of each other may be referred to as such relative to each other. Further, as shown in the figure, in at least one example, the topmost element or point of an element may be referred to as the "top" of a component, and the bottommost element or point of an element may be referred to as the "bottom" of a component. As used herein, top / bottom, upper / lower, upper / lower may be relative to the vertical axis of the accompanying drawings and used to describe the positioning of the elements of the accompanying drawings relative to each other. Thus, in one example, an element shown as being above other elements is vertically positioned above other elements. As yet another example, the shapes of elements depicted within the drawings may be referred to as having those shapes (e.g., such as rounded, straight, planar, curved, rounded, chamfered, angled, etc.). Further, in at least one example, elements shown as intersecting one another may be referred to as intersecting elements or intersecting one another. Still further, in one example, elements shown as being within another element or shown as being outside another element may be referred to as such. It should be understood that one or more components referred to as "substantially similar and / or identical" may differ from one another based on manufacturing tolerances (e.g., within 1-5% deviation).

[0057] Figure 1An example of a cylinder of an internal combustion engine 10 included in an engine system 7 of a vehicle 5 is depicted. The engine 10 may be controlled at least in part by a control system including a controller 12 and input from a vehicle operator 130 via an input device 132. In this example, the input device 132 includes an accelerator pedal and a pedal position sensor 134 for generating a proportional pedal position signal PP. The cylinder 14 of the engine 10 (which may be referred to herein as a combustion chamber) may include combustion chamber walls 136, wherein a piston 138 is positioned in the combustion chamber walls 136. The piston 138 may be coupled to a crankshaft 140 so that reciprocating motion of the piston is converted into rotational motion of the crankshaft. The crankshaft 140 may be coupled to at least one drive wheel of the passenger vehicle via a transmission system. Further, a starter motor (not shown) may be coupled to the crankshaft 140 via a flywheel to enable a starting operation of the engine 10.

[0058] Cylinder 14 can receive intake air via a series of intake passages 142 , 144 , and 146 . Intake passage 146 can communicate with other cylinders of engine 10 in addition to cylinder 14 . Figure 1 Engine 10 is shown configured with a turbocharger 175 including a compressor 174 arranged between intake passages 142 and 144 and an exhaust turbine 176 arranged along exhaust passage 148. Compressor 174 may be at least partially powered by exhaust turbine 176 via shaft 180. A throttle 162 including a throttle plate 164 may be disposed along the intake passage of the engine for varying the flow rate and / or pressure of intake air provided to the engine cylinders. For example, throttle 162 may be positioned such as Figure 1 It is shown downstream of compressor 174 , but alternatively may be disposed upstream of compressor 174 .

[0059] In addition to cylinder 14, exhaust passage 148 can receive exhaust gas from other cylinders of engine 10. Exhaust gas sensor 128 is shown coupled to exhaust passage 148 upstream of emission control device 178. Sensor 128 can be selected from various suitable sensors for providing an indication of exhaust air-fuel ratio, such as a linear oxygen sensor or UEGO (universal or wide-range exhaust gas oxygen) sensor, a two-state oxygen sensor or EGO (as depicted) sensor, a HEGO (heated EGO) sensor, a NOx, HC or CO sensor. Emission control device 178 may be a three-way catalyst (TWC), a NOx trap, a particulate filter, various other emission control devices, or a combination thereof. In this article, emission control device 178 is a particulate filter shaped to capture soot from the exhaust gas flow. Particulate filter 178 may be porous and include one or more materials for capturing soot. In some examples, particulate filter 178 may be treated with pretreatment before being arranged in exhaust passage 148. Additionally or alternatively, injector 179 may be positioned to inject pretreatment onto or into particulate filter 178 in response to exhaust back pressure. Figure 1 In the example shown, injector 179 is positioned to inject into exhaust passage 148 upstream of particulate filter 178 .

[0060] Each cylinder of engine 10 may include one or more intake valves and one or more exhaust valves. For example, cylinder 14 is shown including at least one intake poppet valve 150 and at least one exhaust poppet valve 156 located at an upper region of cylinder 14. In some examples, each cylinder of engine 10 including cylinder 14 may include at least two intake poppet valves and at least two exhaust poppet valves located at an upper region of the cylinder.

[0061] Intake valve 150 may be controlled by controller 12 via actuator 152. Similarly, exhaust valve 156 may be controlled by controller 12 via actuator 154. During some conditions, controller 12 may vary the signals provided to actuators 152 and 154 to control the opening and closing of the respective intake and exhaust valves. The positions of intake valve 150 and exhaust valve 156 may be determined by respective valve position sensors (not shown). The valve actuators may be electric valve actuation type or cam actuation type or a combination thereof. The intake valve timing and the exhaust valve timing may be controlled simultaneously, or any possibility of variable intake cam timing, variable exhaust cam timing, dual independent variable cam timing or fixed cam timing may be used. Each cam actuation system may include one or more cams and may vary valve operation using one or more of a cam profile switching (CPS) system, a variable cam timing (VCT) system, a variable valve timing (VVT) system, and / or a variable valve lift (VVL) system operable by controller 12. For example, cylinder 14 may alternatively include an intake valve controlled via electric valve actuation and an exhaust valve controlled via cam actuation including CPS and / or VCT. In other examples, the intake and exhaust valves may be controlled by a common valve actuator or actuation system or a variable valve timing actuator or actuation system.

[0062] Cylinder 14 can have a compression ratio, which is the ratio of volumes when piston 138 is at bottom dead center and top dead center. In one example, the compression ratio is in the range of 9:1 to 10:1. However, in some examples using different fuels, the compression ratio may be increased. This may occur, for example, when using a higher octane fuel or a fuel with a higher latent heat of vaporization. If direct injection is used, the compression ratio may also be increased due to the effect of direct injection on engine knock.

[0063] In some examples, each cylinder of engine 10 may include a spark plug 192 for initiating combustion. Under select operating modes, ignition system 190 can provide an ignition spark to cylinder 14 via spark plug 192 in response to spark advance signal SA from controller 12. However, in some embodiments, spark plug 192 may be omitted, such as where engine 10 may initiate combustion via auto-ignition or via fuel injection, as is the case with some diesel engines.

[0064] In some examples, each cylinder of engine 10 may be configured with one or more fuel injectors for providing fuel thereto. As a non-limiting example, cylinder 14 is shown as including two fuel injectors 166 and 170. Fuel injectors 166 and 170 may be configured to deliver fuel received from fuel system 8. Fuel system 8 may include one or more fuel tanks, fuel pumps, and fuel rails. Fuel injector 166 is shown as being directly coupled to cylinder 14 for injecting fuel directly therein in proportion to the pulse width of signal FPW-1 received from controller 12 via electronic driver 168. In this manner, fuel injector 166 provides what is known as direct injection of fuel (hereinafter referred to as "DI") into combustion cylinder 14. Although Figure 1 Injector 166 is shown positioned to one side of cylinder 14, but may alternatively be located on top of the piston, such as near spark plug 192. Such a location may improve mixing and combustion when the engine is operated with alcohol-based fuels due to the lower volatility of some alcohol-based fuels. Alternatively, the injector may be located on top and near the intake valve to improve mixing. Fuel may be delivered to fuel injector 166 from a fuel tank of fuel system 8 via a high pressure fuel pump and a fuel rail. Further, the fuel tank may have a pressure transducer that provides a signal to controller 12.

[0065] Fuel injector 170 is shown arranged in intake passage 146 rather than in cylinder 14, in a configuration that provides what is known as port fuel injection (hereafter "PFI") into the intake port upstream of cylinder 14. Fuel injector 170 may inject fuel received from fuel system 8 in proportion to the pulse width of signal FPW-2 received from controller 12 via electronic driver 171. It should be noted that a single driver 168 or 171 may be used for both fuel injection systems, or multiple drivers may be used as depicted, such as driver 168 for fuel injector 166 and driver 171 for fuel injector 170.

[0066] In an alternative example, each of fuel injectors 166 and 170 may be configured as a direct fuel injector for injecting fuel directly into cylinder 14. In another example, each of fuel injectors 166 and 170 may be configured as a port fuel injector for injecting fuel upstream of intake valve 150. In other examples, cylinder 14 may include only a single fuel injector that is configured to receive different fuels from a fuel system in varying relative amounts as a fuel mixture and further configured to inject the fuel mixture directly into the cylinder as a direct fuel injector or directly upstream of the intake valve as a port fuel injector.

[0067] During a single cycle of the cylinder, fuel may be delivered to the cylinder by two injectors. For example, each injector may deliver a portion of the total fuel injection that is burned in cylinder 14. Further, the distribution and / or relative amount of the fuel delivered from each injector may vary with operating conditions such as described below (such as engine load, knock, and exhaust temperature). Port injected fuel may be delivered during an open intake valve event, during a closed intake valve event (e.g., substantially before the intake stroke), and during both an open intake valve operation and a closed intake valve operation. Similarly, direct injected fuel may be delivered during the intake stroke, and partially during the previous exhaust stroke, during the intake stroke, and partially during the compression stroke, for example. In this way, even for a single combustion event, the injected fuel may be injected at different timings from the port injector and the direct injector. In addition, for a single combustion event, multiple injections of the delivered fuel may be performed per cycle. Multiple injections may be performed during the compression stroke, the intake stroke, or any appropriate combination thereof.

[0068] The operation of the intake valve 150 may be described in more detail herein. For example, the intake valve 150 may be moved from a fully open position to a fully closed position, or to any position therebetween. All things being equal (e.g., throttle position, vehicle speed, pressure, etc.), the fully open position allows more air from the intake passage 146 to enter the cylinder 14 than any other position of the intake valve 150. Conversely, the fully closed position may prevent and / or allow a minimal amount of air from the intake passage 146 to enter the cylinder 14 than any other position of the intake valve 150. Thus, positions between the fully open position and the fully closed position may allow varying amounts of air to flow between the intake passage 146 and the cylinder 14. In one example, moving the intake valve 150 to a more open position allows more air to flow from the intake passage 146 to the cylinder 14 than its initial position.

[0069] Fuel injectors 166 and 170 may have different characteristics. These characteristics include differences in size, for example, one injector may have a larger injection hole than the other. Other differences include, but are not limited to, different injection angles, different operating temperatures, different targeting, different injection timing, different injection characteristics, different orientations, etc. In addition, depending on the distribution ratio of the injected fuel between injectors 170 and 166, different effects may be achieved.

[0070] The fuel tank in the fuel system 8 can hold fuels of different fuel types, such as fuels with different fuel qualities and different fuel compositions. These differences can include different alcohol content, different water content, different octane numbers, different vaporization heats, different fuel blends and / or combinations thereof, etc. An example of a fuel with different vaporization heats can include gasoline with a lower vaporization heat as a first fuel type, and ethanol with a larger vaporization heat as a second fuel type. In another example, the engine can use gasoline as a first fuel type and alcohol containing a fuel blend such as E85 (E85 is about 85% ethanol and 15% gasoline) or M85 (M85 is about 85% methanol and 15% gasoline) as a second fuel type. Other feasible substances include water, methanol, a mixture of alcohol and water, a mixture of water and methanol, a mixture of alcohol, etc.

[0071] The controller 12 Figure 1 1 is a microcomputer that includes a microprocessor unit 106, input / output ports 108, an electronic storage medium for executable programs and calibration values, shown in this particular example as a non-transitory read-only memory chip 110 for storing executable instructions, a random access memory 112, a keep alive memory 114, and a data bus. Controller 12 may receive various signals from sensors coupled to engine 10, including, in addition to those previously discussed, a measurement of intake mass air flow (MAF) from a mass air flow sensor 122; an engine coolant temperature (ECT) from a temperature sensor 116 coupled to a cooling sleeve 118; a surface ignition sensing signal (PIP) from a Hall effect sensor 120 (or other type) coupled to a crankshaft 140; a throttle position (TP) from a throttle position sensor; and an absolute manifold pressure signal (MAP) from sensor 124. An engine speed signal, RPM, may be generated by controller 12 from signal PIP. Manifold pressure signal MAP from a manifold pressure sensor may be used to provide an indication of vacuum, or pressure, in the intake manifold.Controller 12 may infer engine temperature based on the engine coolant temperature.

[0072] As mentioned above, Figure 1 Only one cylinder of a multi-cylinder engine is shown. As such, each cylinder may similarly include its own set of intake / exhaust valves, (one or more) fuel injectors, spark plugs, etc. It should be appreciated that engine 10 may include any suitable number of cylinders, including 2, 3, 4, 5, 6, 8, 10, 12, or more cylinders. Further, each of these cylinders may include reference cylinder 14 by Figure 1 Some or all of the various components described and depicted.

[0073] In some examples, the vehicle 5 may be a hybrid vehicle with multiple torque sources available to one or more wheels 55. In other examples, the vehicle 5 is a conventional vehicle with only an engine. In the example shown, the vehicle 5 includes an engine 10 and an electric machine 52. The electric machine 52 may be a motor or a motor / generator (M / G). When one or more clutches 56 are engaged, the crankshaft 140 of the engine 10 and the electric machine 52 are connected to the wheels 55 via a transmission 54. In the depicted example, the first clutch 56 is disposed between the crankshaft 140 and the electric machine 52, and the second clutch 56 is disposed between the electric machine 52 and the transmission 54. The controller 12 may send a signal to the actuator of each clutch 56 to engage or disengage the clutch so as to connect or disconnect the crankshaft 140 with the electric machine 52 and the components connected thereto, and / or connect or disconnect the electric machine 52 with the transmission 54 and the components connected thereto. The transmission 54 may be a gearbox, a planetary gear system, or another type of transmission. The powertrain system may be configured in various ways including as a parallel hybrid vehicle, a series hybrid vehicle, or a series-parallel hybrid vehicle.

[0074] The electric machine 52 receives power from the traction battery 58 to provide torque to the wheels 55. The electric machine 52 may also operate as a generator to provide power to charge the battery 58, such as during a braking operation.

[0075] The controller 12 receives the Figure 1 The signals of various sensors are used Figure 1 Various actuators adjust engine operation based on received signals and instructions stored in the controller's memory.

[0076] Now turn to Figure 2 , which shows a graph 200 showing the pore size distribution of a previous example of a particulate filter without pretreatment of a hydrocarbon-containing composition. This distribution is caused by the production process and may not be adjusted at will. That is, previous examples of particulate filters may experience variations in pore size, which may result in an extended run-in period and increased emissions.

[0077] Now turn to Figure 3 , which shows a graph 300 showing the change in pore size distribution after expected use of a particle filter (aged) compared to a new state. Using a particle filter reduces the frequency of large pores, which is the main reason for poor filtering results. In other words, the filter efficiency of an aged filter is significantly better than the filter efficiency in a new state. However, the pore size distribution of an aged particle filter cannot be directly established during production.

[0078] In other words, the new condition graph (solid line 302) shows the pore size for the particulate filter including the pretreatment with the hydrocarbon-containing composition. However, partial oxidation has not yet occurred, and the soot layer has not yet formed. The aged condition graph (dashed line 304) shows that the pore size has decreased, making the pore size distribution more evenly distributed. In addition, the pore size reduction can lead to an increase in particulate filter efficiency because more soot can be captured. Therefore, the pretreatment with the hydrocarbon-containing composition not only reduces the run-in period, but the pretreatment can be applied to at least a portion of the surface of the particulate filter to reduce the run-in period compared to the pretreatment. Figure 2 The previous example shown in generates a more uniform pore size distribution. The more uniform pore size distribution may result in the back pressure being maintained below a threshold back pressure such that engine operating parameters may not be affected by the back pressure while increasing the particulate filter efficiency.

[0079] Now turn to Figure 4 , which shows a graph 400 showing the results of six consecutive tests showing the improvement of filter efficiency during the expected use of the particulate filter, where the particulate filter is used in a vehicle such as Figure 1 The invention relates to a method for filtering particles from an exhaust gas flow of the internal combustion engine flowing in the exhaust gas line of a vehicle 5) in an exhaust gas line of an internal combustion engine of a vehicle 5). The vehicle speed is varied over time during the test and the cumulative number of particles that are not filtered out (i.e. detectable downstream of the particle filter in the exhaust gas line) is determined.

[0080] It is apparent that the cumulative number of released particles decreases from the first test 402 to the second test 404, to the third test 406, to the fourth test 408, to the fifth test 410, and to the sixth test 412. According to the present disclosure, in order to achieve sufficient filter performance right from the initial start-up (corresponding to test 1, graph 402), a pretreatment with a hydrocarbon-containing composition is applied to the surface of the particle filter before the first use of the particle filter, and soot is formed on the surface of the particle filter via incomplete oxidation of the hydrocarbon-containing composition. Soot is formed here in such a way that the particle filter loaded with soot has an optimal pore size distribution before the first use, so that for example according to the previously determined Figure 3 The “aged” pore size distribution.

[0081] It will be appreciated by one of ordinary skill in the art that placing a used particulate filter from a vehicle in the exhaust passage of the vehicle may not provide the same benefits of a particulate filter treated with a pretreatment having a hydrocarbon-containing composition. For example, the pore size distribution of a used particulate filter may not be tuned similarly to an unused particulate filter that received pretreatment. Furthermore, obtaining a used particulate filter may be expensive and unreliable because used particulate filters vary due to different previous driving conditions, etc. As such, pretreatment provides an inexpensive, reliable way to reduce the break-in period of a new, unused particulate filter.

[0082] Now turn to Figure 5 , which shows a method 500 for applying a pretreatment to an unused particulate filter and at least partially oxidizing the pretreatment, wherein the unused particulate filter is free of soot. The method 500 may be performed on the vehicle during the earliest (inaugural) ignition of the vehicle, or may be performed off-vehicle by a factory operation or the like. Instructions for performing the method 500 may be provided by a controller based on instructions stored on a memory of the controller and in conjunction with sensors received from the engine system (such as those referenced above). Figure 1 According to the method described below, the controller can use the engine actuators of the engine system to adjust the engine operation.

[0083] Method 500 begins at 502, which includes manufacturing a particulate filter including a first pore size distribution. In one example, the first pore size distribution may be substantially similar to that in Figure 3 The pore size distribution is shown in the new condition graph 302. As described above, the particulate filter may be a flow-through or wall particulate filter that includes one or more catalysts and / or other compounds for capturing and / or treating vehicle emissions.

[0084] In some examples, the first pore size distribution is a distribution in which a majority of pores are sized to be larger than a desired operational size. The desired operational size may be based on an optimal pore size for capturing soot from the exhaust. That is, a majority of pores may be sized to be larger, where the difference between the larger size and the optimal pore size is substantially equal to an expected size of a soot layer that will be formed after partial oxidation of the pretreatment applied to the particulate filter.

[0085] Method 500 may proceed to 504, which may include applying a pretreatment to at least a portion of the particulate filter. In some examples, the portion may include only a front surface of the particulate filter, wherein the front surface is a surface of the particulate filter that is a first surface for receiving exhaust gas. Additionally or alternatively, the pretreatment may be dispersed throughout the particulate filter, wherein the dispersion may be random or may be calculated, wherein the calculation is based on the formation of a soot layer of the pretreatment after partial oxidation. As described above, the pretreatment may be applied to the particulate filter on the vehicle (e.g., after the particulate filter is arranged in the exhaust passage) or outside the vehicle (before the particulate filter is arranged in the exhaust passage). If the pretreatment is applied on the vehicle, the controller may signal an actuator of the injector before or during initial ignition of the engine to inject the pretreatment toward or into the particulate filter. It should be understood that the injector may be a multi-purpose injector and may be positioned to inject other liquids and / or gases into the exhaust passage, including but not limited to a reductant for regenerating an aftertreatment device. If applied outside the vehicle, the pretreatment may be applied during the manufacture of the particulate filter or after the particulate filter is fully constructed. If applied during manufacturing, pre-treatment may be applied to the catalytic layer of the particulate filter.

[0086] In some examples, additionally or alternatively, the method may additionally include injecting pretreatment during vehicle conditions other than initial and / or first ignition. This may occur if a soot layer already present on the particulate filter is completely or over-oxidized so that the soot layer is less than a threshold soot layer. If the exhaust back pressure is less than a lower threshold back pressure, the soot layer may be less than the threshold soot layer. That is, if the exhaust back pressure is not high enough, the soot layer on the particulate filter may be too low, and the particulate filter efficiency may be less than the desired efficiency. In response, the injector may be activated to inject pretreatment. If regeneration (whether passive or active) is uncontrolled, over-oxidation may occur. In some examples, over-oxidation may further include degradation of the particulate filter, where the regeneration temperature is high due to excess oxygen, which may lead to cracks or leaks. In some examples, pretreatment may be applied to reduce the size of the cracks or leaks, thereby reducing emissions from the degraded particulate filter.

[0087] Method 500 may proceed to 506, which may include partially oxidizing the pretreatment to achieve a second pore size distribution. In one example, the second pore size distribution is substantially similar to Figure 3The second pore size distribution may be more evenly distributed than the first pore size distribution. In one example, the second pore size distribution may include more small pore sizes and fewer large pore sizes than the first pore size distribution. This may be a result of partial oxidation of the pre-treatment forming one or more soot layers that may at least partially shrink the pores of the particulate filter. In one example, as the pores shrink due to soot layer formation, the size of most pores may be set equal to the optimal pore size.

[0088] Partial oxidation may occur during an initial and / or first ignition. The first ignition may be defined as the first ignition of the engine following placement of the particulate filter in an exhaust line shaped to receive exhaust gas from the engine. As such, engine operating conditions may be adjusted during the first ignition to achieve an air-fuel ratio at or above stoichiometry such that partial oxidation may occur. The partial oxidation may be terminated once the exhaust backpressure is substantially equal to a threshold minimum backpressure. Terminating the partial oxidation may include reducing the air-fuel ratio to or below stoichiometry to reduce oxygen flow to the particulate filter. The threshold minimum backpressure may be equal to the backpressure sensed by the pressure sensor when the particulate filter includes a desired soot layer amount for increasing the efficiency of the particulate filter to a desired efficiency.

[0089] Now turn to Figure 6 , which shows a method 600 for on-board application of pre-treatment and partial oxidation of pre-treatment in response to sensed exhaust back pressure. Method 600 begins at 602, which includes determining, estimating, and / or measuring current engine operating parameters. Current engine operating parameters may include, but are not limited to, one or more of engine temperature, engine speed, manifold vacuum, exhaust gas recirculation flow rate, and air-fuel ratio.

[0090] Method 600 may proceed to 604, which may include estimating exhaust back pressure. In one example, from Figure 1 Feedback from the exhaust gas sensor 128 may be used to estimate exhaust back pressure.

[0091] Method 600 may proceed to 606, which may include determining whether the exhaust back pressure is less than a threshold minimum back pressure. As described above, the threshold minimum back pressure may correspond to a back pressure generated by a particulate filter including a desired soot layer, wherein the desired soot layer increases the efficiency of the particulate filter to a desired efficiency. The desired efficiency may be equal to the efficiency of the particulate filter after a break-in period.

[0092] If the backpressure is not less than the threshold minimum backpressure, method 600 may proceed to 608 to maintain current operating parameters and not apply pretreatment to the particulate filter. Additionally or alternatively, the air-fuel ratio may not be adjusted to at least partially oxidize pretreatment on the particulate filter.

[0093] If the backpressure is less than the threshold minimum backpressure, method 600 may proceed to 610 to determine whether pretreatment has been applied to the particulate filter. If the vehicle is equipped with an injector positioned to inject pretreatment onto and / or into the particulate filter, the method may determine whether pretreatment was recently applied (e.g., within a certain distance or within a certain duration). Data may be stored in a lookup table and may be collected from the lookup table. For example, if pretreatment was applied to the particulate filter 10 miles ago, it may be determined that pretreatment has been applied to the particulate filter. However, if pretreatment was applied to the particulate filter 1,000 miles ago, it may be determined that pretreatment will be applied to the particulate filter.

[0094] If it is determined that pretreatment has not been recently applied to the particulate filter, method 600 may proceed to 612 to apply pretreatment. This may include signaling an actuator of the injector to inject pretreatment. In one example, controller 12 may signal an actuator of injector 179 to inject a certain amount of pretreatment into the particulate filter. Figure 1 In one example, the amount of pre-treatment injected may be proportional to the difference between the threshold minimum back pressure and the sensed back pressure, where the amount increases as the difference increases. In some examples, additionally or alternatively, the amount may be fixed.

[0095] After 610 or 612, method 600 may proceed to 614, which may include adjusting engine operating parameters to partially oxidize the pretreatment. Partial oxidation of the pretreatment may include oxidation of the pretreatment including the hydrocarbon-containing composition, so that a soot layer is formed. Partial oxidation may be performed by causing excess air to flow to the particulate filter (which may include stoichiometric and / or lean air-fuel ratios) and / or may be performed by causing air to flow directly into the exhaust passage via a valve, etc. Overoxidation may be undesirable because it may reduce the amount of soot layer formed, thereby reducing the efficiency of the particulate filter. In this way, due to overoxidation and / or overregeneration of the particulate filter that may be caused by extended lean operation of the engine, the exhaust back pressure may drop below the threshold minimum back pressure. The soot layer may increase the efficiency of the particulate filter by reducing the pore size of the particulate filter pores to a desired size while additionally attracting soot from the exhaust flow.

[0096] Method 600 may proceed to 616, which may include determining whether the backpressure is equal to a threshold minimum backpressure. Once the backpressure is substantially equal to the threshold minimum backpressure, partial oxidation may be complete and the soot layer may be equal to a desired amount. If the backpressure is not equal to the threshold minimum backpressure, method 600 may proceed to 618 to continue partially oxidizing the pretreatment to continue forming the soot layer. If the backpressure is substantially equal to the threshold minimum backpressure, method 600 may proceed to 620 to adjust engine operating parameters to end oxidation of the pretreatment. This may include reducing the air-fuel ratio or adjusting other conditions to reduce air flow to the particulate filter. By doing so, the soot layer may remain intact, resulting in an optimal pore size for the particulate filter, increased efficiency in capturing soot and particulates from the exhaust, and a reduced run-in period relative to the previous example.

[0097] In this way, the break-in period of a particulate filter may be reduced by applying a pretreatment to the particulate filter. The pretreatment may be applied before or after the particulate filter is arranged in the exhaust passage of the vehicle. The pretreatment may include a hydrocarbon-containing composition that may form a soot layer when partially oxidized. The technical effect of applying the pretreatment to the particulate filter is to reduce the break-in period, which may reduce emissions. The pretreatment may further provide a reliable method of maintaining the particulate filter at at least a desired soot layer so that the efficiency of the particulate filter does not drop below a desired efficiency.

[0098] A method includes manufacturing a particulate filter; applying a hydrocarbon-containing composition to at least a portion of the particulate filter; arranging the particulate filter in an exhaust passage of a vehicle; and adjusting an engine operating parameter to incompletely oxidize the hydrocarbon-containing composition during a first combustion period of an engine of the vehicle. A first example of the method further includes wherein the incomplete oxidation includes an air-fuel ratio greater than or equal to stoichiometry. A second example of the method, optionally including the first example, further includes wherein the duration of the incomplete oxidation is terminated in response to a backpressure equal to at least a threshold minimum backpressure. A third example of the method, optionally including the first example and / or the second example, further includes wherein terminating the incomplete oxidation includes reducing the air-fuel ratio to at least slightly below stoichiometry. A fourth example of the method, optionally including one or more of the first to third examples, further includes wherein in anticipation of incomplete oxidation of the hydrocarbon-containing composition, the size of the pores of the particulate filter is slightly oversized relative to a desired operating pore size. A fifth example of the method, optionally including one or more of the first to fourth examples, further includes wherein the hydrocarbon-containing composition is a synthetic resin. A sixth example of the method, optionally including one or more of the first to fifth examples, further includes wherein the particulate filter is a diesel particulate filter or a spark ignition fuel particulate filter.

[0099] A method for pretreating a particulate filter, comprising: in response to an exhaust back pressure being less than a threshold minimum back pressure, applying a pretreatment comprising a hydrocarbon-containing composition to a portion of the particulate filter. A first example of the method further includes wherein the threshold minimum back pressure is equal to the back pressure generated by a minimum desired soot layer disposed on the particulate filter. A second example of the method, optionally including the first example, further includes wherein the pretreatment is applied to an unused particulate filter, wherein the unused particulate filter does not filter exhaust gas, and wherein the pretreatment is applied to a catalytic coating of the unused particulate filter. A third example of the method, optionally including the first example and / or the second example, further includes wherein the pretreatment is applied to an unused particulate filter in an exhaust passage of a vehicle or outside the exhaust passage. A fourth example of the method, optionally including one or more of the first to third examples, further includes wherein an injector is positioned to inject the pretreatment into the exhaust passage or directly into a particulate filter housing, wherein the injector injects the pretreatment during a first combustion of the engine after the particulate filter is installed in an exhaust passage shaped to receive exhaust gas from the engine. A fifth example of the method, which optionally includes one or more of the first to fourth examples, further includes wherein the injector is shaped to additionally inject a fluid other than the pretreatment, including one or more of water, urea, and fuel. A sixth example of the method, which optionally includes one or more of the first to fifth examples, further includes wherein the size of the plurality of pores of the particulate filter is set to a size greater than a desired pore size, wherein the desired pore size is based on an optimal size of the plurality of pores to capture particulates in the exhaust gas flow. A seventh example of the method, which optionally includes one or more of the first to sixth examples, further includes wherein the pretreatment is partially oxidized when the particulate filter first receives the exhaust gas.

[0100] A system comprising: a particulate filter treated with a pretreatment, comprising a pore size greater than a desired pore size, and wherein the particulate filter is free of soot and arranged in an exhaust passage shaped to receive exhaust gas from an engine; and a controller having computer readable instructions stored on its non-transitory memory, the computer readable instructions, when executed, enabling the controller to increase the air-fuel ratio to partially oxidize the pretreatment at a first ignition of the engine and to reduce the air-fuel ratio when the exhaust back pressure is equal to a threshold minimum back pressure. A first example of the system further includes wherein the pretreatment is a synthetic resin comprising a hydrocarbon-containing composition. A second example of the system, optionally including the first example, further includes wherein in response to the exhaust back pressure being equal to the threshold minimum back pressure, the pore size is equal to the desired pore size. A third example of the system, optionally including the first example and / or the second example, further includes wherein the particulate filter is treated with the pretreatment before or after the particulate filter is arranged in the exhaust passage. A fourth example of the system, optionally including one or more of the first to third examples, further includes wherein the partially oxidizing pretreatment further includes forming a soot layer on at least a portion of the particulate filter.

[0101] It should be noted that the example control and estimation procedures included herein can be used with various engine and / or vehicle system configurations. The control methods and procedures disclosed herein can be stored as executable instructions in a non-transitory memory and can be performed by a control system including a controller and various sensors, actuators and other engine hardware. The specific procedures described herein may represent one or more of any number of processing strategies, such as event-driven, interrupt-driven, multi-tasking, multi-threaded, etc. In this way, the various actions, operations and / or functions shown can be performed in the order shown, in parallel, or omitted in some cases. Similarly, the processing order is not necessary to achieve the features and advantages of the example embodiments described herein, but is provided for ease of illustration and description. One or more of the actions, operations and / or functions shown may be repeated depending on the specific strategy being used. Further, the actions, operations and / or functions can be graphically represented as codes in a non-transitory memory of a computer-readable storage medium to be programmed into an engine control system, wherein the actions are performed by executing instructions in a system including various engine hardware components and an electronic controller.

[0102] It should be understood that the configurations and procedures disclosed herein are exemplary in nature, and these specific embodiments are not to be considered limiting, as many variations are possible. For example, the above techniques can be applied to V-6, I-4, I-6, V-12, opposed 4, and other engine types. The subject matter of the present disclosure includes all novel and non-obvious combinations and sub-combinations of the various systems and configurations and other features, functions, and / or properties disclosed herein.

[0103] Unless otherwise specified, the term "about" as used herein should be interpreted to mean a range of ±5%.

[0104] The appended claims particularly point out certain combinations and subcombinations regarded as novel and non-obvious. These claims may refer to "an" element or "a first" element or their equivalent. Such claims should be understood to include incorporation of one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and subcombinations of the disclosed features, functions, elements, and / or properties may be claimed by amendment of the present claims or by presentation of new claims in this or a related application. Such claims, whether broader, narrower, the same, or different in scope to the original claims, are also deemed to be included in the subject matter of the present disclosure.

Claims

1. A method wherein include: manufacturing of particulate filters; applying a hydrocarbon-containing composition to at least a portion of the particulate filter; arranging the particulate filter in an exhaust passage of a vehicle; as well as adjusting engine operating parameters during a first combustion period of an engine of the vehicle to incompletely oxidize the hydrocarbon-containing composition; wherein the incomplete oxidation comprises an air-fuel ratio greater than or equal to stoichiometric; and Wherein the pore size of the particulate filter is slightly oversized relative to a desired operating pore size in anticipation of incomplete oxidation of the hydrocarbonaceous composition.

2. The method of claim 1, wherein the duration of the incomplete oxidation is terminated in response to a backpressure being equal to at least a threshold minimum backpressure.

3. The method of claim 2, wherein terminating the incomplete oxidation comprises reducing the air-fuel ratio to at least slightly below stoichiometry.

4. The method of claim 1, wherein the hydrocarbon-containing composition is a synthetic resin. 5 . The method of claim 1 , wherein the particulate filter is a diesel particulate filter or a spark ignition fuel particulate filter.

6. A method for pre-treating a particulate filter, wherein include: applying a pretreatment including a hydrocarbon-containing composition to a portion of the particulate filter in response to an exhaust backpressure being less than a threshold minimum backpressure; wherein when the particulate filter first receives exhaust gas, the pre-treatment is partially oxidized by adjusting an air-fuel ratio; and The method further includes setting a size of a plurality of pores of the particulate filter to a size greater than a desired pore size, wherein the desired pore size is based on an optimal size of the plurality of pores to capture particulates in an exhaust flow. 7 . The method of claim 6 , wherein the threshold minimum backpressure is equal to the backpressure generated by a minimum desired soot layer disposed on the particulate filter.

8. The method of claim 6, wherein the pretreatment is applied to an unused particulate filter, wherein the unused particulate filter does not filter exhaust gas, and wherein the pretreatment is applied to a catalytic coating of the unused particulate filter.

9. The method of claim 8, wherein the pretreatment is applied to the unused particulate filter in the exhaust passage of the vehicle or external to the exhaust passage.

10. The method of claim 6, wherein an injector is positioned to inject the pretreatment into an exhaust passage or directly into a particulate filter housing, wherein the injector injects the pretreatment during a first combustion of the engine after installing the particulate filter in an exhaust passage shaped to receive exhaust gas from the engine.

11. The method of claim 10, wherein the injector is configured to additionally inject a fluid other than the pretreatment, including one or more of water, urea, and fuel.

12. A system, wherein include: a particulate filter treated with a pretreatment having a hydrocarbon-containing composition, the particulate filter comprising a pore size that is greater than a desired pore size, and wherein the particulate filter is free of soot and disposed in an exhaust passage shaped to receive exhaust gas from an engine; as well as A controller having computer readable instructions stored on a non-transitory memory thereof, the computer readable instructions, when executed, enabling the controller to: increasing an air-fuel ratio upon a first ignition of the engine to partially oxidize the pretreatment; The air-fuel ratio is reduced when the exhaust back pressure is equal to a threshold minimum back pressure.

13. The system of claim 12, wherein the pretreatment is a synthetic resin comprising a hydrocarbon-containing composition.

14. The system of claim 12, wherein in response to the exhaust backpressure being equal to the threshold minimum backpressure, the orifice size is equal to the desired orifice size.

15. The system of claim 12, wherein the particulate filter is treated with the pre-treatment before or after the particulate filter is disposed in the exhaust passage.

16. The system of claim 12, wherein partially oxidizing the pretreatment further comprises forming a soot layer on at least a portion of the particulate filter.

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