Abstract: In the exhaust gas control system, the electronic control unit is configured to execute first air-fuel ratio control for controlling an air-fuel ratio of an air-fuel mixture in a part of cylinders to a lean air-fuel ratio and controlling an air-fuel ratio of an air-fuel mixture in the other part of the cylinders to a rich air-fuel ratio is executed. The electronic control unit is configured to execute second air-fuel ratio control to perform malfunction diagnosis. The electronic control unit is configured to execute second air-fuel ratio control when the execution of the first air-fuel ratio control is interrupted after the temperature of the three-way catalyst becomes equal to or higher than the diagnosis temperature.

Abstract: A method is provided for controlling nitrogen oxide emissions in the exhaust gas of an internal combustion engine by means of successive actuation of catalytic converters in the exhaust tract and of the internal combustion engine, wherein the catalytic converters or the internal combustion engine are actuated in succession if the actuation of a first device is not sufficient for reducing the nitrogen oxide emissions. An arrangement for carrying out the method is also provided.

Abstract: An exhaust system for an internal combustion engine, the exhaust system comprising, a lean NOx trap, a NOx storage and reduction zone on a wall flow monolithic substrate having a pre-coated porosity of 50% or greater, the NOx storage and reduction zone comprising a platinum group metal loaded on one or more first support, the or each first support comprising one or more alkaline earth metal compound, and a selective catalytic reduction zone on a monolithic substrate, the selective catalytic reduction zone comprising copper or iron loaded on a second support, the second support comprising a molecular sieve.

Abstract: An ignition system for an internal combustion engine includes a prechamber ignition device, a fuel admission valve for the prechamber ignition device, and a combustion consistency control mechanism configured to receive data indicative of at least one of a magnitude of a peak pressure in a combustion prechamber of the prechamber ignition device or a timing of the peak pressure in the combustion prechamber. The combustion consistency control mechanism calculates an error based on the data, and outputs a valve opening command to a fuel valve to produce a shot of combustion-initiating gases from the prechamber device, the valve opening command being based on the error.

Abstract: A variety of methods and arrangements for reducing noise, vibration and harshness (NVH) in a skip fire engine control system are described. In one aspect, a firing sequence is used to operate the engine in a skip fire manner. A smoothing torque is determined that is applied to a powertrain by an energy storage/release device. The smoothing torque is arranged to at least partially cancel out variation in torque generated by the skip fire firing sequence. Various methods, powertrain controllers, arrangements and computer software related to the above operations are also described.

Abstract: The invention provides a technique for more accurately executing failure diagnosis for an exhaust gas control apparatus having both a selective reduction function and a filter function. To this end, a failure diagnosis apparatus according to the invention for the exhaust gas control apparatus having both the selective reduction function and the filter function computes a NOx purification rate pertaining to a case where the exhaust gas control apparatus is normal based on an estimated value of the amount of particulate matter (PM) collected or accumulated in the exhaust gas control apparatus and an estimated value of the NO2 ratio of exhaust gas flowing into the exhaust gas control apparatus, and determines that the exhaust gas control apparatus fails when the difference between the result of the calculation and an actual NOx purification rate exceeds a threshold.

Abstract: Methods and systems are provided for controlling individual cylinder air-fuel ratio (AFR) in a combustion engine. In one example, a method may include measuring a high-frequency exhaust gas composition, parsing the measured high-frequency exhaust gas composition to determine a first cylinder-specific component of the high-frequency exhaust gas composition, estimating an air-fuel ratio (AFR) based on the first cylinder-specific component of the measured high-frequency exhaust gas composition, and correcting the estimated AFR by subtracting intercylinder exhaust gas interactions from the estimated AFR.

Abstract: An exhaust gas aftertreatment unit includes a selective catalytic reduction device that treats engine exhaust gas, a connecting pipe that guides the engine exhaust gas to the reduction device, a reducing agent injection device disposed on the connecting pipe to inject a reducing agent into the exhaust gas, and a cooling water flowpath that guides cooling water to an internal flowpath of the injection device. The cooling water path includes a first flowpath joined with the internal flowpath, second and third flowpaths branching off from the first flowpath, and a branching point where the first flowpath branches into the second flowpath and the third flowpath is positioned higher than a connecting portion of the injection device and the first flowpath. The third flowpath extends further upward than the second flowpath from the branching point. The second and third flowpaths merge on an opposite side of the branching point.

Abstract: A method is disclosed for controlling an injector for injecting a reductant into a selective catalytic reduction system of an internal combustion engine. A value of a concentration of nitrogen-oxides in the exhaust gas aftertreatment system downstream of the selective catalytic reduction system is measured, and a first difference is calculated between the measured value of the nitrogen-oxides concentration and a predetermined reference value thereof. A value of a concentration of ammonia in the exhaust gas aftertreatment system downstream of the selective catalytic reduction system is measured, and a second difference is calculated between the measured value of the ammonia concentration and a predetermined reference value thereof. A quantity of reductant to be injected by the injector is calculated as a function of the calculated first difference and second difference, and the injector is operated to inject the calculated quantity of reductant.

Abstract: Methods and systems are provided for integrating engine water injection technology with a CVT transmission. Responsive to a driver demand, a controller may determine whether to maintain a current water injection state or transition to an alternate water injection state based on each of the efficiency of the transition, water availability, and any engine limitations that may be incurred at the engine speed-load following the transition. To improve the net fuel economy benefit while addressing the engine limitation, the water injection state transition may be combined with a CVT adjusted engine speed-load regime, while maintaining engine power output.

Abstract: An exhaust gas purifying apparatus for an internal combustion engine, in which a NOx absorbing catalyst and a NOx concentration sensor for detecting a NOx concentration in exhaust gases of the engine, are provided in an exhaust passage of the engine. A rich spike for temporarily enriching the air-fuel ratio is performed, and an execution timing of the rich spike is determined based on a detected output from the NOx concentration sensor. Performing the rich spike is determined to be unnecessary during a reducing state period from the time the rich spike ends to the time a preset time period has elapsed, and is also determined to be unnecessary when a change tendency of the detected output is determined to be an output decreasing state where the detected output is decreasing.

Abstract: The sulfur oxides detection system includes a device part comprising a first electrochemical cell having a first solid electrolyte layer, a first electrode, and a second electrode; and a diffusion regulating layer. A power supply supplying voltage is provided between the electrodes as well as a detector detecting a first current correlation parameter, and a control part controlling the power supply and acquiring the first current correlation parameter. The control part controls the power supply so that a first voltage is applied between the electrodes and calculates a concentration of sulfur oxides in the measured gas based on the first current correlation parameter detected by the detector when the first voltage is applied between the electrodes, but it does not calculate the concentration of sulfur oxides in the measured gas when it judges that a concentration of water in the measured gas is not stable.

Abstract: A method of operating an internal combustion engine having a turbocharger for pressurizing an intake airflow and an after-treatment (AT) system including an AT device for reducing nitrogen oxides (NOX) concentration in the engine exhaust gas. The method includes operating the engine with a variable high-pressure exhaust gas recirculation (EGR) and low-pressure EGR split in the intake airflow. The method also includes determining the NOX concentration in the exhaust gas and determining a current high-pressure EGR to low-pressure EGR split in the intake airflow. The method additionally includes determining an EGR corrective factor using the determined current high-pressure EGR to low-pressure EGR split and applying the determined EGR corrective factor to the determined NOX concentration to generate a corrected NOX concentration. Furthermore, the method includes regulating operation of the AT system to treat the exhaust gas via the AT device in response to the generated corrected NOX concentration.

Abstract: In the case of a method for operating an exhaust gas aftertreatment system of a motor vehicle, the exhaust gas aftertreatment system comprises at least one NOx storage catalyst (10) and at least one SCR catalyst (30). According to the invention, when an inadequate function of the NOx storage catalyst (10) or of the SCR catalyst (30) is identified, at least one auxiliary measure is initiated which leads to a reduction of the NOx emissions of the motor vehicle.

Abstract: Apparatus for reactivating a sulfur poisoned oxidation catalyst operating in exhaust of a lean burn, methane source fueled combustion device. Reactivation includes desulfation of the poisoned catalyst through a CO supplementation apparatus communicating with the control unit that is adapted to supplement CO content in exhaust reaching the catalyst, while avoiding an overall rich exhaust atmosphere at the catalyst (e.g., an added supply of hydrocarbons to one or more-of the lean burn engine's combustion chambers as by an ECU controlled extra supply of NG to some of the combustion chambers). Also featured is a method for desulfation of an oxidation catalyst of a lean burn CNG engine by supplying excess CO to exhaust reaching the catalyst while retaining an overall lean state, and a method of assembling an apparatus for reactivating a sulfur deactivated lean burn NG engine catalyst by assembling a CO supplementation apparatus with control unit.

Abstract: An apparatus according to the present invention is adapted to calculate an NOX storage rate defined as the rate of the quantity of NOX stored into the NSR catalyst to the quantity of NOX flowing into the NSR catalyst, based on quantity of NOX flowing into the NSR catalyst and the quantity of NOX flowing out of the NSR catalyst in a state in which the amount of NOX stored in the NSR catalyst is equal to or larger than the breakthrough start amount of a criterion catalyst and the flow rate of exhaust gas flowing through the NSR catalyst is equal to or higher than a predetermined lower limit flow rate. The apparatus diagnoses the NSR catalyst as normal if the NOX storage rate thus calculated is equal to or higher than a predetermined threshold and as abnormal if the NOX storage rate is lower than the predetermined threshold.

Abstract: A catalyst article comprises an SCR catalyst and a NOx adsorber catalyst, where each of these catalysts comprise a metal molecular sieve, each with a different metal. The catalyst article can be close coupled with other components to give a NOX performance advantage from cold start to a combined DOC and SCRF system. Higher NOX conversion is also shown in under-floor location due to NOx storage before SCR light off and selective NH3 slip control, allowing higher NH3 fill levels. Systems comprising the catalyst article and methods of using the catalyst article to give improved hydrocarbon and carbon monoxide control, as well as ammonia slip control, are described. The systems can include flow-through or wall-flow monoliths.

Abstract: Disclosed are model predictive control (MPC) systems, methods for using such MPC systems, and motor vehicles with selective catalytic reduction (SCR) employing MPC control. An SCR-regulating MPC control system is disclosed that includes an NOx sensor for detecting nitrogen oxide (NOx) input received by the SCR system, catalyst NOx sensors for detecting NOx output for two SCR catalysts, and catalyst NH3 sensors for detecting ammonia (NH3) slip for each SCR catalyst. The MPC system also includes a control unit programmed to: receive desired can conversion efficiencies for the SCR catalysts; determine desired can NOx outputs for the SCR catalysts; determine maximum NH3 storage capacities for the SCR catalyst; calculate the current can conversion efficiency for each SCR catalyst; calculate an optimized reductant pulse-width and/or volume from the current can conversion efficiencies; and, command an SCR dosing injector to inject a reductant into an SCR conduit based on the calculated pulse-width/volume.

Abstract: An internal combustion engine comprises an exhaust purification catalyst. The control system comprises a temperature detecting means for detecting or estimating a temperature of the exhaust purification catalyst, performs feedback control so that an air-fuel ratio of exhaust gas flowing into the exhaust purification catalyst becomes a target air-fuel ratio, and performs target air-fuel ratio setting control which alternately sets the target air-fuel ratio to a rich set air-fuel ratio and a lean set air-fuel ratio. In addition, the control system increases a variation difference, obtained by subtracting a rich degree of the rich set air-fuel ratio from a lean degree of a lean set air-fuel ratio, when a temperature of the exhaust purification catalyst detected or estimated by the temperature detecting means is a predetermined upper limit temperature or less compared with when it is higher than the upper limit temperature.

Abstract: Provided are methods for warming up a vehicle exhaust treatment system prior to an engine start, wherein the vehicle includes an internal combustion engine (ICE), a supercharger capable of delivering air to an ICE intake, an exhaust gas treatment system including an exhaust gas treatment device and an upstream electric heating device and capable of accepting exhaust gas from the ICE, and optionally a turbocharger having a turbine in fluid communication with the exhaust gas treatment system. Methods include establishing fluid communication between the supercharger and the exhaust gas treatment system, engaging the supercharger to communicate air to the exhaust gas treatment system via the supercharger, and engaging the heating device. The method can further comprise reducing turbine resistance by reducing the power position of the turbine or opening a wastegate. The methods can further include first satisfying a start condition, and/or subsequently detecting a termination condition.

Abstract: A diesel engine includes an exhaust-gas purification device and allows the exhaust-gas purification device to be disposed at the upper face side of the diesel engine. The exhaust-gas purification device purifies exhaust gas discharged from the diesel engine. The direction of a long side of the exhaust-gas purification device is perpendicular to the direction in which a crankshaft, included in the diesel engine, extends. An exhaust throttle device is disposed between an exhaust manifold, included in the diesel engine, and an exhaust gas inlet, included in the exhaust-gas purification device.

Abstract: A reciprocating internal combustion engine with an emission control device and a method for operating same are described. At least one throttle, arranged on the intake side, at least one main fuel injection nozzle for feeding a main fuel to a combustion chamber of the diesel engine, and at least one catalytic converter are arranged in the center of an exhaust gas passage for conducting exhaust gas out of the combustion chamber, and at least one control device is used. A soot burn-off rate determined according to a model approach is maximized using a regulation process by means of a throttle valve.

Abstract: A method for diagnosing NOx sensors in an exhaust aftertreatment system includes suspending reductant dosing in an exhaust aftertreatment system; purging a reductant deposit in a selective catalytic reduction (SCR) system of the exhaust aftertreatment system; adjusting at least one of an ignition timing and an engine speed for an engine to adjust an engine out nitrogen oxide (NOx) amount; receiving measured SCR inlet NOx data from a SCR inlet NOx sensor and measured SCR outlet NOx data from a SCR outlet NOx sensor; determining a phase shift between the measured SCR inlet and SCR outlet NOx data; applying the determined phase shift to the SCR outlet NOx data; and determining a diagnostic feature based on the SCR inlet NOx data and the phase shifted SCR outlet NOx data regarding a state of the SCR inlet and outlet NOx sensors.

Abstract: A method for monitoring thermal events in an aircraft engine compartment includes obtaining first sensor data from a first sensor located within an engine compartment of an aircraft. The method also includes determining a time series moving average based at least in part on a subset of the first sensor data. The time series moving average is indicative of an average temperature rate-of-change of the engine compartment. The method further includes determining a standard deviation of the time series moving average and detecting a trend of temperature rates-of-change that satisfy a rate-of-change criterion. The rate-of-change criterion is based on a multiple of the standard deviation, and the temperature rates-of-change are based on temperatures of the engine compartment. The method also includes generating an alert in response to detecting the trend. The alert is indicative of a thermal event associated with the engine compartment.

Abstract: An internal combustion engine comprises an exhaust purification catalyst arranged in an exhaust passage of the internal combustion engine; an upstream side air-fuel ratio sensor for detecting an air-fuel ratio of exhaust gas flowing into the exhaust purification catalyst; and a downstream side air-fuel ratio sensor for detecting an air-fuel ratio of exhaust gas flowing out from the exhaust purification catalyst. An abnormality diagnosis system of air-fuel ratio sensors judges that at least one of the air-fuel ratio sensors has become abnormal when a difference or ratio between an output value of said upstream side air-fuel ratio sensor and an output value of said downstream side air-fuel ratio sensor becomes outside a predetermined range of normal difference or predetermined range of normal ratio during atmospheric gas introduction control where the exhaust gas flowing into the exhaust purification catalyst becomes atmospheric gas.

Abstract: Methods and systems are provided for detecting ammonia slip from a catalytic converter. In one example, a method may include recirculating exhaust gas containing ammonia and measuring only a NOx concentration of the recirculated exhaust gas following its combustion.

Abstract: The present invention discloses a novel apparatus and methods for augmenting the power of a gas turbine engine, improving gas turbine engine operation, and reducing the response time necessary to meet changing demands of a power plant. Improvements in power augmentation and engine operation include additional heated compressed air injection, steam injection, water recovery, exhaust tempering, fuel heating, and stored heated air injection.

Abstract: In a method for operating an SCR catalytic converter system of an internal combustion engine, the SCR catalytic converter system comprises at least one SCR catalytic converter (30) and at least one upstream SCR-coated particulate filter (20). In order to inject liquid reducing agent for the SCR catalytic converter (30) and/or for the SCR-coated particulate filter (20), a first injection position is provided upstream of the SCR-coated particulate filter (20) in the form of a first metering device (40) and a second injection position is provided upstream of the SCR catalytic converter (30) and downstream of the SCR-coated particulate filter (20) in the form of a second metering device (50). The injection positions for the injection of liquid reducing agent are selected in a manner which is dependent on the operating states of the SCR catalytic converter system.

Abstract: An exhaust gas purification system capable of preventing clogging of a reducing agent injection valve due to solidified urea aqueous solution to prevent a decrease in the exhaust gas purification efficiency of an internal-combustion engine. The exhaust gas purification system includes a diesel particulate filter, a reducing agent injection valve and an SCR catalyst in this order from the exhaust upstream side. A condition satisfaction determination section determines whether or not urea aqueous solution is likely to be solidified when detecting that an ignition switch is turned off, and an internal-combustion engine stop prevention section prevents the internal-combustion engine from being stopped, based on a determination by the condition satisfaction determination section.

Abstract: A PCV valve that ventilates a crankcase is provided. A three-way catalyst and a NOx storage/reduction catalyst are provided in an exhaust passage. An electronic control unit performs a stoichiometric control and a lean control. When a crankcase ventilation request is issued, a relationship between a ventilation amount of ventilation achieved by the PCV valve and a fuel consumption resulting from the ventilation is calculated. Furthermore, an operational condition under which the ventilation amount meets a required ventilation amount and the fuel consumption is minimized is calculated. The operational condition is calculated so that a constant engine torque is maintained and the air-fuel ratio falls within a range that ensures purification.

Abstract: A computer program, system and method are provided for thermally regulating an injector injecting a reducing agent into an exhaust pipe of an internal combustion engine. A pump is activated to deliver a coolant in a coolant circuit having a portion in heat exchange relation with the injector. A value is determined for a mass flow rate of the coolant delivered by the pump. A value is calculated for a temperature of the injector as a function of the determined value of the mass flow rate. A difference is calculated between the calculated value of the injector temperature and a predetermined set-point value thereof, and the mass flow rate of the coolant delivered by the pump is adjusted on the basis of the calculated difference.

Abstract: A method and apparatus for cleaning up a particulate filter of an internal combustion engine is provided. The internal combustion engine is operated to regenerate the particulate filter measuring. During the regeneration, a value of an engine speed is determined. A temperature of the particulate filter is controlled, if the measured value of the engine speed is smaller than or equal to a predetermined threshold value thereof. The particulate filter temperature is controlled by boosting the internal combustion engine and supplying the internal combustion engine with an amount of recirculated exhaust gases.

Abstract: A system for producing an ion concentration gradient and a temperature-responsive electrolyte material which are utilizable, for example, for efficiently converting heat energy that has been discarded into reusable energy or for efficiently recovering an acid gas, such as carbon dioxide is provided. A temperature-responsive electrolyte is used to produce an ion concentration gradient by means of a temperature gradient. The temperature-responsive electrolyte is used in the state of an aqueous solution and also in the state of a solid phase.

Abstract: An abnormality diagnostic device for an engine is provided. The abnormality diagnostic device includes an ECU that is configured to execute a temperature rise process so as to raise a temperature of a catalyst. The ECU is configured to determine whether the engine is in an abnormal state. The ECU is configured to store the following values (i) to (iv) in the abnormal state: (i) a speed of the engine, (ii) a load of the engine, (iii) a coolant temperature, (iv) an execution state indicative of whether the temperature rise process is executed. The ECU is configured to determine whether the engine has recovered from the abnormal state to a normal state based on a current speed of the engine, a current load of the engine, a current coolant temperature, and a current execution state of the temperature rise process.

Abstract: A radio frequency sensing, control, and particulate matter diagnostics network and system and method and, more specifically, a radio frequency particulate filter diagnostics system comprising a housing including an inlet connected to a source of particulate matter, a particulate filter in the housing and adapted for filtering the particulate matter, and a radio frequency sensor adapted to detect conditions of abnormal particulate filter or system operation and including at least one radio frequency probe configured to be in contact with the housing for the particulate filter housing and adapted to receive radio frequency signals and a radio frequency control unit in communication with the radio frequency probe.

Abstract: A system includes a first diesel engine operable to drive a first device, a first DEF tank associated with the first engine and operable to provide DEF to the first diesel engine during operation, a second diesel engine operable to drive a second device, and a second DEF tank associated with the second engine and operable to provide DEF to the second diesel engine during operation. An external DEF tank is arranged to contain a quantity of DEF that is coupled to the first DEF tank and the second DEF tank and operable to selectively deliver DEF from the external DEF tank to each of the first DEF tank and the second DEF tank.

Abstract: A method for operating a motor vehicle is disclosed. The motor vehicle is provided with a hybrid drive device having an electric machine, an internal combustion engine and a particle filter associated with the internal combustion engine, wherein the internal combustion engine is operated temporarily for regenerating the particle filter. In a first operating mode, the regeneration is only started when it is determined by a navigation device that an electric driving region to be driven through lies ahead, in which region an operation of the internal combustion engine and/or the regeneration of the particle filter is not desired.

Abstract: An exhaust aftertreatment system including a selective catalytic reduction device (SCR), a NOx sensor and a reductant injection system is described. A method for controlling the reductant injection system to inject reductant into the exhaust gas feedstream upstream relative to the SCR includes monitoring engine operation, and determining an initial reductant dosing rate responsive to the engine operation. A dosing perturbation is induced in the reductant dosing rate. The exhaust gas feedstream is monitored via the NOx sensor, and a reductant dosing correction term is determined based upon the monitoring. A final dosing rate for controlling the reductant injection system is determined based upon the initial reductant dosing rate, the dosing perturbation, and the reductant dosing correction term.

Abstract: A reagent dosing system for dosing a reagent into the exhaust gas stream of an internal combustion engine includes a reagent tank for storing a supply of reagent; an injector module including an atomizing dispenser and a positive-displacement metering pump which draws reagent from the reagent tank and delivers it to the dispenser; a supply line coupling the reagent tank to the injector module; a dosing control unit operable to control the injector module to inject reagent into the exhaust gas stream; and an additional priming pump arranged, in use, to urge reagent along the supply line toward the injector module under selected conditions.

Abstract: In a multiple cylinder supercharged engine, when reduced cylinder operation is executed, a throttle, which is located downstream of a compressor driven by a turbine provided in an exhaust passage, through which exhaust gas of a cylinder group flows, is operated to a fully closed state, wherein the reduced cylinder operation is applied to the cylinder group. A fuel injection amount of at least one cylinder included in the cylinder group is made smaller than a fuel injection amount of a cylinder included in another cylinder group, and this at least one cylinder is operated, in order to increase rotational speed of the compressor, so that a value of pressure of an upstream side of the throttle is controlled to a value, which is equal to or larger than a value of pressure of a downstream side of the throttle.

Abstract: An emission control system for an engine is described herein. The emission control system includes a reductant injector extending into an exhaust conduit upstream of a catalyst, the reductant injector including a reductant passage receiving reductant from a reductant reservoir and a first exhaust gas inlet receiving exhaust gas from the exhaust conduit, a boundary of the first exhaust gas inlet at least partially delineated by an inlet wall extending into an interior exhaust passage from an outer housing surface, the interior exhaust passage adjacent to the reductant passage and receiving exhaust gas from the first exhaust gas inlet and fluidly separated from the reductant passage.

Abstract: A system for diagnosing a sensor of an exhaust aftertreatment system may include receiving a first tank level value from a sensor. A plurality of reductant dosing command values over a period of time are received. A dosed reductant value is determined responsive to the plurality of reductant dosing command values reaching a threshold integrated value. A second tank level value is received from the sensor responsive to the dosed reductant value reaching the threshold integrated value. A sensor-estimated dosing value is determined based on the difference between the first tank level value and the second tank level value. The sensor may be diagnosed as performing outside of an acceptable calibration range based on the difference between the sensor-estimated dosing value and the dosed reductant value.

Abstract: A method for correcting an air-fuel ratio deviation for each cylinder in an engine of a vehicle includes measuring a signal of an oxygen sensor mounted on an exhaust pipe of the vehicle using a low-pass filter and a moving-average filter; calculating an oxygen sensor roughness based on the measured signal of the oxygen sensor modulating a fuel injection amount of fuel injected into each cylinder in the engine; detecting a variation of the oxygen sensor roughness according to the modulated fuel injection amount; determining an optimal fuel injection amount based on a relationship between the fuel injection amount and the oxygen sensor roughness; performing fuel injection amount control based on the determined optimal fuel injection amount to correct the air-fuel ratio deviation for each cylinder.

Abstract: A method and device for monitoring the formation of nitrogen dioxide at an oxidation catalytic converter is disclosed. The conversion of the nitrogen oxides, corresponding to a first exhaust gas volume flowrate through the oxidation catalytic converter, is detected. The exhaust gas volume flowrate is then changed and the conversion of the nitrogen oxides which changes with the change in the exhaust gas volume flowrate is also detected. By reference to the respective conversion of the nitrogen oxides at the different exhaust gas flowrates through the oxidation catalytic converter, it is concluded, on the basis of a predetermined relationship between the conversion of the nitrogen oxides and a proportion of nitrogen dioxide in the nitrogen oxides in the exhaust gas, that nitrogen dioxide is being formed at the oxidation catalytic converter.

Abstract: A method of regenerating a selective catalytic reduction catalyst on a diesel particulate filter (SDPF) includes predicting a reducing agent amount oxidized in the SDPF during regeneration of the SDPF if the regeneration of the SDPF is necessary; calculating a quantity of heat generated from the reducing agent amount oxidized in the SDPF; calculating a temperature change from the generated quantity of heat; calculating a target temperature when regenerating the SDPF; and performing the regeneration according to the target temperature.

Abstract: A selective catalytic reduction system includes a selective catalytic reduction device on an exhaust pipe of an engine, a urea solution tank that stores a urea solution, a float-type urea solution level sensor in the urea solution tank, a dosing valve on the exhaust pipe upstream of the selective catalytic reduction device, a urea solution injection control section that controls an amount of urea solution to be injected through the dosing valve in accordance with an amount of NOx discharged from the engine, an inclination sensor that detects an inclination angle of the urea solution tank relative to horizontal, and an inclination angle correcting section that corrects a liquid level of the urea solution, the liquid level being detected by a detection unit from the position of a float, with the inclination angle detected by the inclination sensor.

Abstract: A method of controlling engine internal exhaust gas recirculation may include estimating a flow restriction through a diesel particulate filter in an exhaust system of an engine assembly and adjusting a backpressure control valve in the exhaust system downstream of the diesel particulate filter based on the flow restriction. A controlled amount of internal exhaust gas recirculation may be provided to the engine assembly based on adjusting the backpressure control valve.

Abstract: A rich control for temporarily declining an air-fuel ratio of exhaust gas discharged from an engine combustion chamber is performed by an additional fuel being injected into a cylinder in an expansion stroke or an exhaust stroke in a state where a throttle opening degree is switched from a base throttle opening degree to a throttle opening degree for the rich control and an EGR rate is switched from a base EGR rate to an EGR rate for the rich control. The rich control is initiated by switching a low pressure side EGR control valve opening degree (VEGRL) to a low pressure side EGR control valve opening degree for the rich control (VEGRLR), then switching a high pressure side EGR control valve opening degree (VEGRH) to a high pressure side EGR control valve opening degree for the rich control (VEGRHR), then controlling the throttle opening degree (VTH), and then initiating the injection of the additional fuel (Qa).

Abstract: A system and related method for controlling reductant dosing in a selective catalyst reduction system includes a chamber containing a catalyst, and a controllable reductant dosing system that includes a controllable injector connected to a reservoir of reductant, and a controller that obtains inlet exhaust temperature, speed, and composition information, for example, from one or more sensors in the exhaust stream. The controller solves a set of coupled equations comprising (i) one-dimensional, steady ammonia mass balance equations and (ii) one-dimensional, steady species mass transfer equations, to calculate a one-dimensional distribution of ammonia storage in the catalyst and a one-dimensional distribution of exhaust species concentrations through the SCR system including a concentration of ammonia and a concentration of one or more nitrogen oxides at the SCR outlet; and uses the solution to control the injector. The method has been found to anticipate ammonia and NOx slip.

Abstract: A control device of an internal combustion engine is configured to perform a fuel cut-off control and an abnormality diagnosis control. A heating device for heating an element of an air-fuel ratio sensor is controlled by making an element temperature of the air-fuel ratio sensor become a target element temperature. The target element temperature of the air-fuel ratio sensor during a high temperature control period from a time when a prescribed high temperature control begins after a start of the internal combustion engine to a time when the prescribed high temperature control is completed after completion of the abnormality diagnosis control of the air-fuel ratio sensor is set to be higher than the target element temperature outside the high temperature control period.