Abstract: A method and system for controlling hydrocarbon injection into engine exhaust to reduce NOx. The method and system inject the hydrocarbon into the engine exhaust in accordance with detection of a light-off event. The light-off event can be detected because when there is this hydrocarbon-O2 reaction, such reaction is an exothermic reaction and thus heat is generated and given off. The generation of such heat may be detected by measuring the difference in temperature across the catalyst. The peak in NOx conversion efficiency temperature changes with age. However, because the peak in NOx conversion efficiency temperature occurs at substantially the same light-off temperature, a determination of light-off by the system and method enables adjustment in the hydrocarbon injection level for maximum NOx reduction efficiency.

Abstract: A method wherein a reactant is added to a substance to react with such substance. The product of such reaction along with un-reacted portions of the substance and un-reacted portions of the reactant are directed to a sensor. The sensor produces an output signal in response to detection of both the un-reacted portions of the substance and the un-reacted portions of the reactant. The method includes changing the amount of reactant added to the substance. A measurement is made to determine whether the change in the amount of reactant and the change the output signal are in the same direction or in opposite directions. A processor is provided for controlling the addition of a reactant to a substance to react with such substance. The product of such reaction along with un-reacted portions of the substance and un-reacted portions of the reactant are directed to a sensor.

Abstract: A method wherein a reactant is added to a substance to react with such substance. The product of such reaction along with un-reacted portions of the substance and un-reacted portions of the reactant are directed to a sensor. The sensor produces an output signal in response to detection of both the un-reacted portions of the substance and the un-reacted portions of the reactant. The method includes changing the amount of reactant added to the substance. A measurement is made to determine whether the change in the amount of reactant and the change the output signal are in the same direction or in opposite directions. A processor is provided for controlling the addition of a reactant to a substance to react with such substance. The product of such reaction along with un-reacted portions of the substance and un-reacted portions of the reactant are directed to a sensor.

Abstract: A method and system for controlling hydrocarbon injection into engine exhaust to reduce NOx. The method and system inject the hydrocarbon into the engine exhaust in accordance with detection of a light-off event. The light-off event can be detected because when there is this hydrocarbon-O2 reaction, such reaction is an exothermic reaction and thus heat is generated and given off. The generation of such heat may be detected by here measuring the difference in temperature across the catalyst. The peak in NOx conversion efficiency temperature changes with age. However, because the peak in NOx conversion efficiency temperature occurs at substantially the same temperature light-off, a determination of light-off by the system and method enables adjustment in the hydrocarbon injection level for maximum NOx reduction efficiency.

Abstract: A method is disclosed for controlling the delivery of compressed air and a reductant for oxides of nitrogen to a mixer from which the air/reductant mixture flows through a nozzle and into an exhaust gas created by a combustion engine. A control signal provided to an air compressor is varied as the exhaust gas pressure changes to maintain a predetermined differential pressure across the nozzle. The desired flow rate of reductant into the exhaust gas is calculated based upon the engine speed, engine load, catalyst temperature, and gas space velocity flowing through the catalyst. A reductant control signal, based upon the calculated reductant flow rate, is provided to a metering pump that delivers the reductant into the mixer. Calculations of the reductant control signal take into account the air pressure that the reductant pump sees inside the mixer.

Abstract: A method for improving NOx conversion efficiency of an exhaust gas after-treatment device is presented. The efficiency is improved by first maintaining the device at an operating temperature wherein improved storage of reductant is possible, and subsequently changing the temperature of the device to that where optimum NOx conversion efficiency is achieved, thereby obtaining and utilizing the conversion benefits of stored reductant.

Abstract: A system 10 is provided for monitoring the loading of a diesel particulate filter 12. System 10 is adapted for use in combination with a vehicle including an internal combustion diesel engine 14 of the type having several substantially identical cylinders 16 which drivably rotate a crankshaft 17. Engine 14 includes an intake manifold 18 which selectively delivers air to cylinders 16, and an exhaust manifold 20 which selectively discharges exhaust gasses from cylinders 16. System 10 includes an engine control unit or controller 40 which is communicatively connected to a pressure sensor 42 that is operatively disposed in the intake manifold 18, and other vehicle operating conditions sensors 44. Controller 40 monitors the signals received from sensors 42 and 44, and based upon the received signals, estimates the loading of the DPF 12 and determines when the DPF 12 should be regenerated.

Abstract: A method of controlling valve landing in a camless engine including a valve movable between fully open and fully closed positions, and an electromagnetic valve actuator for actuating the valve is provided. The method includes providing at least one discrete position measurement sensor to determine when the valve is at a particular position during valve movement. The velocity of the valve is calculated at the particular position based upon current and rate of change of current in the electromagnetic valve actuator when the valve is at the particular position. Valve landing is controlled based upon the calculated velocity.

Abstract: A method of operating one or more valves of a camless internal combustion engine via electronically controlled valve actuators includes the steps of measuring noise related to valve operation, deriving a control signal based at least in part on the measured noise, and applying the valve control signal to one or more of the valve actuators to reduce the effects of noise attributable to valve operation.

Abstract: The present invention provides refrigerant blends which are replacements for chlorodifluoromethane(HCFC-22). The present blends have refrigeration characteristics which are similar to HCFC-22. The blends comprise from about 10 to about 90 weight percent of a first component selected from the group consisting of 1,1,1-trifluoroethane, difluoromethane, propane, and mixtures thereof; from about 1 to about 50 weight percent of a second component selected from the group consisting of hydrofluorocarbon having 1 to 3 carbon atoms, fluorocarbon having 1 to 3 carbon atoms, inorganic compound, and mixtures thereof having a boiling point at atmospheric pressure in the range from about −90 degrees C. to less than −50 degrees C.; and from about 1 to about 50 weight percent of a third component which is hydrofluorocarbon having 1 to 3 carbon atoms, other than 1,1,1-trifluoroethane, having a boiling point at atmospheric pressure in the range from about −50 degrees C. to about −10 degrees C.

Abstract: A method and system for controlling the air charge in a direct injection spark ignition engine that provides proportional plus integral control in positioning an electronic throttle control valve and an exhaust gas recirculating valve in order to compensate for uncertainties in the EGR valve flow area. An adaptation algorithm is used to improve the estimate of in-cylinder flow and throttle open-loop control.

Abstract: An calibration optimization method for a direct injection spark ignition (DISI) engine with a lean NOx trap is disclosed. The method relies on a fixed structure optimization whereby reasonable powertrain operating policies are assumed and parametrized with a small number of variables with some of the variables playing the role of parameters for an inner loop optimization of an outer loop/inner loop two-stage optimization formulation. The values of the parameters are determined via a numerical solution of the resulting (outer loop) optimization to minimize the fuel consumption over the drive cycle subject to emission constraints.

Abstract: A control system 10 and a method 30 for controlling a linearly actuated valve closure member 20 in accordance with the present invention is provided. The method 30 includes a step 32 of determining a control value associated with a control signal indicative of an uncompensated target position of the closure member 20. The method 30 further includes a step 52 of calculating a friction compensation value associated with the closure member 20. The friction compensation value may comprise a static friction compensation value or a coulombic friction compensation value. The method 30 further includes a step 104 of calculating a compensating control value responsive to the control value and the friction compensation value. The method 30 further includes a step 108 of actuating the closure member 20 responsive to the compensating control value.

Abstract: An engine exhaust aftertreatment system is described in which lean NOx, exhaust aftertreatment devices are employed. Because temperature in the exhaust line varies as a function of distance from the engine and engine operating condition, exhaust aftertreatment devices are situated along the exhaust line to ensure that at least one of said exhaust aftertreatment devices operates at a temperature of high NOx conversion efficiency. Reductant quantity is scheduled by the engine's control unit to be supplied to the exhaust aftertreatment devices based on available information provided by sensors or embedded engine control unit models, including: temperature in the exhaust aftertreatment devices, available reductant in the exhaust stream, reductant storage in the exhaust aftertreatment devices, maximum adsorption capacity of the exhaust aftertreatment devices, engine operating conditions, and NOx, concentration.