Abstract: Air purification devices are described. Devices are powered to form an electric field along an airflow path that creates a plasma for destruction of pathogens carried through the device. Devices can be single-user, portable devices for purification of air flow to and/or from a single user.

Abstract: A method for controlling and engine system with a plurality of turbochargers. At least one of the plurality of turbochargers has a turbine valve, a compressor valve, and actuators operable to change the position of the turbine valve. The method comprises controlling the actuator based on the presence of a transient event or a steady state event. During a transient event an engine control module can control the actuators to change the turbine valve to opened and closed positions and the turbine valve to a closed position based on the comparison between a corrected mass flow per turbocharger to a mass flow threshold.

Abstract: A method for controlling and engine system with a plurality of turbochargers. At least one of the plurality of turbochargers has a turbine valve, a compressor valve, and actuators operable to change the position of the turbine valve. The method comprises controlling the actuator based on the presence of a transient event or a steady state event. During a transient event an engine control module can control the actuators to change the turbine valve to opened and closed positions and the turbine valve to a closed position based on the comparison between a corrected mass flow per turbocharger to a mass flow threshold.

Abstract: A method of evaluating operability of a gaseous fuel admission valve of an internal combustion engine is disclosed. The method includes operating the internal combustion engine on gaseous fuel by repeatedly actuating the gaseous fuel admission valve. The method further includes measuring a sequence of temporal developments of an electrical operation parameter respectively associated with an actuation of the gaseous fuel admission valve. The sequence includes a first temporal development to be evaluated and a plurality of temporal developments preceding the first temporal development. The method also includes evaluating operability of the gaseous fuel admission valve based on the first temporal development of the measured sequence and at least one of the plurality of preceding temporal developments of the measured sequence.

Abstract: A method for operating an internal combustion engine includes monitoring engine parameters using an electronic controller, determining a surge speed limit for the engine based on a compressor map, determining an offset engine speed based on a margin between the surge speed limit and an engine speed, determining a minimum engine speed based on the margin, applying the offset engine speed to an engine speed signal to provide an adjusted engine speed, and applying the adjusted engine speed to a desired engine speed when a speed of the engine approaches the surge speed limit.

Abstract: A method for operating an internal combustion engine includes monitoring engine parameters using an electronic controller, determining a surge speed limit for the engine based on a compressor map, determining an offset engine speed based on a margin between the surge speed limit and an engine speed, determining a minimum engine speed based on the margin, applying the offset engine speed to an engine speed signal to provide an adjusted engine speed, and applying the adjusted engine speed to a desired engine speed when a speed of the engine approaches the surge speed limit.

Abstract: A method of evaluating operability of a gaseous fuel admission valve of an internal combustion engine is disclosed. The method includes operating the internal combustion engine on gaseous fuel by repeatedly actuating the gaseous fuel admission valve. The method further includes measuring a sequence of temporal developments of an electrical operation parameter respectively associated with an actuation of the gaseous fuel admission valve. The sequence includes a first temporal development to be evaluated and a plurality of temporal developments preceding the first temporal development. The method also includes evaluating operability of the gaseous fuel admission valve based on the first temporal development of the measured sequence and at least one of the plurality of preceding temporal developments of the measured sequence.

Abstract: A system and method for measuring an EGR flow rate for an engine having an EGR valve with a selectable EGR valve position and a venturi sensor situated to take a differential pressure measurement relative to recirculated exhaust gas includes determining an EGR valve effective area based on the EGR valve position, determining a weighting factor based on the effective area, calculating a first EGR flow estimate based on the effective area, and calculating a second EGR flow estimate based on the differential pressure measurement of the venturi sensor. A final EGR flow rate is determined based on the weighting factor, the first EGR flow estimate, and the second EGR flow estimate.

Abstract: Controlling a gaseous fuel internal combustion engine includes receiving a signal indicative of a desired state of an operating parameter of the engine dependent upon a fueling rate, and tracking the desired state via adjusting a pressure drop from a gaseous fuel common rail to an intake conduit such that the fueling rate is adjusted toward a fueling accordant with the desired state. The control further includes limiting an error in the tracking via executing the adjustment of the pressure drop responsive to a fluid pressure disturbance within the intake conduit.

Abstract: A system and method for measuring an EGR flow rate for an engine having an EGR valve with a selectable EGR valve position and a venturi sensor situated to take a differential pressure measurement relative to recirculated exhaust gas includes determining an EGR valve effective area based on the EGR valve position, determining a weighting factor based on the effective area, calculating a first EGR flow estimate based on the effective area, and calculating a second EGR flow estimate based on the differential pressure measurement of the venturi sensor. A final EGR flow rate is determined based on the weighting factor, the first EGR flow estimate, and the second EGR flow estimate.

Abstract: An internal combustion engine includes an exhaust restriction valve and an exhaust gas recirculation control valve. Upon determining that a malfunction or fault condition exists relative to one of the valves, the controller may command the other valve to move towards a predetermined position. A malfunction or fault condition may result in derating of the engine.

Abstract: An internal combustion engine and control system are provided having improved efficiency through improved exhaust flow control. The engine includes at least one bank of combustion cylinders and a respective exhaust manifold for conveying exhaust to the atmosphere. Further included is an exhaust gas restriction valve (ERV) associated with the exhaust manifold for selectively increasing backpressure on the associated bank of combustion cylinders and for redirecting a portion of the exhaust into an exhaust gas conditioning system for conditioning the portion of the exhaust and returning it to an air intake of the engine. An engine exhaust gas recirculation (EGR) valve in the exhaust gas recirculation system restricts the flow of conditioned exhaust, and an EGR flow controller operates the EGR valve in one of a substantially open and substantially closed condition and controls the flow of conditioned exhaust to the air intake by modulating the ERV.

Abstract: A pump for a fuel system is disclosed. The pump has a housing defining at least one pumping chamber, and a plunger. The plunger is movable to draw a fluid into and displace the fluid from the at least one pumping chamber. The pump also has a metering valve and a controller. The metering valve has a valve element movable to selectively meter fluid drawn into the at least one pumping chamber. The controller is configured to receive an indication of a desired discharge characteristic and reference a first map to determine an inlet opening area corresponding to the desired discharge characteristic. The controller is also configured to reference a second map to determine a position of the metering valve corresponding to the determined inlet opening area, and to send a control signal to the metering valve indicative of the determined position.

Abstract: A method of initially operating an internal combustion engine including operating the engine in a start-up mode is provided. The start-up mode includes injecting at least two fuel pre-shots wherein a first of the fuel pre-shots is smaller in quantity than a last of the fuel pre-shots. An engine is provided including an electronic controller with a computer readable medium having a control algorithm recorded thereon, the control algorithm including means for commanding injection of a main fuel shot and at least two fuel pre-shots wherein a first of the fuel pre-shots is smaller in quantity than a last of the fuel pre-shots.

Abstract: A fuel injector for an internal combustion engine is disclosed. The fuel injector has a plunger, an electronically controlled check valve, and a controller in communication with the electronically controlled check valve. The controller is configured to receive a indication of a desired start of injection timing relative to an angular position of a crankshaft of the engine, and a desired injection quantity. The controller is also configured to determine a displacement of the plunger based on an angular position of the crankshaft; to determine a start of current for the electronically controlled check valve relative to plunger displacement that results in the desired start of injection timing, and to determine an end of current for the electronically controlled check valve relative to plunger displacement that results in the desired injection quantity. The controller is further configured to affect the determined start and end of current for the electronically controlled check valve.

Abstract: The minimum desired engine speed for engaging engine braking varies. The disclosed method includes determining a speed error by subtracting the desired engine speed from the actual engine speed, comparing the speed error to an error threshold, and generating a brake enable command if the speed error is greater than or equal to the error threshold.

Abstract: A method and apparatus for trimming a fuel injector located on an engine. The method and apparatus includes modifying an engine speed control, interrupting at least one injection event, monitoring a change associated with an engine speed, and responsively trimming the injector.

Abstract: A method and apparatus for trimming a fuel injector located on an engine. The method and apparatus includes modifying an engine speed control, interrupting at least one injection event, monitoring a change associated with an engine speed, and responsively trimming the injector.