Abstract: This disclosure provides a system and method that eliminates the need for manually calibrating or adjusting a dual fuel internal combustion engine to compensate for variations in composition of a gaseous fuel or other variations, such as ambient or site conditions. The system and method functions by determining an engine load, determining an advantageous gaseous fuel substitution rate from the engine load and speed in addition to an actual gaseous fuel substitution rate, modifying the advantageous gaseous fuel substitution rate by a minimum liquid fuel flow rate, engine protection parameters, and oxidation catalyst protection parameters, and then determining an error term in response to the modified advantageous gaseous fuel substitution rate and the actual gaseous fuel substitution rate. The error term is used to adjust a gaseous fuel control valve.

Abstract: An exhaust aftertreatment system for treating exhaust flow from an internal combustion engine, and associated method, allows for independent control of exhaust flow through plural exhaust legs of the exhaust aftertreatment system. The independent control of exhaust flow is carried out by adjusting a valve positioned in each the exhaust legs based on a value of a signal generated by a flow measurement device positioned along at least one of the exhaust legs. The valves can be adjusted to force a target flow in a exhaust leg, relative flow among exhaust legs, exhaust temperature in an exhaust leg, exhaust backpressure and/or imbalance within the exhaust legs.

Abstract: A premixed charge compression ignition engine, and a control system, is provided which effectively initiates combustion by compression ignition and maintains stable combustion while achieving extremely low nitrous oxide emissions, good overall efficiency and acceptable combustion noise and cylinder pressures. The present engine and control system effectively controls the combustion history, that is, the time at which combustion occurs, the rate of combustion, the duration of combustion and/or the completeness of combustion, by controlling the operation of certain control variables providing temperature control, pressure control, control of the mixture's autoignition properties and equivalence ratio control. The combustion control system provides active feedback control of the combustion event and includes a sensor, e.g. pressure sensor, for detecting an engine operating condition indicative of the combustion history, e.g. the start of combustion, and generating an associated engine operating condition signal.

Abstract: A multi-mode internal combustion engine and method of operating the engine is provided which is capable of operating in a variety of modes based on engine operating conditions to enhance fuel efficiency and reduce emissions. The multi-mode engine include a fuel delivery system and control system for permitting the engine to operate in a diesel mode, a homogeneous charge dual fuel transition mode, a spark ignition or liquid spark ignition mode and/or a premixed charge compression ignition mode. The control system and method permits the engine operation to transfer between the various modes in an effective and efficient manner by controlling one or more fuel delivery devices or other engine components so as to move along a continuous transfer path while maintaining engine torque at a substantially constant level.

Abstract: A multi-mode internal combustion engine and method of operating the engine is provided which is capable of operating in a variety of modes based on engine operating conditions to enhance fuel efficiency and reduce emissions. The multi-mode engine include a fuel delivery system and control system for permitting the engine to operate in a diesel mode, a homogeneous charge dual fuel transition mode, a spark ignition or liquid spark ignition mode and/or a premixed charge compression ignition mode. The control system and method permits the engine operation to transfer between the various modes in an effective and efficient manner by controlling one or more fuel delivery devices or other engine components so as to move along a continuous transfer path while maintaining engine torque at a substantially constant level.

Abstract: A premixed charge compression ignition engine, and a control system, is provided which effectively initiates combustion by compression ignition and maintains stable combustion while achieving extremely low nitrous oxide emissions, good overall efficiency and acceptable combustion noise and cylinder pressures. The present engine and control system effectively controls the combustion history, that is, the time at which combustion occurs, the rate of combustion, the duration of combustion and/or the completeness of combustion, by controlling the operation of certain control variables providing temperature control, pressure control, control of the mixture's autoignition properties and equivalence ratio control. The combustion control system provides active feedback control of the combustion event and includes a sensor, e.g. pressure sensor, for detecting an engine operating condition indicative of the combustion history, e.g. the start of combustion, and generating an associated engine operating condition signal.

Abstract: A multi-mode internal combustion engine and method of operating the engine is provided which is capable of operating in a variety of modes based on engine operating conditions to enhance fuel efficiency and reduce emissions. The multi-mode engine include a fuel delivery system and control system for permitting the engine to operate in a diesel mode, a homogeneous charge dual fuel transition mode, a spark ignition or liquid spark ignition mode and/or a premixed charge compression ignition mode. The control system and method permits the engine operation to transfer between the various modes in an effective and efficient manner by controlling one or more fuel delivery devices or other engine components so as to move along a continuous transfer path while maintaining engine torque at a substantially constant level.

Abstract: A method and internal combustion engine operable in a premixed charge compression ignition mode, comprising a combustion chamber, an intake system for delivering intake air, a mixing device that mixes a first fuel with the intake air to provide a premixed charge of air and the first fuel, a direct fuel injector adapted to directly inject a second fuel into the combustion chamber, and a control system adapted to control the direct fuel injector in a manner to provide a post-ignition injection where the second fuel is directly injected into the combustion chamber after onset of ignition of the premixed charge in the combustion chamber. The second fuel is preferably injected into the combustion chamber during combustion of the premixed charge and/or shortly after combustion of the premixed charge in the combustion chamber.

Abstract: An internal combustion engine operable in a premixed charge compression ignition mode and a method for operating the engine, the engine including an engine body with a piston assembly, a combustion chamber formed in the engine body by the piston assembly, an intake system for delivering intake air to the combustion chamber during an intake stroke, a mixing device that mixes a first fuel with the intake air to provide a premixed charge of air and the first fuel, a direct fuel injector adapted to directly inject a second fuel into the combustion chamber, and a control system adapted to control the direct fuel injector in a manner to provide at least one early control injection, and preferably, a plurality of early control injections of the second fuel into the combustion chamber before start of combustion of the premixed charge.

Abstract: A premixed charge compression ignition engine, and a control system, is provided which effectively initiates combustion by compression ignition and maintains stable combustion while achieving extremely low nitrous oxide emissions, good overall efficiency and acceptable combustion noise and cylinder pressures. The present engine and control system effectively controls the combustion history, that is, the time at which combustion occurs, the rate of combustion, the duration of combustion and/or the completeness of combustion, by controlling the operation of certain control variables providing temperature control, pressure control, control of the mixture's autoignition properties and equivalence ratio control. The combustion control system provides active feedback control of the combustion event and includes a sensor, e.g. pressure sensor, for detecting an engine operating condition indicative of the combustion history, e.g. the start of combustion, and generating an associated engine operating condition signal.

Abstract: A multi-mode internal combustion engine and method of operating the engine is provided which is capable of operating in a variety of modes based on engine operating conditions to enhance fuel efficiency and reduce emissions. The multi-mode engine include a fuel delivery system and control system for permitting the engine to operate in a diesel mode, a homogeneous charge dual fuel transition mode, a spark ignition or liquid spark ignition mode and/or a premixed charge compression ignition mode. The control system and method permits the engine operation to transfer between the various modes in an effective and efficient manner by controlling one or more fuel delivery devices or other engine components so as to move along a continuous transfer path while maintaining engine torque at a substantially constant level.

Abstract: An apparatus and methods for effectively determining the start of combustion in a cylinder of an internal combustion engine where the start of combustion is calculated by obtaining cylinder pressure data (P), processing the cylinder pressure data (P) into a processed pressure value indicative of the occurrence of SOC, comparing the processed pressure value to a predetermined threshold value, if the processed pressure value crosses the predetermined threshold value, determining that SOC has occurred, and calculating a crank shaft location at which the predetermined threshold value was crossed by the processed pressure value thereby identifying the crank shaft location at which SOC occurred. In alternative embodiments, optional steps may be provided including a verification step, a windowing step, a filtering step, determining occurrence of misfire, and determining occurrence of retarded timing.

Abstract: A multi-mode internal combustion engine and method of operating the engine is provided which is capable of operating in a variety of modes based on engine operating conditions to enhance fuel efficiency and reduce emissions. The multi-mode engine include a fuel delivery system and control system for permitting the engine to operate in a diesel mode, a homogeneous charge dual fuel transition mode, a spark ignition or liquid spark ignition mode and/or a premixed charge compression ignition mode. The control system and method permits the engine operation to transfer between the various modes in an effective and efficient manner by controlling one or more fuel delivery devices or other engine components so as to move along a continuous transfer path while maintaining engine torque at a substantially constant level.

Abstract: A novel and improved engine and method are provided which includes a premixed charge compression ignition engine capable of operating over a wide load range without the need to vary the IMT beyond easily achievable or desirable temperature levels. The engine and method adjust the start of combustion by adjusting the engine speed and torque while delivering a targeted engine horsepower output.

Abstract: An apparatus and methods for effectively determining the start of combustion in a cylinder of an internal combustion engine where the start of combustion is calculated by obtaining cylinder pressure data (P), processing the cylinder pressure data (P) into a processed pressure value indicative of the occurrence of SOC, comparing the processed pressure value to a predetermined threshold value, if the processed pressure value crosses the predetermined threshold value, determining that SOC has occurred, and calculating a crank shaft location at which the predetermined threshold value was crossed by the processed pressure value thereby identifying the crank shaft location at which SOC occurred. In alternative embodiments, optional steps may be provided including a verification step, a windowing step, a filtering step, determining occurrence of misfire, and determining occurrence of retarded timing.

Abstract: A premixed charge compression ignition engine, and a control system, is provided which effectively initiates combustion by compression ignition and maintains stable combustion while achieving extremely low nitrous oxide emissions, good overall efficiency and acceptable combustion noise and cylinder pressures. The present engine and control system effectively controls the combustion history, that is, the time at which combustion occurs, the rate of combustion, the duration of combustion and/or the completeness of combustion, by controlling the operation of certain control variables providing temperature control, pressure control, control of the mixture's autoignition properties and equivalence ratio control. The combustion control system provides active feedback control of the combustion event and includes a sensor, e.g. pressure sensor, for detecting an engine operating condition indicative of the combustion history, e.g. the start of combustion, and generating an associated engine operating condition signal.

Abstract: An electric power generation system is disclosed, which includes a back-up electric power generator driven by a four-cycle internal combustion engine. The engine includes a plurality of reciprocating cylinders each rotatably coupled to a crankshaft, which drives the electric power generator. The engine also includes a compressor along an intake pathway to deliver pressurized air to the cylinders and a turbine along an exhaust pathway to power the compressor when driven by exhaust discharged from the cylinders. The engine is prepared to accept a generator load by increasing boost pressure provided by the compressor. This increase is accomplished by skip-firing the cylinders in a selected pattern, retarding ignition timing for the cylinders, or a combination of these techniques. A unique skip-fueling control pattern is also disclosed.

Abstract: An internal combustion engine operable in a premixed charge compression ignition mode and a method for operating the engine, the engine including an engine body with a piston assembly, a combustion chamber formed in the engine body by the piston assembly, an intake system for delivering intake air to the combustion chamber during an intake stroke, a mixing device that mixes a first fuel with the intake air to provide a premixed charge of air and the first fuel, a direct fuel injector adapted to directly inject a second fuel into the combustion chamber, and a control system adapted to control the direct fuel injector in a manner to provide at least one early control injection, and preferably, a plurality of early control injections of the second fuel into the combustion chamber before start of combustion of the premixed charge.

Abstract: A premixed charge compression ignition engine, and a control system, is provided which effectively initiates combustion by compression ignition and maintains stable combustion while achieving extremely low nitrous oxide emissions, good overall efficiency and acceptable combustion noise and cylinder pressures. The present engine and control system effectively controls the combustion history, that is, the time at which combustion occurs, the rate of combustion, the duration of combustion and/or the completeness of combustion, by controlling the operation of certain control variables providing temperature control, pressure control, control of the mixture's autoignition properties and equivalence ratio control. The combustion control system provides active feedback control of the combustion event and includes a sensor, e.g. pressure sensor, for detecting an engine operating condition indicative of the combustion history, e.g. the start of combustion, and generating an associated engine operating condition signal.

Abstract: A method and internal combustion engine operable in a premixed charge compression ignition mode, comprising a combustion chamber, an intake system for delivering intake air, a mixing device that mixes a first fuel with the intake air to provide a premixed charge of air and the first fuel, a direct fuel injector adapted to directly inject a second fuel into the combustion chamber, and a control system adapted to control the direct fuel injector in a manner to provide a post-ignition injection where the second fuel is directly injected into the combustion chamber after onset of ignition of the premixed charge in the combustion chamber. The second fuel is preferably injected into the combustion chamber during combustion of the premixed charge and/or shortly after combustion of the premixed charge in the combustion chamber.