Abstract: Systems, methods and techniques for exhaust gas recirculation are provided. The system includes controlling the mixing of exhaust flow from at least one cylinder of an engine with air in an air intake system prior to combustion in response to an EGR fraction deviation condition. The exhaust flow from the at least one cylinder is accumulated prior to mixing and distributed into the intake air system in a controlled manner to mitigate or prevent the EGR flow from deviating from an expected EGR fraction.

Abstract: A waste heat recovery (WHR) system operates in a reverse mode, permitting using the WHR system to transfer heat to the exhaust gas of an internal combustion engine. In another configuration, a WHR system may operate in two modes. The first mode removes heat from exhaust gas of an engine to perform useful work. The second mode transfers heat to the exhaust gas. The benefit of this flexible system is that a WHR system is adaptable to rapidly heat exhaust gas at startup and during other conditions where the temperature of the exhaust gas is less than a predetermined operating range. Because of the ability to rapidly warm engine exhaust gas, an exhaust gas receiving system, such as an EGR or an aftertreatment system, may function to reduce the emissions of the engine more quickly. Because this system is reversible, it retains the capability of a conventional WHR system.

Abstract: Systems and methods for internal combustion engine operation with exhaust gas recirculation and turbocharging are disclosed. The systems include an exhaust gas recirculation loop for recirculating exhaust gas flow from a first portion of the cylinders of the engine into an intake system prior to combustion. The system further includes a turbine with first and second inlets for receiving exhaust gas flows from respective first and second parts of the exhaust gas of the remaining portion of the cylinders.

Abstract: A waste heat recovery (WHR) system operates in a reverse mode, permitting using the WHR system to transfer heat to the exhaust gas of an internal combustion engine. In another configuration, a WHR system may operate in two modes. The first mode removes heat from exhaust gas of an engine to perform useful work. The second mode transfers heat to the exhaust gas. The benefit of this flexible system is that a WHR system is adaptable to rapidly heat exhaust gas at startup and during other conditions where the temperature of the exhaust gas is less than a predetermined operating range. Because of the ability to rapidly warm engine exhaust gas, an exhaust gas receiving system, such as an EGR or an aftertreatment system, may function to reduce the emissions of the engine more quickly. Because this system is reversible, it retains the capability of a conventional WHR system.

Abstract: Systems and methods for fuelling a plurality of cylinders of an internal combustion engine are disclosed. The system includes a dedicated exhaust gas recirculation system for recirculating exhaust gas flow from at least one dedicated cylinder of an engine into an intake system prior to combustion. The system further includes a fueling system to provide a first flow of fuel to each of the plurality of cylinders and a second flow of fuel to each of the dedicated cylinders that is in addition to the first flow of fuel.

Abstract: A system includes an internal combustion ignition engine with an exhaust gas flow, a particulate filter in the exhaust gas flow, a NOx reduction catalyst in the exhaust gas flow downstream of the particulate filter, a first oxygen sensor coupled to the exhaust gas flow downstream of the NOx reduction catalyst, and a second oxygen sensor coupled to the exhaust gas flow between the particulate filter and the NOx reduction catalyst. A controller includes an exhaust conditions module that interprets a first oxygen signal from the first oxygen sensor and a second oxygen signal from the second oxygen sensor and a combustion control module that commands a high engine-out air-fuel ratio when the first oxygen signal indicates a low oxygen content and commands a low engine-out air-fuel ratio when the first oxygen signal indicates a high oxygen content.

Abstract: Systems and methods for exhaust gas recirculation are provided. The system includes a dedicated exhaust gas recirculation loop for recirculating exhaust gas flow from at least one dedicated cylinder of an engine into an intake system prior to combustion. The system further includes a low pressure exhaust gas recirculation loop for increasing the exhaust gas recirculation amount above that provided by the dedicated exhaust gas recirculation loop.

Abstract: A system includes an internal combustion ignition engine with an exhaust gas flow, a particulate filter in the exhaust gas flow, a NOx reduction catalyst in the exhaust gas flow downstream of the particulate filter, a first oxygen sensor coupled to the exhaust gas flow downstream of the NOx reduction catalyst, and a second oxygen sensor coupled to the exhaust gas flow between the particulate filter and the NOx reduction catalyst. A controller includes an exhaust conditions module that interprets a first oxygen signal from the first oxygen sensor and a second oxygen signal from the second oxygen sensor and a combustion control module that commands a high engine-out air-fuel ratio when the first oxygen signal indicates a low oxygen content and commands a low engine-out air-fuel ratio when the first oxygen signal indicates a high oxygen content.

Abstract: Systems, methods and techniques for exhaust gas recirculation are provided. The system includes mixing exhaust flow from at least one cylinder of an engine with air in an air intake system prior to combustion. The exhaust flow from the at least one cylinder is accumulated prior to mixing and distributed into the intake air system in a controlled manner.

Abstract: A waste heat recovery (WHR) system operates in a reverse mode, permitting using the WHR system to transfer heat to the exhaust gas of an internal combustion engine. In another configuration, a WHR system may operate in two modes. The first mode removes heat from exhaust gas of an engine to perform useful work. The second mode transfers heat to the exhaust gas. The benefit of this flexible system is that a WHR system is adaptable to rapidly heat exhaust gas at startup and during other conditions where the temperature of the exhaust gas is less than a predetermined operating range. Because of the ability to rapidly warm engine exhaust gas, an exhaust gas receiving system, such as an EGR or an aftertreatment system, may function to reduce the emissions of the engine more quickly. Because this system is reversible, it retains the capability of a conventional WHR system.

Abstract: An engine system including a lean burn active ignition engine and aftertreatment system, and a method for operating such a system, are disclosed. In a representative embodiment, the lean burn active ignition engine includes an engine block including plural cylinders, an intake manifold adapted to provide charge air to the cylinders, an exhaust manifold, an active ignition source; and fuel and air handling systems that provide fuel/charge air mixture such that an air-to-fuel ratio of the mixed charge air and fuel in each of the engine cylinders is substantially greater than a stoichiometric quantity to achieve a lean burn condition. An exhaust gas aftertreatment system is fluidly coupled to an outlet of the exhaust manifold and includes an oxidation-reduction catalyst, and a selective catalytic reduction (SCR) catalyst fluidly coupled to the oxidation-reduction catalyst and positioned downstream of the oxidation-reduction catalyst.

Abstract: A system includes an internal combustion ignition engine with an exhaust gas flow, a particulate filter in the exhaust gas flow, a NOx reduction catalyst in the exhaust gas flow downstream of the particulate filter, a first oxygen sensor coupled to the exhaust gas flow downstream of the NOx reduction catalyst, and a second oxygen sensor coupled to the exhaust gas flow between the particulate filter and the NOx reduction catalyst. A controller includes an exhaust conditions module that interprets a first oxygen signal from the first oxygen sensor and a second oxygen signal from the second oxygen sensor and a combustion control module that commands a high engine-out air-fuel ratio when the first oxygen signal indicates a low oxygen content and commands a low engine-out air-fuel ratio when the first oxygen signal indicates a high oxygen content.