The exhaust gas recirculation system includes a plurality of coolers arranged in a predefined configuration that are configured to receive a flow of exhaust gas and a flow of coolant therethrough. The exhaust gas recirculation system further includes plurality of valves associated with each of the plurality of coolers. The plurality of valves is configured to regulate at least one of the flows of exhaust gas and the coolant through the corresponding cooler. The exhaust gas recirculation system also includes a control unit configured to selectively switch opening and closing of the plurality of valves such that at least one of the flow of exhaust gas and the flow of coolant through at least one cooler of the plurality of coolers is regulated during an operation of the exhaust gas recirculation system, to actively regenerate the at least one cooler.

An exhaust gas recirculation system for an engine includes a conduit, and a mixer. The conduit is configured to direct to direct exhaust gas away from an exhaust manifold. The mixer is configured to direct exhaust gas from the conduit, into an engine air intake system. The mixer is arranged with an exhaust gas mixing volute chamber having a plurality of mixing vanes configured to direct the exhaust gas into a central intake airflow upstream of an intake manifold.

Active control of one or more exhaust gas recirculation loops is provided to manage and EGR fraction in the charge flow to produce desired operating conditions and/or provide diagnostics in response to at least one of an oxygen concentration and a NOx concentration in the charge flow and in the exhaust flow.

Active control of one or more exhaust gas recirculation loops is provided to manage and EGR fraction in the charge flow to produce desired operating conditions and/or provide diagnostics in response to at least one of an oxygen concentration and a NOx concentration in the charge flow and in the exhaust flow.

Systems, methods and apparatus for controlling operation of an engine structured to combust gaseous fuel such as a dual fuel engine, including an estimation of key parameters dependent on natural gas quality, are disclosed. The natural gas quality parameters are estimated from natural gas properties obtained from various sensed parameters associated with the engine.

Various systems and methods are provided for exhaust gas recirculation. In one example, an exhaust gas recirculation (EGR) system includes an EGR passage coupling an engine exhaust system to an engine intake system, a first EGR cooler positioned in the EGR passage, the first EGR cooler configured to cool EGR with a first fluid, and a second EGR cooler positioned in the EGR passage downstream of the first EGR cooler, the second EGR cooler configured to cool EGR with a second fluid.

Various systems and methods are provided for exhaust gas recirculation. In one example, an exhaust gas recirculation (EGR) system includes an EGR passage coupling an engine exhaust system to an engine intake system, a first EGR cooler positioned in the EGR passage, the first EGR cooler configured to cool EGR with a first fluid, and a second EGR cooler positioned in the EGR passage downstream of the first EGR cooler, the second EGR cooler configured to cool EGR with a second fluid.

An arrangement for converting thermal energy from lost heat of an internal combustion engine into mechanical energy includes a working circuit for a working medium. An expansion engine is disposed in the working circuit. A heat exchanger is mounted upstream of the expansion engine in a flow direction of the working medium where the working circuit extends through the heat exchange. The heat exchanger includes an exhaust gas recirculation heat exchanger having a cold part and a warm part, an exhaust gas heat exchanger, and a phase transition cooling in the internal combustion engine. The heat exchanger is formed by serial connection in a sequence of the cold part of the exhaust gas recirculation heat exchanger, the exhaust gas heat exchanger, the phase transition cooling in the internal combustion engine, and the warm part of the exhaust gas recirculation heat exchanger.

Methods and systems are provided for directing the flow of recirculated exhaust gas (EGR) delivered to an EGR cooler. In one example, a method includes flowing EGR through an EGR cooler positioned in an EGR passage, the EGR cooler comprising a bypass passage, a first cooler core flow path, and a second cooler core flow path, and adjusting a valve of the EGR cooler to selectively block flow of the EGR through the bypass passage, the first cooler core flow path, and the second cooler core flow path. In this way, fouling of the EGR cooler may be reduced.

Methods and systems are provided for directing the flow of recirculated exhaust gas (EGR) delivered to an EGR cooler. In one example, a method includes flowing EGR through an EGR cooler positioned in an EGR passage, the EGR cooler comprising a bypass passage, a first cooler core flow path, and a second cooler core flow path, and adjusting a valve of the EGR cooler to selectively block flow of the EGR through the bypass passage, the first cooler core flow path, and the second cooler core flow path. In this way, fouling of the EGR cooler may be reduced.