Abstract: An engine system includes an engine having first and second exhaust manifolds each having outlet ports and a bypass runner. A first turbocharger is in fluid communication with the outlet port of the first manifold, and a second turbocharger in fluid communication with the outlet port of the second manifold. An exhaust aftertreatment device is in fluid communication with the first and second turbochargers. A turbocharger bypass circuit includes a valve assembly having an inlet side connected in fluid communication with the bypass runners of the first and second manifolds, an outlet side in fluid communication with the aftertreatment device, and a valve having an open position in which the inlet and outlet sides are in fluid communication and a closed position in which the inlet and outlet sides are not in fluid communication.

Abstract: An engine system includes an engine having first and second exhaust manifolds each having outlet ports and a bypass runner. A first turbocharger is in fluid communication with the outlet port of the first manifold, and a second turbocharger in fluid communication with the outlet port of the second manifold. An exhaust aftertreatment device is in fluid communication with the first and second turbochargers. A turbocharger bypass circuit includes a valve assembly having an inlet side connected in fluid communication with the bypass runners of the first and second manifolds, an outlet side in fluid communication with the aftertreatment device, and a valve having an open position in which the inlet and outlet sides are in fluid communication and a closed position in which the inlet and outlet sides are not in fluid communication.

Abstract: Methods and systems are provided for a turbocharger system to reduce and balance axial thrust load on the turbine shaft and the associated bearing system and sealing. In one example, a partial back plate compressor may be used in combination with an axial turbine to reduce axial thrust load and to improve turbocharger transient response time. In another example, a regenerative turbocharger system with back-to-back turbo pump may be used to reduce and balance axial thrust load.

Abstract: Methods and systems are provided for controlling boost pressure and exhaust gas recirculation in a split exhaust system. In one example, a first portion of exhaust may be routed from a cylinder to an exhaust turbine via a first exhaust valve and a second, remaining portion of exhaust may be routed as exhaust gas recirculation (EGR) via a second exhaust valve, the timing and lift of each of the first valve profile and the second valve profile adjusted based on boost error and EGR error. Further, motor torque from an electric motor may be supplied to the turbocharger to attain a desired boost pressure and a desired EGR flow.

Abstract: Various systems and methods are described for a variable geometry turbine. In one example, a nozzle vane includes a stationary having a first cambered sliding surface and a sliding vane having a second cambered sliding surface where the second cambered sliding surface includes a flow disrupting feature in contact with the first sliding cambered surface. The sliding vane may be positioned to slide in a direction from substantially tangent along a curved path to an inner circumference of the turbine nozzle and selectively uncover the flow disrupting feature.

Abstract: A turbocharger compressor and method are provided including a first coolant passage in thermal contact with an inlet configured to direct the charge gas toward an impeller; and second, third, and fourth coolant passages respectively in thermal contact with impeller, volute, and diffuser regions. All of the coolant passages are fluidically coupled with a heat exchanger. One or more of the coolant passages are configured such that coolant flows in an upstream direction relative to a general flow direction of charge gas through the compressor.

Abstract: Methods and systems are provided for a turbocharger system to reduce and balance axial thrust load on the turbine shaft and the associated bearing system and sealing. In one example, a partial back plate compressor may be used in combination with an axial turbine to reduce axial thrust load and to improve turbocharger transient response time. In another example, a regenerative turbocharger system with back-to-back turbo pump may be used to reduce and balance axial thrust load.

Abstract: Methods and systems are provided for a turbocharger system to reduce and balance axial thrust load on the turbine shaft and the associated bearing system and sealing. In one example, a partial back plate compressor may be used in combination with an axial turbine to reduce axial thrust load and to improve turbocharger transient response time. In another example, a regenerative turbocharger system with back-to-back turbo pump may be used to reduce and balance axial thrust load.

Abstract: A turbocharger compressor and method are provided including a first coolant passage in thermal contact with an inlet configured to direct the charge gas toward an impeller; and second, third, and fourth coolant passages respectively in thermal contact with impeller, volute, and diffuser regions. All of the coolant passages are fluidically coupled with a heat exchanger. One or more of the coolant passages are configured such that coolant flows in an upstream direction relative to a general flow direction of charge gas through the compressor.

Abstract: Methods and systems are provided for controlling boost pressure and exhaust gas recirculation in a split exhaust system. In one example, a first portion of exhaust may be routed from a cylinder to an exhaust turbine via a first exhaust valve and a second, remaining portion of exhaust may be routed as exhaust gas recirculation (EGR) via a second exhaust valve, the timing and lift of each of the first valve profile and the second valve profile adjusted based on boost error and EGR error. Further, motor torque from an electric motor may be supplied to the turbocharger to attain a desired boost pressure and a desired EGR flow.

Abstract: Methods and systems are provided for controlling boost pressure and exhaust gas recirculation in a split exhaust system. In one example, a first portion of exhaust may be routed from a cylinder to an exhaust turbine via a first exhaust valve and a second, remaining portion of exhaust may be routed as exhaust gas recirculation (EGR) via a second exhaust valve, the timing and lift of each of the first valve profile and the second valve profile adjusted based on boost error and EGR error. Further, motor torque from an electric motor may be supplied to the turbocharger to attain a desired boost pressure and a desired EGR flow.

Abstract: Various systems and methods are described for a variable geometry turbine. In one example, a nozzle vane includes a stationary having a first cambered sliding surface and a sliding vane having a second cambered sliding surface where the second cambered sliding surface includes a flow disrupting feature in contact with the first sliding cambered surface. The sliding vane may be positioned to slide in a direction from substantially tangent along a curved path to an inner circumference of the turbine nozzle and selectively uncover the flow disrupting feature.

Abstract: Various systems and methods are described for a variable geometry turbine. In one example, a nozzle vane includes a stationary having a first cambered sliding surface and a sliding vane having a second cambered sliding surface where the second cambered sliding surface includes a flow disrupting feature in contact with the first sliding cambered surface. The sliding vane may be positioned to slide in a direction from substantially tangent along a curved path to an inner circumference of the turbine nozzle and selectively uncover the flow disrupting feature.

Abstract: Methods and systems are provided for reducing vacuum at an outlet of an upstream first compressor when powering on a second compressor positioned downstream of the first compressor. In one example, a method may comprise, in response to a desired engine torque increasing above a threshold: powering on a second compressor positioned downstream of a first compressor in an intake of an engine system, and opening a compressor recirculation valve (CRV) positioned in a bypass passage coupled across the first compressor for a duration. As such, a portion of intake gasses from upstream of the first compressor may be routed to the second compressor.

Abstract: Methods and systems are provided for adjusting a phase of gaseous fuel delivered to fuel injectors of a fuel delivery system. In one example, a method may include adjusting a fuel pressure in a fuel delivery system to deliver fuel in each of a liquid and a gaseous phase during different engine operating conditions. The fuel pressure may be based on a temperature, composition, and desired phase of the fuel.

Abstract: Methods and systems are provided for reducing vacuum at an outlet of an upstream first compressor when powering on a second compressor positioned downstream of the first compressor. In one example, a method may comprise, in response to a desired engine torque increasing above a threshold: powering on a second compressor positioned downstream of a first compressor in an intake of an engine system, and opening a compressor recirculation valve (CRV) positioned in a bypass passage coupled across the first compressor for a duration. As such, a portion of intake gasses from upstream of the first compressor may be routed to the second compressor.

Abstract: Methods and systems are provided for a turbocharger system to reduce and balance axial thrust load on the turbine shaft and the associated bearing system and sealing. In one example, a partial back plate compressor may be used in combination with an axial turbine to reduce axial thrust load and to improve turbocharger transient response time. In another example, a regenerative turbocharger system with back-to-back turbo pump may be used to reduce and balance axial thrust load.

Abstract: A method for operating an engine is disclosed. In one example, internal EGR is increased during conditions where cooled EGR is at a higher concentration during a decreasing engine load so that homogeneous compression ignition may be initiated at lower engine loads.

Abstract: A method for an engine, comprising: during a first condition comprising a high engine temperature, injecting a first quantity of liquid petroleum gas into a first engine cylinder at a first timing during an intake stroke; and injecting a second quantity of liquid petroleum gas into the first engine cylinder at a second timing during a compression stroke following the intake stroke. In this way, combustion knock and cylinder pre-ignition may be mitigated without retarding spark ignition and/or limiting engine load, thereby allowing for maximum engine performance.

Abstract: Methods and systems are provided for delivering gaseous fuel as multiple fuel injections split between an intake stroke, a compression stroke, and/or a power stroke to expedite exhaust catalyst heating during an engine cold-start. Fuel injected in the intake and compression stroke is ignited and combusted. The power stroke fuel injections are combusted in the exhaust port to increase exhaust temperature and pressure for faster catalyst light-off.