An EGR device includes a housing and an inner pipe. The housing has an outer pipe. The inner pipe is accommodated in the outer pipe. The inner pipe defines an inner passage internally and defines an annular passage externally with the outer pipe. The inner pipe has through holes communicating the inner passage with the annular passage. At least one diffuser is equipped to the through holes. The diffuser is projected radially inward.

An intake system may include a purge supply device; an exhaust gas recirculation device; and a pressure adjustor. The purge supply device may include a purge path connected to an intake path of an engine mounted on a vehicle, and be configured to supply evaporative fuel from a fuel tank to the intake path through the purge path. The exhaust gas recirculation device may include a circulation path connected to the intake path between a throttle valve and a first connecting position connecting the intake path and the purge path, and be configured to supply to the intake path a part of exhaust gas of the engine through the circulation path. The pressure adjustor may be disposed between the first connecting position and a second connecting position connecting the intake path and the circulation path, and be configured to adjust a pressure at the second connecting position.

In a case where a driving state is switched from a high load to a low load in a non-turbo charge region and an external EGR is stopped, at a timing T01 at which an EGR control valve (21) is closed, a valve overlap quantity between an intake valve and an exhaust valve is, as a low load transient time provisional value, controlled in a direction such that the valve overlap between the intake and exhaust valves is once contracted. Then, a target value of the valve overlap quantity between the intake and exhaust valves at a timing T21 preceded by a response time t of the variably operated valve mechanism (28) from a timing T31 at which the opening angle of the EGR control valve (21) is modified from the low load transient time provisional value to the target value at the time of the low load.

A method includes controlling an engine speed based on: intake manifold air temperature and/or intake manifold pressure one, or more, of the following data parameters: an engine load as a function of a fuel level, a fuel injecting timing, an intake oxygen concentration, a constituent concentration from the exhaust gas flow, an engine power, and an engine torque. The method also recirculates a portion of the exhaust gas flow to the combustion cylinders of the engine via a recirculation channel, as a function of intake manifold temperature and/or intake manifold pressure at which the engine is operated. An engine system, other methods, and a non-transitory computer readable medium encoded with a program, to enable a processor-based control unit to control aspects of the engine are also disclosed.

A method of controlling turbine efficiency in a turbo unit provided on an internal combustion engine includes providing a flow of gas in an area upstream a turbine at a direction different to the flow of exhaust gases in the same area, regulating the flow by a valve, and controlling the valve from a control unit having at least boost pressure and/or EGR flow as input parameters.

A method of controlling turbine efficiency in a turbo unit provided on an internal combustion engine includes providing a flow of gas in an area upstream a turbine at a direction different to the flow of exhaust gases in the same area, regulating the flow by a valve, and controlling the valve from a control unit having at least boost pressure and/or EGR flow as input parameters.

A low-pressure-loop EGR apparatus of an engine includes an EGR passage to allow part of exhaust gas discharged from a combustion chamber to return as EGR gas to the combustion chamber, and an EGR valve to regulate a flow of EGR gas in the EGR passage. This passage has an inlet connected to an exhaust passage downstream of a turbine and an outlet connected to an intake passage upstream of a compressor. In the intake passage, an intake bypass passage is provided to connect an upstream portion and a downstream part from the compressor. An ABV is provided in the passage. To remove EGR gas remaining in the ABV, one end of a residual gas removal passage is connected to the intake passage downstream of a throttle valve and the other end of the same passage is connected to the ABV.

A low-pressure-loop EGR apparatus of an engine includes an EGR passage to allow part of exhaust gas discharged from a combustion chamber to return as EGR gas to the combustion chamber, and an EGR valve to regulate a flow of EGR gas in the EGR passage. This passage has an inlet connected to an exhaust passage downstream of a turbine and an outlet connected to an intake passage upstream of a compressor. In the intake passage, an intake bypass passage is provided to connect an upstream portion and a downstream part from the compressor. An ABV is provided in the passage. To remove EGR gas remaining in the ABV, one end of a residual gas removal passage is connected to the intake passage downstream of a throttle valve and the other end of the same passage is connected to the ABV.

In a turbocharged, uniflow-scavenged, two-stroke cycle, opposed-piston engine, transient changes in engine operating conditions initiate modes of air handling operation during which reversal of EGR flow in a high pressure EGR loop of the air handling system is prevented by operating one or more air handling devices to increase resistance to exhaust flow in the engine.

A turbine (32) section of a turbocharger (30) includes a turbine wheel (37) disposed in a turbine housing (33), the turbine housing (33) defining a gas inlet (34), a volute configured to direct gas from the inlet (34) to the turbine (32) wheel, and a gas outlet. A rotary diverter valve (100, 200) is disposed in the gas inlet (34) upstream of the volute, and provides three modes of controlling exhaust gas flow about the turbocharger (30).