摘要 |
In an internal combustion engine with a variable nozzle vane turbocharger, when the flow rate (VN passage flow rate) of exhaust gas passing through nozzle vanes has reached a spatial resonance region in an exhaust gas passage space between a turbine housing and a catalyst during acceleration, the flow rate is increased so that the spatial resonance region can be quickly passed. When the flow rate (VN passage flow rate) of exhaust gas passing through the nozzle vanes has reached the spatial resonance region during deceleration, the flow rate is decreased so that the spatial resonance region can be quickly passed. Such a control can reduce a period of time during which the frequency of pressure pulsation occurring at the rear ends of the nozzle vanes is amplified in the spatial resonance region, whereby noise caused by the pressure pulsation can be reduced. |