| abstract |
An object of the present invention is to reduce particulate matter, number of particles and unburned HC in an exhaust flow by increasing residual gas and increasing the temperature in a cylinder. Plasma actuators (23A, 23B, 23C, 23D) of an internal combustion engine (1) are provided on at least one of an intake port (7) and an exhaust port (8). The plasma actuators 23A, 23B, 23C, and 23D generate at least one of an airflow that faces the intake main flow 36 and an airflow that faces the exhaust main flow 38 when the internal combustion engine 1 is not warmed up, and increases the residual gas in the cylinder 2. . Thereby, since the temperature in the cylinder 2 rises, the injected fuel is easily vaporized, and is difficult to adhere to the cylinder inner wall and the piston crown surface. Therefore, the particulate matter, the number of particles and the unburned HC in the exhaust stream 38 are reduced. [Selection] Figure 1 |