| 摘要 |
<P>PROBLEM TO BE SOLVED: To efficiently use catalysts as a whole so that the deviation of the flow velocity of exhaust gas produced by the curved part of an exhaust passage on the upstream side of the catalyst does not partially destroy or deteriorate the catalysts. <P>SOLUTION: In this internal combustion engine, an SOx trap catalyst 24 for capturing SOx is disposed in the engine exhaust passage, and an NOx storage/reduction catalyst 25 is disposed in the exhaust passage on the downstream side of the SOx trap catalyst 24. The engine exhaust passage has the curved part. Since the exhaust gas passes through the outer side of the curved part, the deviation occurs in the flow velocity of the exhaust gas in the exhaust passage, and the exhaust gas in that state flows to the SOx trap catalyst 24. Therefore, partial deviation occurs in the inflow amount of the exhaust gas. A flow velocity control valve 61 is disposed in the exhaust passage where the exhaust gas flows on the outer side of the curved part and the flow velocity is increased on the upstream side of the SOx trap catalyst 24, and controlled to the position predetermined according to the average flow velocity Vav of the exhaust gas. Therefore, the flow velocity control valve so controls the flow of the exhaust gas as to uniformly enter the SOx trap catalyst 24. <P>COPYRIGHT: (C)2009,JPO&INPIT |
