| 摘要 |
PROBLEM TO BE SOLVED: To expand an exhaust gas recirculable driving area so effectively and reduce in NOx by installing an exhaust turbine being driven by dint of exhaust gas and having more than two scrolls, and conducting the exhaust gas to a separate scroll of this exhaust turbine. SOLUTION: An exhaust manifold 12 of a multicylinder diesel engine 10 for a truck is halved by a partition wall 16 installed almost the central part in the engine longitudinal direction, forming two turbine upstream side exhaust passages 12f and 12r, and these passages 12f and 12r are connected to two separate scrolls 18f and 18r of an exhaust turbine 18. In succession, an EGR passage 28 is connected to an interval between the exhaust passage 12f and an inlet passage 24 at the compressor discharge side, and then an EGR valve 30 is installed in this EGR passage 28. On the other hand, a bypass passage 34 is installed in space between the exhaust passage 12f and an exhaust passage 20 at the exhaust turbine downstream side, a waste gate valve 36 is installed in this bypass passage 34. With this constitution, an EGR driving area is well expandible. |
