| 摘要 |
PURPOSE:To reduce the generation of white smoke and irritating smell by mounting a bypass section, which can introduce exhaust gas only on low speed or low load, to an exhaust main pipe between an outlet for a high-pressure stage supercharger and an inlet for a low-pressure stage supercharger. CONSTITUTION:A bypass section 21 is installed to an exhaust main pipe 17 mounted between a turbine outlet for a high-pressure stage turbine 6 and a turbine inlet for a low-pressure stage turbine 10, and a bypass changeover valve 18 is set up to a branch section from the exhaust main pipe 17 so that exhaust gas is introduced to the bypass section 21 only on low speed or low load. Exhaust gas is introduced to the bypass section 21, heated by a small-sized combustion device 19 and oxidized completely by a catalyst 20 for oxidation on low- speed or low-load operation. Oxidized exhaust gas is introduced to the low-pressure stage turbine 10, and discharged. Exhaust gas is not passed through the bypass section 21 and is forwarded to a supercharger through the exhaust main pipe 17 on high speed or high load. |
