| 摘要 |
A method of operating a four-stroke cycle Diesel engine supercharged by an exhaust gas-driven turbocompressor with valve timing comprising a partial overlap of the opening periods of the exhaust and intake valves, with early intake closure and partial exhaust closure for the major part of the intake step followed by partial reopening of the exhaust and its final closure near bottom dead center after closure of the intake valve. At low and medium engine powers part of the supercharged intake air is bypassed to an end of an exhaust manifold, thereby increasing the cylinder filling factor and combustion air excess and substantially reducing exhaust valve temperature in the mid-power operating range of the engine. |
