大缸径船用柴油机部分预混压燃的试验研究

以某中速船用柴油机为研究对象，试验研究了基于两次喷射技术对于船用柴油机性能和燃烧特性的影响。结果表明，基于两次喷射技术可以实现大缸径船用柴油机PPCI燃烧模式，两次喷射的预喷正时、预喷油量及燃油喷射压力对于PPCI燃烧过程有明显影响。通过两次喷射策略在单缸机试验研究，可以确定适用于大缸径船机的PPCI燃烧的燃油喷射控制策略：在Pe0.3MPa下，采用喷射压力105 MPa +预喷时刻20°CA BTDC +预喷油量20%，在Pe0.6MPa时，喷射压力120 MPa +预喷时刻35°CA BTDC +预喷油量28%的喷油策略，可以实现较为理想的部分预混均质压燃PPCI燃烧，燃油消耗率可改善3.1%~6.2%，soot排放降低51%~62%，压升率降低58~70%。本文研究为船用柴油机满足未来EEDI法规及低噪声设计提供有效支撑。

Experiment Investigate of PPCI Combustion of Marine Diesel Engine

Based on the medium-speed marine diesel engine, the experimental study were carry out to find influencebetween two stage injection and the combustion characteristics. The test results show that,for large bowl marine diesel engine, two stage injectioncan realized the PPCI(Partially Premixed Compress Ignition) at part load condition. And the key factors of PPCI were pilot inject timing, pilot inject mass and inject pressure. It can be concluded that through the refined strategy of two stage inject, the PPCI combustion can be realized at Pe0.3 MPa and Pe0.6 MPa. The post-optimized strategy of two stage injection at Pe 0.3MPashould be 105MPa inject pressure, 20°CA BTDC pilot inject timing,20% pilot inject mass at 0.3MPa.And the post-optimized strategy of two stage injection at Pe 0.6MPa should be 120MPa inject pressure, 35°CA BTDC pilot inject timing,28% pilot inject mass. And profit from the PPCI combustion, the BSFC can be reduced 3.1%~6.2%,the soot emission can be reduced 51%~62%,the rate of pressure raise can be reduced 58~70%.And the investigation of this paper can be valuable for the design of marine diesel engine,with the aim to satisfy the future requirement of EEDI and low combustion noise.