| 摘要:为了满足内河Ⅱ阶段排放标准，更好地实现减碳战略目标，对6CS21船用柴油机进行甲醇燃料改装并开展整机试验。研究25%负荷下的甲醇替代率和甲醇喷射时刻对大缸径船用中速机性能、燃烧和排放特性的影响。结果表明在25%负荷下，10%替代率油耗水平较低，80%替代率排放和热负荷较低。将柴油喷射正时固定为上止点前10°，研究发现：当甲醇喷射时刻晚于柴油喷射时刻，为上止点前6°时，油耗水平较低，甲醇喷射时刻越晚热负荷越高；当甲醇喷射时刻早于柴油喷射时刻，为上止点前16°时，油耗水平较低，甲醇喷射时刻对热负荷影响很小。 |
| 关键词: 船用中速机 甲醇 替代率 喷射正时 |
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| Effect of Methanol Substitution Rate and Injection Timing on the Performance of Direct-Injection Methanol Engine |
| JIANG Yuqi,YAN Ping,GUO Lijun,MA Yue,MAN Zhongguo |
| Shanghai Marine Diesel Engine Research Institute， Shanghai 201108， China |
| Abstract:In order to meet China Ⅱ emission regulations and better achieve the goal of carbon reduction，the 6CS21 marine diesel engine was retrofitted for using methanol fuel and the engine test was completed to study the effect of methanol substitution rate and methanol injection timing on the performance，combustion and emission characteristics of large-bore marine medium-speed engine at 25% load.The results show that at 25% load，the fuel consumption is low at 10% substitution rate and the emission and heat load are low at 80% substitution rate. Set the diesel injection timing at 10° before the dead center（BTDC），it is found that ：When the methanol injection timing is later than diesel injection timing，and is at 6° BTDC，the fuel consumption is low，the later the methanol injection timing is，the higher the heat load；when the methanol injection timing is earlier than diesel injection timing，and is at 16° BTDC，the fuel consumption is low，the methanol injection timing has little effect on the heat load. |
| Key words: medium-speed marine engine methanol substitution rate injection timing |
