| 摘要:为了探究燃气喷射参数对船用低压双燃料主机燃气-空气混合效果的影响，改变主机燃气配气正时，通过数值计算的方法对比不同燃气喷射时刻下的缸内混合气发展趋势，同时结合台架试验数据进行分析。分析结果表明:燃气喷射正时推迟，活塞头附近燃气含量增大，气缸盖和排气阀附近燃气含量降低，燃气上部会形成一层“气垫”，阻止燃气与高温零部件接触而发生早燃；同时，随着喷射正时推迟，甲烷在压缩冲程的物理扩散逃逸问题得到缓解，但活塞头附近燃气集聚，导致活塞头热负荷增加。 |
| 关键词: 低压双燃料主机 配气正时 甲烷 逃逸 |
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| Influence of Gas Injection Timing on Gas-Air Mixing Effect ofTwo-Stroke Low-Pressure Dual Fuel Engine |
| Wang Lei,Su Xiangwen,Xu Zhaogang |
| CSSC-MES Diesel Co.,Ltd., Shanghai 201306 |
| Abstract:In order to explore the influence of gas injection parameters on the gas-air mixing effect of marine low-pressure dual fuel engine, by changing the gas injection timing of the main engine, the development trend of in-cylinder mixture at different gas injection times was compared by numerical calculation, and analyzed in combination with the bench test data. The results show that when the gas injection timing is delayed, the gas content near the piston head increases, the gas content near the cylinder head and exhaust valve decreases, and a layer of "air cushion" will be formed on the upper part of the gas to prevent early combustion due to the contact between the gas and high-temperature parts. At the same time, with the delay of gas injection timing, the physical diffusion and escape of methane in the compression stroke is alleviated, but the gas accumulation near the piston head will increase the heat load of the piston head. |
| Key words: low pressure dual fuel main engine gas injection timing methane slip |
