对置活塞二冲程汽油机多点点火燃烧特性研究

Research on Multi-Ignition Combustion Characteristic of Opposed-Piston Two-Stroke Gasoline Engine

中文关键词: 对置活塞二冲程汽油机  燃烧过程  多点点火

英文关键词: opposed-piston two-stroke gasoline engine  combustion process  multi-ignition

中文摘要:

      由于取消了气缸盖，对置活塞二冲程（OP2S）汽油机的火花塞只能布置于气缸侧壁。因此在单火花塞点火时，缸内火焰传播不对称，导致OP2S汽油机具有较明显的爆震倾向。为了有效地抑制爆震的发生，利用三维CFD软件对OP2S直喷汽油机在不同火花塞数目下缸内的燃烧过程进行了数值仿真，并结合试验研究了火花塞数目对混合气燃烧特性的影响，分析了不同火花塞数目对缸内燃烧压力、燃烧持续期及燃烧放热率的影响规律。研究结果表明，增加火花塞数量可以有效改善缸内的燃烧情况，而对侧布置双火花塞的布置形式为最佳方案。

英文摘要:

      The spark plug of an opposed-piston 2-stroke (OP2S) gasoline engine have to be set up in the cylinder wall due to the cancellation of the cylinder head. Therefore, when the single spark plug ignites, the flame propagation in the cylinder is asymmetric, which may lead to an knock occurred for the OP2S gasoline engine. To inhibit knock occurred, the numerical simulation of the combustion process were carried out in an OP2S direct injection gasoline engine’s cylinder with different spark plug numbers by using three-dimensional CFD software. It was investigated that the dependence of combustion characteristics of mixed gas on spark plug number based on experimental results. The combustion pressure, combustion duration and combustion heat release rate in cylinder to different spark plug numbers influence rule were also summarized. The results indicate that the increase the number of spark plugs can effectively improve the combustion in the cylinder, and placing the double spark plug on the sides is the optimal solution.