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为了了解异步点火相位对二冲程航空活塞发动机燃用煤油时的爆震影响问题,使用Fire软件建立了发动机燃烧室的计算模型,并通过试验验证了该模型,研究了异步点火相位对发动机缸内燃烧以及火焰面密度分布、爆震强度的影响等.结果表明:在转速为5000r/min、全负荷工况、混合气当量比为1.1、点火能量为35.64mJ条件下,当其中一个火花塞点火时刻固定在上止点前曲轴转角为29°,另一个火花塞相对其分别提前曲轴转角为1°,3°,5°时点火,随着双火花塞异步点火相位差的增大,缸内平均压力、放热率及累积放热量均呈现减小的趋势,两个火花塞附近的湍动能增大,火焰传播速度加快,火焰发展期缩短,爆震强度表征物的浓度逐步减小,二冲程煤油发动机爆震发生的倾向减小.
In order to understand the influence of asynchronous ignition phase on knocking of two-stroke aeronautic piston engine when it burns kerosene, the calculation model of engine combustion chamber is established by using Fire software. The model is validated by experiments and the influence of asynchronous ignition phase on engine cylinder Combustion and flame surface density distribution, the influence of the detonation intensity, etc. The results show that when the ignition speed is 5000r / min, the full load condition, the mixture equivalence ratio is 1.1 and the ignition energy is 35.64mJ, when one of the spark plug ignition time Fixed before the top dead center crankshaft rotation angle of 29 °, the other relative to their pre-crankshaft crankshaft angle of 1 °, 3 °, 5 ° ignition, with double spark plug asynchronous ignition phase difference increases, the average cylinder pressure, The heat release rate and the cumulative heat release showed a decreasing tendency. The turbulent kinetic energy near the two spark plugs increased, the flame propagation speed accelerated, the flame development period shortened, and the concentration of detonation intensity indicator gradually decreased. The two-stroke kerosene engine explosion The tendency of earthquakes to decrease.