基于DoE方法的二冲程点燃式煤油发动机爆震试验

Knock experiments for two-stroke spark-ignition aviation kerosene engine based on DoE method

针对二冲程航空煤油发动机单参数调整喷油量或点火提前角来抑制发动机爆震,提出了一种喷油-点火协同控制的发动机爆震抑制策略,以一台二冲程点燃式发动机为对象,利用一维性能仿真计算平台对其建模与仿真分析,根据试验设计方法(design of experiment,DoE)得到基于喷油-点火协同控制策略下的喷油量和点火提前角的MAP图,并开展了试验研究。结果表明:在转速为4800 r/min时,相比于单参数控制点火提前角抑制煤油发动机爆震,采用优化策略后发动机爆震燃烧得到有效抑制,油耗率小幅度增加,功率损失减小且排气温度显著降低,并且在不同负荷下的发动机功率恢复最低能够达到汽油机的88.3%;在转速为5000~6500 r/min、全负荷工况下,发动机功率恢复最高能够达到汽油机的96.2%,排气温度控制在475℃以内,能够有效改善发动机性能。

In considering the deficiency of adjusting fuel injection amount or ignition advance angle to suppress knock on two-stroke kerosene engine,the coordinated injection-ignition control strategy for suppressing engine knock was proposed.A two-stroke spark ignition engine was taken as the test engine for comparative study,and its modeling and simulation analysis were carried out by using one-dimensional simulation platform.The MAPs of fuel injection amount and ignition advance angle were obtained by the method of design of experiment(DoE)after adopting the coordinated control strategy.The corresponding experimental investigations were conducted.The results showed that,at engine speed of 4800 r/min,compared with the single parameter of adjusting ignition advance angle to suppress knock intensity of kerosene engine,the optimized strategy was more effective.The specific fuel consumption showed a modest increase with reduced power loss and decreased exhaust temperature.The power recovery of kerosene engine can reach at least 88.3% of the burning gasoline at different loads;meanwhile,the power recovery can reach 96.2% under the condition of full load at engine speeds of 5000—6500 r/min,and the exhaust temperature can be controlled within 475℃,effectively promoting the performance of kerosene engine.