甲醇汽油掺混比对转子发动机性能的影响研究

Study on the influence of methanol gasoline mixing ratioon the performance of Wankel engine

甲醇有着含氧量高、燃烧性能良好和排放清洁等特点,被认为是理想的发动机替代燃料。以一款周边进气转子发动机为研究对象,提出通用的等效方法,在GT-POWER中建立等效往复式三缸四冲程发动机仿真模型,并对仿真结果进行对比验证。在此基础上,研究甲醇替代比对转子发动机燃烧过程和性能的影响规律,研究结果表明:汽油中掺混甲醇可以提高混合气燃烧速率,可使得转子发动机的缸压提高并且燃烧相位提前。在甲醇掺混比低于50%时,随着掺混比增加,转子发动机性能提升明显,缸压峰值对应的曲轴转角接近上止点,发动机功率和扭矩较纯汽油分别提升13.6%和12.8%。在甲醇掺混比高于50%时,随着掺混比的增加,发动机燃烧相位过于提前,压缩负功增加,发动机动力性提升效果降低,在M100时发动机功率提升仅为5.9%。研究结果可为转子发动机使用甲醇燃料以提升性能提供一定参考。

Methanol is considered an ideal alternative fuel for engines due to its high oxygen content,good combustion performance and clean emissions.Taking a gasoline rotary engine as the research object,and the simulation results of the model are compared and verified by using the test results.On this basis,the influence of methanol substitution ratio on the combustion process and performance of rotary engine is studied,and the following results are obtained:The mixing of methanol in gasoline can increase the combustion rate of the mixture,increase the cylinder pressure of the rotary engine and advance the combustion phase.When the methanol mixing ratio is low,the performance of the rotary engine is significantly improved,the crankshaft angle corresponding to the peak of the cylinder pressure is close to the TDC,and the engine power and torque are increased by 13.6%and 12.8%compared with pure gasoline.When the methanol mixing ratio is high,the engine combustion phase is too advanced,the compression negative work increases,the engine power improvement effect is reduced,and the engine power increase is only 5.9%when M100 is used.