摘要
对混合式MSEM增压系统排气管流动特性进行了研究。研究表明:由于发火不均匀,混合式MSEM增压系统排气管内压力波一边高,一边低,呈现出与常规增压系统不一样的形态;混合式MSEM增压系统混合管中间截面处的气体流速约在±50m/s的范围内喘动,会增加动量的掺混损失。为了提高MSEM增压系统柴油机的性能,对MSEM+Scaby系统进行了研究。研究表明:混合式MSEM+Scaby系统的改动少,可使各缸扫气系数均匀、各缸排温差小、平均扫气系数大、排温降低,有进一步提高功率的潜力。
Flow characteristics of mixed MSEM turbocharging system are studied. The results show that: Because firing order is not homogeneous, the pressurewave in exhaust pipe ofmixed MSEM system is high atone side and low at another side, and it is different from that of common turbocharging systems. The velocity at the middle section of mixed MSEM system exhaust pipe is about -50m/s to 50 m/s, so it will cause momentum loss. In order to improve the performance of mixed MSEM diesel engine, MSEM+Scaby system is studied. The results show that: the change on mixed MSEM+Scaby system are little; It can make scavenging coefficients homogeneous, discrepancy of each cylinder exhaust temperature small, mean scavenging coefficient large, exhaust temperature before turbine low, and thus has the potentials to improve engine performance further.
出处
《柴油机》
2004年第5期16-19,共4页
Diesel Engine
