进、排气背压对涡轮增压柴油机工作过程影响的研究

本研究在不同进、排气背压下,测定了柴油机示功图,进、排气管温度及压力,柴油机输出功率和排气烟度等参数,在此基础上计算了柴油机放热率,分析了进、排气背压变化对柴油机放热率的影响。结果表明,进气背压变小后,柴油机燃烧持续期变长,热量利用率低;排气背压增大后,柴油机燃烧不充分,排气烟度大;排气背压变大后,涡轮增压器工作环境差,柴油机进气压力也相应降低。

Study on Influence of Inlet or Exhaust Back Pressure to Combustion Process Turbocharged of Diesel Engine

In different inlet or exhaust back pressure conditions,indicator diagram,temperatures and pressures of air inlet pipe and air exhaust pipe,output power and exhaust smoke density were measured.Heat release rate was calculated and influence of inlet or exhaust back pressure to heat release rate was analyzed.When inlet back pressure became lower,combustion duration became longer and heat energy utilization rate became lower.When exhaust back pressure became higher,fuel combusted insufficiently and exhaust smoke density became higher.Turbocharger working condition changed and inlet air pressure became lower.