可变气门定时(VIC)与增压器改造对低负荷下柴油机的性能的改善

Variable valve timing (VIC and supercharger) improved performance of diesel at low load

VIC-可变进气阀门正时,在四冲程柴油机负荷低于50%时起作用。通过延迟关闭进气阀门来增加气缸燃烧室内进气量,从而降低进气压缩温度和燃烧后的废气温度。定压涡轮增压在部分负荷运行时性能较差,过量空气系数低,排烟温度高,造成增压器进、出端温度过高,且影响进气质量,同时排烟温度高使柴油机机件的热负荷增加,缩短柴油机机件使用寿命。

The VIC-variable intake valve timing is active when the four-stroke diesel engine load is less than 50%.Increase the air intake in the cylinder combustion chamber by delaying closing the intake valve,thus reducing the air intake compression temperature and the combustion exhaust gas temperature.Fixed pressure turbocharging has low performance in partial load operation,low excess air coefficient,high smoke exhaust temperature,causing high temperature of the supercharger inlet and exit end,and affects the air intake quality.Meanwhile,the high smoke exhaust temperature increases the heat load of diesel components and shortens the service life of diesel engine.