柴油机可调两级增压系统变海拔稳态调节特性研究

Steady Regulation on Plateau for Diesel Engine with Two-stage Turbocharging System

利用GT-Power软件建立某V型柴油机仿真模型,并进行了可调两级增压系统的匹配。模拟计算了不同海拔条件下发动机全工况运行时高压级涡轮旁通阀开度对燃油消耗率的影响。结果表明,高压级涡轮旁通阀开度是通过发动机指示效率与泵气损失间接影响燃油消耗率。同一工况下,发动机燃油消耗率按其主要影响因素的不同分为示效率主导区、泵气损失主导区以及两者综合影响区。且随着海拔的升高,影响发动机燃油消耗率的指示效率主导区域扩大,泵气损失主导区域减小。最后,以最佳燃油经济性为指标,得到变海拔全工况下涡轮旁通阀最佳阀门开度。

The model of a V-type diesel engine was built with GT-Power and was matched with the adjustable two-stage tur-bocharging system .The effect of bypass valve opening for high pressure turbine on fuel consumption rate was calculated at dif-ferent altitudes .The results show that the bypass valve opening has an indirect effect on fuel consumption rate through engine indicated efficiency and pumping loss .Under the same condition ,the regulation regions are divided into engine indicated effi-ciency dominant region ,pumping loss dominant region and their joint working region according to the main influencing factors . Moreover ,the engine indicated efficiency dominant region expands and the pumping loss dominant region shrinks with the rise of altitude .Finally ,the best valve opening for engine full working conditions at different altitudes is acquired based on the best fuel consumption rate .