进气节流对车用柴油机性能影响的试验研究

Effects of Intake Throttling on Performance of Vehicle Diesel Engine

为了满足DPF主动再生温度需求,研究了进气节流对柴油机性能的影响。在某款高压共轨柴油机进气道加装电子节气门,在转速为1600 r/min和2000 r/min时,选取低、中、高三个典型负荷,研究不同节气门关度下进气流量对柴油机过量空气系数、燃油消耗率、排气温度及排放特性的影响。试验结果表明:随着节气门关度的增大,发动机过量空气系数逐渐减少,在低速中负荷条件下过量空气系数最大能降低14%;燃油消耗率随着节气门关度的增加呈现先下降后上升的趋势;进气节流可以显著提高排气温度;进气节流增加会导致CO排放和烟度的恶化,在较小的节气门关度下,THC和NO_(x)排放有所改善。

In order to meet the requirement of DPF active regeneration temperature,the effect of intake throttling on performance of diesel engine was studied.In a high-pressure common rail diesel engine with inlet pipe equipped with electronic throttle,the effects of intake flow on excess air coefficient,specific fuel consumption,exhaust temperature and emission characteristics were studied under low,medium and high loads at 1600 r/min and 2000 r/min based on different throttle close degrees.The test results show that the excess air coefficient decreases gradually with the closing of throttle and drops by 14%at most under the condition of low speed and medium load.The specific fuel consumption first decreases and then increases with the increase of throttle close degree.The intake throttling can significantly increase the exhaust temperature.In addition,the increase of intake throttling will lead to the deterioration of CO and soot emissions,and THC and NO_(x)emissions will improve at a small close of throttling.