为满足欧Ⅵ排放法规，本文首先分析了欧Ⅵ主流的技术路线的优缺点，并选择了一种比较稳妥的技术路线进行研究，同时确认了发动机本体排放开发目标。然后在一台重型共轨柴油机基础上采用了一种冷却EGR、高喷射压力（最高喷射压力2500bar）以及可变截面增压（VGT）的燃烧技术进行试验研究。结果表明，通过正交优化VGT和EGR阀位置开度可以有效实现最佳EGR率和空燃比控制，显著降低NOx排放；采用关键正交组合优化方法，确认了最佳油嘴和喷油器垫片的组合；高喷射压力技术可以有效改善NOx和PM的折衷关系，同时改善了燃油经济性。在燃烧系统优化的基础上，最终WHSC的测试结果满足了发动机本体排放开发目标，最低比油耗达到了188 g/kW.h。试验结果说明该路线具备满足欧Ⅵ排放的潜力同时又具有较好的燃油经济性。%To meet Euro-Ⅵ standard, firstly, current Euro-Ⅵ technology road map were analyzed and a Reliable technology was choosed for research. Also Based engine emission target was setting. Then, a combustion technology research on reduction emission by cooling EGR system, variable geometry turbocharger(VGT) and high injection pressure system was conducted by a heavy-duty common rail diesel engine. Results show that EGR ratio and air/fuel ratio can be best controlled by an orthogonal optimization method for adjusting EGR valve position and VGT position. An orthogonal optimization method also was used for choosing best injector and gasket. Increasing injection pressure can effectively improve the trade-off relationship between NOx and smoke emission, also fuel economy was improved. Base on optimization combustion system, WHSC test results shows that emissions can meet development target and best BSFC can reach 188 (g/kW.h). It shows that this combustion technology has great potential for meeting Euro-Ⅵstandard and better fuel economy.
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