中文摘要：

以某4缸增压直喷柴油机为样机，利用专业试验台架，在优化喷油提前角和EGR阀开度的前提下，联合利用氧化催化器（DOC）及微粒氧化催化转化器（POC）技术对柴油机尾气排放进行了试验研究，并总结了DOC和POC技术对柴油机排放的影响规律。试验结果表明，通过优化喷油提前角及EGR阀开度，并且选择正确的DOC与POC的布置形式，完全可以使柴油机尾气排放达到欧Ⅳ排放标准。

英文摘要：

Taking a 4-cylinder turbocharged DI diesel engine as the prototype, the diesel engine exhaust emission was researched on the premise of optimized injection timing and EGR opening on a special test bench by using diesel oxidation catalyst （DOC） and particulate oxidation catalyst （POC） technology. Then the influencing rules of DOC and POC on diesel engine emission were summarized. The result shows that the exhaust emission can reach Euro Ⅳ standard by selecting the appropriate lo cation of DOC and POC under the condition of optimizing injection timing and EGR opening.