三元催化转换器改进及其对发动机性能的影响

Research on the influence of the improved three-way catalytic converter to engine performance

对应用于GW491QE型汽油发动机的三元催化转换器进行了改进,载体采用球形端面,增加了载体孔数,壳体前端锥采用两个扩张角,壳体两端采用缩颈处理。改进后的三元催化转换器增加排气气流进入载体前流速的均匀性,充分发挥了整个载体的转换效率,有效防止了衬垫过早脱落,使三元催化转换器的使用寿命得到提高。试验结果表明,改进后的三元催化转换器,对发动机的动力性和经济性影响较小,对HC、CO和NOx的转换效率较高,三元催化转换器与该发动机在动力性、经济性和排放性方面达到良好匹配。

The structures of three-way catalytic converter used in GW491QE engine are improved. The front globose end surface is used in the carrier of three-way catalytic convener, and the number of pores in the carrier is increased. The front cone of the shell has two expanding angles. Two-terminals of the shell are necked. After the structures of three-way catalytic converter are improved, the speed of gas becomes more uniform before entering the carrier. So the conversion efficiency of the whole carrier is brought into full play. The necked two-terminals of the shell can prevent the end surface of substrate from coming off early. The service life of the three-way catalytic convener will be improved. The experiment result shows that the improved three-way catalytic converter has a little influence of the power and fuel economy of the engine. It has high conversion efficiency in reducing HC, CO and NOx emission. The three-way catalytic converter matches well with the engine in the power, fuel economy and emission performance.