车用催化器结构因素对流速分布的影响

车用催化器的速度分布特性对催化器和发动机的性能有很大影响。本文在气道稳流实验台上利用三孔结托管测量了不同结构催化器的速度分布，并进行了细胞致的对比分析。研究表明：张张角越大，流速分布越不均匀，但锥角超过一定值后，对流速分布的影响减弱；斜扩张管催化器的速度分布性相同长度直扩张管催化器；球形端面载体的速度分布均匀性要好于常平端面载体；载体安装位置扩张管越远，流速分布越均匀。

The Effects of Structure of Automotive Catalytic Converters on its Flow Distribution

The flow distibution of automotive catalytic converter has a significant effect on the performance of catalysts and engines. In this paper the axial velocities of the catalytic converters with variable structure and configuration have been measured by a three-hole pilot tube on a steady flow rig and experimental results are analyzed in detail. The results show that the velocity uniformity decreases as cone angle of the diffuser increases, but the effect on velocity distribution will become weak when the angle is krger than certain degree. The inclined diffuser has a better uniformity than conventional conical diffusers with the same length. The substrate with spherical has a better uniformity than the conventional flat end substrate. The farther the substrate is away from the diffuser, the more uniform the velocity distribution inside the substrate is.