CFD在车用催化转化器结构优化设计中的应用

本文用当量连续法建立了蜂窝载体的流体动力学模型，并用ＣＦＤ软件对两个不同的结构扩张管的以载体催化转化器的流场进行了三维稳态流动数值模拟，模拟结果显示：在相同气流条件下，短扩张管较长晚容易造成气流在锥形管壁面出现分离并产生较强的扰动，使局部流动损失增大同时使得载体前气流速度分布更加不均匀；此外，载体之间的缝隙空间使第二块载体的速度分布更均匀，模拟结果来催化转化器的优化设计提供了依据。

Application of CFD to the Optimal Design of Automotive Catalytic Converters

In this paper, the mathematical model of flows in the substrate was established by using the equivalent continuum approach, and three-dimensional numerical simulations of the steady flows in the dual substrate catalytic converters with different diffuser configurations were performed. The computing results show that the short conical diffuser is prone to cause the flow to separate from the wall and produce stronger turbulent than the long diffuser under the same flow conditions. The separated flows will increase the pressure losses and result in more nonuniformity of the velocity distribution in front of the first substrate. In addition, the gap between two substrates makes the velocity distribution of the second substrate more uniform. The simulation results provide a basis for optimal design of the catalytic converters.