Gasoline Vehicle Catalytic Converters And Structural Optimization Of The Design Of Flow Field

Based on the comprehensive study on the flow field, pressure loss and construction design of three-way catalytic converter (TWC), and aimed at improving the performance of TWC and researching the flow field and pressure loss, the fluid and heat transfer models have been established with a computational fluid dynamics(CFD) code. The results of numerical simulation are agree with the testing ones. The effects of the velocity distribution uniformity on conversion efficiency and durability and pressure loss on engine power and fuel economy have been discussed. A simple arithmetic of the range of exhaust velocity is brought forward for optimum design of TWC of a domestic EFI engine. Initial and boundary conditions of TWC under all operating condition have been calculated. The effects of every structure parameter of monolith and TWC on velocity distribution and pressure loss have been discussed. Some advice is given for reasonable design of structure parameters. Further research of inlet diffusion header has been performed. Basic method of optimum design is summarized. A new type of inlet diffusion header and inlet little pipe is put forward, and the improvement of TWC performance is confirmed. It is proved in this paper that the application of CFD together with experiments is a time and energy saving means as well as a more reasonable and important one. According to the results in this paper, a better flow distribution and lower pressure loss can be achieved so that the less negative effect on power and fuel economy, the improved converter efficiency, the quickened light-off and the lengthened life of TWC are followed if the appropriate structures of TWC are adopted. This indicates that this paper is of great theory significance and practical value in the study of lower exhaust and energy saving.