Study On CFD Technology Applying To Catalytic Converter

Presently, catalytic converter is the most effective equipment to emission control, which can reduce harmful ingredient of automobile emission. With the standard for discharge becoming stringent, the request of catalytic converter's performances also become rigid. Research and development of catalytic converter has become a heated topic. Test is a traditional method, which can give necessary message to the research and development of catalytic converter, but it can't show the heat and mass transfer and internal flow in catalytic converter. With the development of computer technology and the maturity of numerical model of catalytic converter, another method-- numerical simulation is available. In this paper, catalytic converter is studied with numerical simulation method and Fluent is used which is a kind of CFD software. It can simulate heat transfer and internal flow in complex shape channel. A three-way catalyst including Pd is evaluated using test method and its light-off course is simulated. The result shows the change of its temperature field and concentration field in light-off course. Flow velocity distributing in monolith gives great effect on transform efficiency and light-off character and life of catalytic converter. Press losing can influence dynamics of engine and economy of fuel. So improving flow performance of catalytic converter is very important, which is one goal to catalytic converter optimal design. Through the steady test of catalytic converter, what different angles of expanding tube influence on catalytic converter is analyzed, and then flowing field is simulated. Flow velocity distributing of different expanding tubes is showed in simulation result, which is consistent with test result. It is proved that CFD technology can be used in catalytic converter optimal design. An optimizing project of an asymmetry catalytic converter is analyzed using CFD technology. Effect of different incline angle of inlet tube and diffuser tube on flow performance is analyzed and the best parameter of its structure is found. Special in the study: During the process of building the model, it is considered fully how the reaction heat influences the temperature of monolith, which makes the model consistent with the fact. When interior flow distribution is analyzed, the computational method of flow distribution according with numerical model is deduced. During the process of solving the model, the model is solved by interface of CFD software and "Newton-Raphson" arithmetic with "dual-cell" meshes technology. 3. Through the compare of test result and simulation result, it is proved that CFD technology can be used in research and development of catalytic converter.