Optimization of Catalytic Converter Design to Improve Under-Hood Thermal Management

The Catalytic Converter along with the inlet pipe and heat shields are part of the exhaust system that emits powerful heat to the surrounding components. With increasing need for tight under-hood spaces it is very critical to manage the heat emitted by the exhausts that may significantly increase temperature of surrounding components. In this paper a design methodology for catalytic converter has been applied which optimizes the design of the catalytic converter to reduce the surface temperature. The exhaust surface temperature is simulated as a function of time to account for transient effects. The simulation also considers various duty cycles such as road load, city traffic and grade driving conditions. To control the heat output of the exhaust system to the surrounding components different materials and properties of catalytic converter have been considered to reduce radiative heat transfer. The most influential design factors for the catalytic converter which affect the surface temperature of the exhaust system have been identified with this process. The paper summarizes the optimization steps necessary to meet the optimal functional goals for the vehicle as mentioned above. Taguchi's Design for Six Sigma (DFSS) methods have been employed to conduct this analysis in a robust way.