Close-Coupled Converter Modeling with a Thinwall Substrate for a Gasoline Engine

On a 1.0 liter engine, the underbody standard ceramic converter was replaced by a close-coupled converter with a ceramic thinwall substrate. The goals were to meet future emissions regulations (Euro 3) and to reduce light-off time maintaining engine performance.

The design was conducted based on modeling data. Converter back pressure, heat-up, conversion efficiency as well as the converter external temperatures were predicted. The exhaust gas flow velocity was analysed with CFD modeling to check the distribution of the exhaust gas through the manifold geometrie and through the substrate.