Zero-Delay Light-Off - A New Cold-Start Concept with a Latent Heat Storage Integrated into a Catalyst Substrate

This study aims at a new concept for a fast catalyst light-off in combining a latent heat storage with a catalyst. The arrangement of a latent heat storage device into the exhaust system offers significant benefits for the catalyst light-off. Different arrangements have been examined.

The first arrangement, called the sequential arrangement, comprises a latent heat storage device and a subsequent catalyst. This offers a significantly faster heat up of the catalyst compared to the standard arrangement. By that emissions during the cold start phase can be significantly reduced. The setup of the latent heat storage device is designed for a high heat transfer between storage material and the exhaust gas.

A second integrated arrangement of a latent heat storage and a catalyst into one common substrate has also been set up and investigated. The main advantage of this arrangement is that the catalyst itself is kept on its operation temperature during the engine off time. Thereby, with the start of the engine the catalyst shows an immediate light-off without any delay. So CO and THC are converted from the very beginning of the start of the engine.