Technical Paper
Systems Durability of a Ceramic Racetrack Converter
1991-10-01
912371
The long-term durability of a ceramic racetrack converter is examined using the systems approach. Each of the converter components is characterized with respect to its behavior under simulated mechanical and thermal loads. In particular, the impact of three different washcoats on key physical properties, and the load vs. deformation characteristics of three different insulation mats are examined from mechanical and thermal durability point of view. Similarly, the can deformation at elevated temperature is taken into account to ensure adequate mounting pressure on ceramic monolith under all operating conditions. The temperature distribution at the midbed of the catalyst during engine dynamometer testing, together with the component properties data, are then used in a finite element model to compute thermal stresses in the monolith as function of engine load and speed.