Abstract
In the near future the effort on the development of exhaust gas treatment systems must be increased to meet the stringent emission requirements. On the one hand side the complexity exhaust lines will increase dramatically due to the use of new catalyst and filtration units (Diesel Particle Filters), on the other hand side emission control is merging with powertrain management. If the relevant physical and chemical models are available, the numerical simulation is an important tool that supports the design f these systems. The new models implemented into the CFD Code FIRE allow to cover the full range of applications in this area. The theoretical background, the modeling strategies and capabilities are presented. The transient heat-up a close coupled catalyst is shown as an example.