Exhaust Pipe of a Passenger Car

In the regulated catalytic converter located in the exhaust pipe of a passenger car, an exothermal catalytic reaction occurs. The quantity of heat produced during this process strongly depends on the flow velocity in the converter. Because overheating might damage the converter, the thermal load should be even to improve its lifetime.  In order to obtain this thermal load, the flow in the converter must also be as even as possible. The computational calculation is complicated as the installed configuration consists of amorphous pipes and the catalytic body of the converter is made of a material with porosity dependent on flow direction.

Work included:

• Direct implementation of the CAD model
• Consideration of an approximately anisotropic porous zone with a compressible medium
• Introduction of locally trans-sonic flow
• Validation by means of available measurement data