PACCAR

Defining DE-Sulfation SCR Behavior

Diesel engine aftertreatment systems architecture will change as a result of upcoming stringent Ultra Low NOx emission regulations in the US. A close coupled (downstream turbine) SCR is under investigation but is exposed to Sulphur from the fuel and oil reactants. This student team worked to define accurate physics / reaction rate-based models to simulate Sulphur loading and release behavior as a function of key system parameters such as engine flow, exhaust temperature and exhaust composition. The team produced detailed design and control rules to implement SCR in the proposed configuration without losing efficiency over time due to Sulphur poisoning.