Combined Virtual and Experimental Approach to Develop Highly Efficient Metallic Catalyst for New World Wide Emission Legislation

The market penetration of Battery Electric Vehicles (BEV) in Europe is not following the foreseen scenario. This is related to several factors, such as uncertainty of the second-hand value of BEV, real driving range under cold conditions and availability of charging stations. Even if the European Community is still planning a full ban of Internal Combustion Engines (ICE) by 2035. In the rest of the world a more technology neutral approach is being pursued with car manufacturers developing different powertrain architectures, from mild- to full-hybrid and Range Extenders (REEX). In this context the different emission regulations, and the wide range of powertrain architectures, the focus of the development will be the increase of catalyst efficiency without any big impact on exhaust aftertreatment cost. In this work the authors have used a 1D simulation approach to support the optimization of metallic TWC substrate for the High Power Cold Start use case. Additionally, a 3D CFD was used investigate the effect of flow rate peaks where maldistribution appears to have a major impact on the overall abatement efficiency. A complete validation of the 3D tool was made using roller bench data, measured by Aurobay on a representative production car. This step served also as an opportunity to further validate the tool, which was then used to investigate an alternative solution, where the complete insulation of the front part of the catalyst was realized. The limitation of the heat losses, along with a tailored choice of the thermal mass and properties of the substrate, allowed to guarantee the desired abatement. The result of the simulation and test campaign, lead to the optimization of the exhaust aftertreatment system, which showed increased abatement efficiency, showing how a high fidelity virtual approach can contribute to reduce the development costs.