Optimizing Catalyst Substrate Technology for Gasoline vehicles in Indian Market

Emission norms are getting stringent day by day, posing new challenges such as stricter emission limits and compliance to Real Driving Emissions (RDE). Consequently, there is a pressing need to minimize emissions during cold starts, transient phases, and high exhaust flow regions. Achieving this objective requires enhancing the efficiency of after-treatment system and optimization of engine calibration. This paper discusses the approach to improve the efficiency of after-treatment system by enhancing the catalyst substrate design features such as cell density, wall thickness, and cell shape etc. The assessment was conducted to determine the emission performance advantages of substrates with higher cell densities of up to 900 cells per square inch (cpsi) and thinner web thicknesses down to 2.5 mil. This evaluation included both square and hexagonal cell shapes, comparing them to traditional substrates featuring 600 cpsi and 4.3 mil thickness. The evaluation has also included an assessment of potential risk factors, such as the durability of substrate walls resulting from reduced web thickness, and the clogging of cells due to high cell density over time as the vehicle accumulates mileage in the market. Thermal durability was also checked by running the extensive durability cycle on engine bench. This paper outlines the approach for validating the change in substrate design and discusses the significant findings from the evaluation results to determine the appropriate configuration for a given powertrain.