This study experimentally and numerically investigates the de-NOx performance of monolithic catalyst substrates with various cell densities. Lab-scale experiments employing catalyst-coated metallic monoliths were conducted to measure conversion performance under steady-state and isothermal conditions. Pressure drop through the substrate was predicted by numerical simulations. This study identifies a counterbalancing effect resulting in non-monotonic conversion behavior as cell density increases, particularly at low temperatures. The findings of this study suggest that cell density plays a crucial role in optimizing de-NOx performance, especially for large-scale devices such as marine after-treatment systems. Furthermore, a correlation for predicting pressure drop as a function of the cell density was established based on numerical simulations. Using both experiments and computations, this study provides the underpinning knowledge with a view to designing a monolithic catalyst for practical applications.
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