Abstract
Condensation of liquid water in the porous washcoat layer of exhaust gas catalysts limits their conversion efficiency during the cold-start of an internal combustion engine (ICE). The evaporation kinetics also determine the functionality of the catalyst. In this work, we study water evaporation in the washcoat layers using in-situ X-ray tomographic microscopy with high temporal and spatial resolution. A novel in-situ heating setup is developed, able to reproduce real-world conditions in terms of temperature and gas speed. It is demonstrated that with a voxel size of 0.4 μm, satisfactory data quality can be achieved with a total acquisition time for tomographic volumes of 0.5 s. Thanks to the high temporal and spatial resolution, the water evaporation in a Al2O3 washcoat layer can be described under representative conditions. We find that the time evolution of the evaporation follows an exponential-like behavior and water starts to evaporate from the macroscopic washcoat cracks.
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call