Effects of regenerative mechanical vibration on the mechanical integrity of ceramic diesel particulate filters

Abstract

Abstract:In this study, the effects of mechanical vibration on the mechanical properties of ceramic diesel particulate filters (DPFs) were investigated. The goal is to determine how the mechanical vibration used in the regenerative ash cleaning process for these filters affects their mechanical integrity during subsequent reuse. Both virgin and vibrated DPF samples were subjected to compressive and 3-point flexural loading at three different loading rates along axial and tangential directions. Statistical analysis was conducted to determine the significance of variation in the compressive and flexural strengths of the DPFs as a result of exposure to mechanical vibration. The results show that there is no statistically significant difference in both compressive and flexural strengths of the virgin DPFs and the DPFs subjected to the same level of mechanical vibration typically used in ash cleaning of DPFs. When the intensity of vibration was doubled, the drop in compressive strength became statistically significant, but less than 10% under axial loading. However, no drop in flexural strength was observed for DPFs subjected to this high intensity of mechanical vibration. The safe threshold for mechanical vibration of ceramic filters is considered to be much higher than that currently used in vibration-based ash cleaning process.

Enhanced sound absorption properties of porous ceramics modified by graphene oxide films

“…To address this issue, researchers have created several sound‐absorbing structures such as a Helmholtz cavity and a variety of sound‐absorbing materials such as polyurethane foam. Porous materials with large microstructure air–solid interfacial areas generally have wide absorption frequency ranges, excellent sound absorption performance, and other properties desired in several engineering applications 6–13 . However, porous materials with thickness >30 mm have poor absorption coefficients below 500 Hz, usually <0.4 14–24 because sound energy dissipation is a quadratic function of frequency in the sound absorption mechanism of porous materials.…”