Hydrodynamics of Diesel Particulate Filters

Renewed interest in utilizing wall-flow Diesel Particulate Filters (DPF) in emission control systems necessitates gaining deeper engineering insight into their performance. Even though most key performance characteristics of a DPF such as pressure drop, regeneration, and light-off are highly driven by the flow motion through it, there appears to exist only minor and scattered information on the fundamental aspects of filter hydrodynamics. In this correspondence, many DPF hydrodynamic and particulate transport features such as frictional losses, inlet, exit, Darcy and Forchheimer pressure drop contributions, role of flow temperature and particulate loading and their individual pressure drop contributions are discussed. Discussions are also provided on different flow velocity components in a filter channel, their individual contributions to the filter pressure drop, and their laminar and turbulent flow regimes. Recent findings reported in the literature are also reviewed.