Less pressure loss with extra packing — The counterintuitive behavior of rotating packed beds

Abstract

The Rotating Packed Bed (RPB), as a process intensification unit in heat and mass transfer of multiphase processes, has been gaining growing attention in recent years as reflected in the numerous investigations of the device. However, many questions remain unanswered regarding the fluid dynamics in RPBs, including the counterintuitive behavior of higher dry pressure drop in operations with empty rotor compared to operations with packed rotor. To address this issue, we employ numerical methods to acquire a detailed description of the fluid flow inside the device. The metal foam as the packing material is resolved through reconstruction techniques found in the literature. The simulation results reveal that the absence of packing, due to conservation of angular momentum, induces higher local velocities and therefore higher pressure loss. Further, we derive fundamental mechanism of the pressure loss inside the RPB from the local data that can potentially enhance existing correlations.