Abstract:

Rotating packed bed (RPB) has great potential in enhancing reaction and process mass transfer, but the study of its complex internal flow field is still a challenge. Understanding fluid motion is crucial for comprehending the mass transfer process. Operating the RPB in a highly sealed condition limits the ability to capture the details of the flow field inside. Computational fluid dynamics (CFD) simulations offer an effective flow field analysis method. This study proposes using a CFD model to investigate the gas-phase flow within each cavity region of the RPB. A porous media model simulates the packing region, and centrifugal rotation is incorporated into the drag calculation. Furthermore, a drag coefficient correction equation that includes the rotor speed is proposed for the first time. The experimental study covers the steady-state operational process under different rotor speeds and gas flow rates. The dry pressure drop of the RPB is obtained through iterative calculations of the drag-corrected CFD model, which serves as a key performance indicator. The average deviation between the converged pressure drop values and the experimental results is 4.71%, with a maximum deviation of 12.24%.The results of the CFD simulation are verified. Based on the validated theoretical model, further rotor performance studies incorporated a compound inverse rotor (CIR) structure with the inner rotor set to 1500 r/min. The findings indicated that the mean turbulent kinetic energy at the RPB packing increased by up to 5.77 times, thereby substantiating the potential for structural optimization in augmenting the mass transfer and treatment efficacy of the RPB. This provides a theoretical foundation for comprehensive research and development of environmental protection equipment for the RPB-enhanced chemical industry.

Key words: CFD, porous media, rotating packed bed, flow field properties

摘要：

旋转填充床（RPB）在强化反应、过程传质中存在巨大的潜力，但其内部复杂的流场研究仍然是一个挑战。研究流体运动对于探索传质过程至关重要，由于RPB运行需要处于高密封状态，所以限制了对RPB内部流场细节的捕捉，然而，计算流体力学（CFD）模拟为流场分析提供了有效途径。本研究提出了一种CFD模型用于研究RPB内部各个腔区的气相流动。采用多孔介质模型模拟填料区域，特别将离心旋转引入到阻力计算中，提出了一种结合转子转速的阻力系数修正方程。实验研究了不同转子转速和气体流量条件下的稳态运行过程，通过对阻力修正后的CFD模型进行迭代计算，得到了RPB的干压降，并作为关键性能指标，收敛压降值和实验结果的平均偏差仅为4.71%，最大偏差为12.24%，验证了CFD模拟的结果。基于验证后的理论模型，通过结合复式逆旋转子（CIR）结构，将内转子设置为1500 r/min，开展了进一步的转子性能研究。结果显示，RPB填料处的平均湍流动能最高提高到5.77倍，证实了结构优化在提升RPB传质和处理效率方面的可能性，为RPB强化化工行业环保设备的深入研发提供了理论依据。

关键词: 计算流体力学, 多孔介质, 旋转填充床, 流场特性