Mass transfer and liquid hold-up in structured packing geometry are investigated using the volume of fluid method. Numerical simulations of two-dimensional co-current gas–liquid flow on structured packing with interfacial mass transfer are performed. The volume of fluid method is used to capture the gas–liquid interface motion. The mass transfer is computed by solving the concentration equation with an adapted modeling of the solubility (Haroun et al., 2010b). The liquid hold-up and the mass transfer are studied as function of liquid flow rate and structured packing geometry. Results show how the liquid flow rate and the complex geometry affect the liquid film flow topology and the interfacial mass transfer. For a specified packing geometry, it is demonstrated that for low liquid flow rate, the liquid film remains uniform and follow closely the profile of the structured wall. For uniform liquid film flow along packing wall, it is found that the liquid hold-up is in good agreement with the model proposed by Billet and Schultes (1999) and Raynal and Royon-Lebeaud (2007). When increasing the liquid flow rate, the liquid film does not follow the shape of the structured wall anymore, a static hold- up (recirculation zone) form in the cavities and grows as the Reynolds number increases until covering most of the packing cavities. The present work gives the liquid hold-up evolution for each liquid film flow regime according to the Reynolds number and the dimensionless amplitude of the corrugation. Concerning the liquid side mass transfer, it is found that the liquid side mass transfer is well predicted by the Higbie (1935) theory provided that adequate velocity and length scales are considered for exposure time determination. The exposure time of fluid element at the interface corresponds to the ratio between the curvilinear distance between two periodic corrugation contact point and the interface velocity. An exposure time model is proposed taking into the account physical and geometric parameters.
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机译：使用流体体积法研究了规整填料几何形状中的传质和液体滞留率。在带有界面传质的规整填料上进行二维并流气液流动的数值模拟。流体体积法用于捕获气液界面运动。传质是通过对浓度方程式进行溶解度调整后算出的（Haroun等，2010b）。研究了液体滞留量和传质与液体流速和规整填料几何形状的关系。结果表明，液体流速和复杂的几何形状如何影响液膜流动拓扑和界面传质。对于特定的填充几何形状，已证明对于低液体流速，液膜保持均匀并紧贴结构壁的轮廓。对于均匀的液膜沿填料壁流动，发现液体滞留率与Billet and Schultes（1999）和Raynal and Royon-Lebeaud（2007）提出的模型非常吻合。当增加液体流速时，液膜不再遵循结构化壁的形状，在腔中形成静态滞留（再循环区），并随着雷诺数的增加而增长，直到覆盖大部分填充腔。本工作根据雷诺数和波纹的无量纲振幅给出了每种液膜流动状态下的持液率演变。关于液体侧传质，发现Higbie（1935）理论很好地预测了液体侧传质，前提是要考虑足够的速度和长度尺度来确定曝光时间。流体元素在界面处的暴露时间对应于两个周期性波纹接触点之间的曲线距离与界面速度之比。考虑到物理和几何参数，提出了曝光时间模型。
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