Many investigations find that mass transfer efficiency decreases dramatically with increasing viscosity, which poses challenges to the industrial processes with the highly viscous mixture. We use liquid films on a vertical plate with windows to address this problem. The hybrid twin-liquid films combine the motility of free-falling films with the stability of wall-bounded films. In this study, the film thickness distributions are measured experimentally, and the detailed hydrodynamics and mass transfer process are studied with numerical simulations. The results reveal the hydrodynamic and mass transfer behaviors of highly viscous twin-liquid films. Due to gravity acceleration inside the window, the maximum velocity of liquid films increases by 2.5–16 times, and the maximum local mass transfer rate increases by 2–6.5 times in our simulations. We conclude that compared with conventional methods, open windows significantly enhance mass transfer in viscous liquid films without additional cost.

许多研究发现，随着粘度的增加，传质效率急剧下降，这给高粘度混合物的工业生产带来了挑战。我们在带有窗口的垂直板上使用液膜来解决此问题。混合双液膜将自由降落膜的运动性与壁边界膜的稳定性结合在一起。在这项研究中，通过实验测量膜的厚度分布，并通过数值模拟研究详细的流体动力学和传质过程。结果揭示了高粘性双液膜的流体动力学和传质行为。由于窗口内的重力加速度，在我们的模拟中，液膜的最大速度增加了2.5–16倍，最大局部传质速率增加了2–6.5倍。