Pore-scale filtration simulations require high spatio-temporal resolutions and significant computational effort, hence, keeping the domain size to a minimum is desirable. Previous studies have considered domains based on Brinkman length, or are limited by computing power, and little information is available for conditions involving high fluid saturation – typical of steady state mist filtration. In this study, simulations are performed to characterize the effect of domain size on pressure drop, residual saturation, liquid film thickness and interfacial area concentration, using virtual nonwoven and foam filters with similar micro-structural properties. Further, experiments using micro-CT are performed to validate the present computational simulations. It is found that two phase flow through filters are more sensitive to local geometric variations or mesh resolution in the porous media than single phase flow. Statistical uncertainties in the steady state quantities of less than $\pm$10% can be expected to cope with the increase in computing power required for practical mesh sizes. A computational domain size of about 50–100 $\times d$ (where d is the strut or fibre diameter) was found to be required for CFD for the operating conditions considered.

孔径过滤模拟需要较高的时空分辨率和大量的计算工作，因此，希望将域大小保持为最小。以前的研究已经考虑了基于Brinkman长度的域，或者受计​​算能力的限制，并且对于涉及高流体饱和度的条件（稳态雾过滤的典型特征），几乎没有可用的信息。在这项研究中，使用虚拟的非织造布和具有类似微结构特性的泡沫过滤器，进行了仿真，以表征畴尺寸对压降，残余饱和度，液膜厚度和界面面积浓度的影响。此外，执行使用微型CT的实验以验证当前的计算仿真。已经发现，与单相流相比，流过过滤器的两相流对多孔介质中的局部几何变化或网格分辨率更敏感。稳态量的统计不确定性小于$\pm$可以预期有10％的像素可以应付实际网格尺寸所需的计算能力的提高。计算域大小约为50–100$\times d$对于所考虑的操作条件，发现CFD需要使用d（其中d是支撑杆或纤维直径）。