Comparison of Voxel-Based and Mesh-Based CFD Models for Aerosol Deposition on Complex Fibrous Filters

Aerosols represent a health risk since small droplets may enter the respiratory system and cause lung cancer, allergies, or diseases like COVID-19. In this work, an Eulerian-Lagrangian computational fluid dynamics model is used based on a voxel-based (GeoDict) and a mesh-based (StarCCM+) code. For evaluating accuracy and computational time of both models, fractional filtration efficiency and pressure drop are compared to an empirical solution for a single fiber and to experimental results for a complex 3D fibrous filter material. Simulation results of both methods are in good agreement with empirical and measurement results although the complex geometry of the fibers is captured more accurately by the unstructured mesh using the same resolution. Computing times are much faster using the voxel-based code.