Structure from Motion for the Creation of Realistic 3D Models of ISO Fine Test Dust

Abstract

ISO Fine Arizona test dust is a typical surrogate contaminant for air filtration. Donaldson differential pressure simulations model dust particles as spheres. Filter performance is defined by terminal differential pressure and the rate at which it is achieved. Use of more realistic geometries is expected to improve simulation predictivity. Common characterization methods are insufficient to describe particle morphology in three dimensions. The present work lays out an accessible workflow using Structure from Motion, a photogrammetric technique, to convert a series of overlapping two-dimensional SEM micrographs into a three-dimensional dust model. The 3D workflow is informed by an analysis of 2D shape performed on thousands of ISO Fine particles. Packed bed experiments comparing realistic 3D-printed dust particles and volume-equivalent spheres demonstrate differentiated performance at a scale that is relevant to the filtration industry.