The Grazing Collision Angle of Aerosol Particles Colliding with Infinitely Long Circular Cylinders

Abstract

A numerical model is used to determine the grazing collision angle of aerosol particles of a few micrometers in size colliding with infinitely long cylinders of radii of 15 and 30 μm. Collision mechanisms considered are interception and inertial impaction. Reynolds numbers ranging from 1 to 5 are investigated. The grazing angle is found to increase with increasing collision efficiency owing to the combined effect of inertial impaction and interception. An empirical fit is given to relate this angle with the collision efficiency. The size differentiation at different angles and the implications to aerosol filtration are discussed.