Abstract
Aerodynamic, volume equivalent, and mobility equivalent diameters are the cornerstones of a practical approach to the dynamics of nonspherical aerosol particles. Together, they also compose the relevant set of equivalent diameters for particle deposition and characterization by aerodynamic, electric mobility, or diffusion methods. The relationships between D AE, D VE, and D ME are discussed on the basis of a review of the dynamic shape factor concept, including the effect of slip. Emphasis is given to aggregates, especially in chainlike configurations.