Fibrous filters are widely used for air cleaning, gas purification, and aerosol sampling. A fibrous filter can be viewed as an assembly of fibers randomly oriented in planes perpendicular to the direction of flow. Particles suspended in the gas are removed by their collision and attachment to the surface of fibers or deposited particles.

While fibrous structure is not simple, it is generally understood how to model particle collection in such a structure. However, with particle deposition on fibers, filter structure becomes much more complicated, and theoretical modeling of the altered structure on particle collection could be a much more difficult task, which is the focus of this talk.