Аннотация:We enumerate the five basic mechanisms by which any biological or manmade filter can remove particles from a fluid. These mechanisms are: (1) direct interception, (2) inertial impaction, (3) gravitational deposition, (4) motile-particle deposition, and (5) electrostatic attraction. For these mechanisms we present dimensionless indexes that indicate which measurable characteristics of the filter, the particles, and the flow affect the intensity of particle capture. By comparing the magnitudes of these indexes it is possible to determine the main mechanism a filter is using to capture particles. Awareness of these mechanisms and their interrelationships will provide insights for those investigating the efficiency of various modes of filter feeding and the mechanisms of size-selective suspension feeding.
