Critical conditions for inertial particle deposition from a gas flow near a retardation point

The critical conditions are considered for inertial deposition of particles from a laminar planar gas flow in the region of a retardation point. An exact numerical calculation on the paths of individual particles is used along with an approximate analytic solution to examine the effects of the boundary layer on the critical Stokes number. A study is made of the effects of the Sufman upthrust acting on a particle in the boundary layer as regards the critical deposition conditions and the redistribution of small particles over the boundary layer.