The effect of turbulence on the particle impaction on a cylinder in a   cross flow
  Particle impaction on a cylinder in a cross flow is investigated with the use of Direct Numerical Simulations (DNS) and with a focus on the effect of turbulence on the impaction efficiency. The turbulence considered is isotropic homogeneous turbulence with varying integral scales. It is found that for particles with Stokes numbers in the boundary stopping mode there is up to 10 times more front side impaction for turbulence with a large integral scale than for a corresponding laminar flow. For decreasing integral scales the effect of the turbulence on front side particle impaction efficiency is decreasing. The back side impaction efficiency is also found to be influenced by the turbulence, but for the back side the strongest effect, and largest impaction efficiency, is found for small integral scales. 
Nikolai Hydle Rivedal, Anders Granskogen Bj{\o}rnstad and Nils Erland   L. Haugen
physics.flu-dyn