Settling of small particles near vortices and in turbulence (Q2744291)

From the conclusions: We have studied the behaviour of small heavy particles moving around line vortices. In particular, we have analysed some singular properties of the trajectories in order to understand the physics of the settling of particles and other related problems of interest. We have defined the key dimensionless parameters when the lift and history forces are negligible, to be the particle Froude number \(F_p\) and the dimensionless terminal velocity \(V_T\) normalized on the peak vertical velocity. By considering these parameters and the trajectories near the particle stagnation point \(X_p\), many of the effects of particle inertia for any value of the terminal velocity can be explained. We have included the effect of finite Reynolds number of the particle by using a modified (but linear) Stokes drag law.