The statistics of Lagrangian particles in turbulent flows is considered in
the framework of a simple vortex model. Here, the turbulent velocity field is
represented by a temporal sequence of Burgers vortices of different
circulation, strain, and orientation. Based on suitable assumptions about the
vortices' statistical properties, the statistics of the velocity increments is
derived. In particular, the origin and nature of small-scale intermittency in
this model is investigated both numerically and analytically