Explosive growth of inhomogeneities in the distribution of droplets in a   turbulent air
  We study how the spatial distribution of inertial particles evolves with time in a random flow. We describe an explosive appearance of caustics and show how they influence an exponential growth of clusters due to smooth parts of the flow, leading in particular to an exponential growth of the average distance between particles. 
S.A. Derevyanko, G. Falkovich, K. Turitsyn, and S. Turitsyn