Formation of Chimneys in Mushy Layers: Experiment and Simulation
  In this fluid dyanmics video, we show experimental images and simulations of chimney formation in mushy layers. A directional solidification apparatus was used to freeze 25 wt % aqueous ammonium chloride solutions at controlled rates in a narrow Hele-Shaw cell (1mm gap). The convective motion is imaged with schlieren. We demonstrate the ability to numerically simulate mushy layer growth for direct comparison with experiments. 
Anthony M. Anderson, Richard F. Katz, and Grae Worster
physics.flu-dyn