Free-surface aeration in dam break waves: an experimental study

New air–water flow experiments were conducted in the leading edge of dam break waves. The data highlighted the chaotic nature of the surge and provided new insights in the distributions of void fraction, velocity and air/water chord sizes. The results demonstrated a highly aerated surge front with a developing turbulent boundary layer. At the leading edge, observed mean air contents exceeded 40 to 50%, implying that sediment motion would be predominantly bed-load.