Coarsening of monodisperse wet microfoams

We report experiments on the aging of monodisperse wet microfoams. We use the flow focusing technique to produce perfectly monodisperse microbubbles from 50 to 80 mum in diameter. This results in a foam of spherical bubbles of the same size ordered in random ordered lattices like "crystal grains" above the foam/liquid interface. We observe two different behaviors while the foam drains without any interference. At early times, the foam bubble size is almost constant from 10 to 20 min depending on the initial diameter of the bubbles. For longer times, the foam reaches a scaling state where the bubbles mean diameter growth agrees with the theoretical prediction t(1/3). (C) 2004 American Institute of Physics.