Shear-induced changes in two-dimensional foam

The effects of shear strain on a two-dimensional foam, comprising a monolay er of bubbles bridging from a soap solution to a cover glass, have been stu died. For initially disordered foam, mu(2), the second central moment of th e distribution of bubble coordination numbers, fell under strain, indicatin g ordering. The reduction in mu(2) is proportional to its initial value. Fu rther, the accompanying bubble-level changes occur in clusters, some of whi ch are large. Comparisons are drawn with recent studies. [S0031-9007(99)085 28-2].