A note on stages of evolution in a 2D froth

The scaling properties of 2D froth have been extensively investigated via numerical simulations, theory and experiment. The evolutionary process as a whole, however, consists of two regions involving several distinct stages, which are characterized by the froth structure. In particular, transient behaviour which reflects initial levels of froth disorder can be varied both in its nature and duration. The final stage of froth evolution is associated with a few remaining bubbles, which change relatively slowly, unlike the many, frequent changes originally associated with transience. Thus, late configurations do not affect achievement of scaling, but influence the rate at which it is attained. Recent studies of ordered 2D froths with single/multiple defects provide some examples for length of transition period, which appears to be related to concentration of defects, and highly ordered systems with few defects exhibit an anomalous approach to the scaling state. Details are briefly discussed.