Shell analysis and effective disorder in a 2D froth

The static and evolutionary properties of two-dimensional cellular structur es, or froths, are discussed in the light of recent work on structuring of the froth into concentric shells. OF interest is the dual role of a topolog ical dislocation ("defect") in an otherwise uniform froth, considered both as a source of disorder and also as a source generating a shell-structured froth. We present simulations on an initially uniform hexagonal Froth. A de fect is introduced by forcing either a T1 or T2 process in the stable struc ture, after which the Froth is allowed to evolve according to von Neumann's law. In the first case; topological inclusions are found in the first few layers early in the evolution. In the second case, no inclusions appear ove r the entire evolutionary period. The growing disorder (as measured by the second moment of the side distribution, mu(2)) is isotropic. For the specia l case of a T2-formed Froth in a uniform network, the SSI structure is reta ined with mu(2)not equal 0 only for the zeroth, first, and second layers. T he ratio between topological perimeter and radius of the shells is close to 6, the value for a hexagonal froth.