A GENERAL INTERACTION POTENTIAL MODEL BETWEEN PLATEAU BORDERS TO DETERMINE THE STRAIN-RATE OF LIQUID FOAMS

In this paper we present a general model based on interactions between plateau borders to determine the strain rate of the two dimensional l iquid foam. It is found that a defect length is responsible for the st ress concentration and thus the flow of cells through the foam. The fl ow is local. The underlying assumption is that the area of the unit ce ll which undergoes a T1 process remains invariant. This leads to the p ersistant of the defect length which is responsible for the flow. It i s found that the strain rate is given as gamma = c rho b nu(l) where c is a constant, rho is the number per unit length of the persistant le ngth, b is the displacement of the cells and nu(l), is the rate of con traction of the persistent length.