FIG. 13 Profile of liquid fraction in an equilibrated foam that has undergone some collapse and drainage.

It can be seen from Eqs. (121)−(124) that for a given ε0, the occurrence of phase separation is determined entirely by the value of P. Fig. 14 shows the right-hand sides of Eqs. (121)−(124) plotted versus P for εc=0.00826. The curves AB (Eq. (124)) and BC (Eq. (123)) show the lower limit of ε0, below which foam collapse occurs, and curves DB (Eq. (122)) and BE (Eq. (121)) represent the upper limit for ε0, beyond which the continuous phase separates. Point B corresponds to L0=Lmax. At this point, there is no phase