MAXIMUM STABLE DROP DIAMETER IN STIRRED DISPERSIONS

Transient drop-size distributions of stirred dispersions undergoing br eakage were experimentally measured at long stirring times. The result s show that drops continue to break the entire duration of the experim ent (at least up to 10 h) and force a reevaluation of the widely held concept of a maximum stable drop diameter, d(max). Transient distribut ions show the existence of self-similarity which is the same as that o bserved in transient distributions obtained at short times (up to simi lar to 1 h, Sathyagal et al., 1995b) indicating that the nature of bre akage does not change with time. The existence of similarity at long s tirring rimes can be used to obtain goon estimates of breakage rates o f small drops by an inverse problem procedure.