Droplet growth by coalescence in binary fluid mixtures - art. no. 098304

The evolution of the drop-size distribution in immiscible fluid mixtures fo llowing well-specified shear histories is investigated by in situ microscop y, allowing determination of the shear-induced coalescence efficiency epsil on. At small capillary number Ca, epsilon is constant, whereas at larger va lues of Ca, epsilon decreases, in agreement with theory accounting for slig ht deformation of the drops in close approach. Coalescence causes the drop- size distribution to broaden in general, but greater deformation of the lar ger drops at high shear rates causes the drop-size distribution to remain n arrow.