Numerical simulation of breakup of a viscous drop in simple shear flow through a volume-of-fluid method

A spherical drop, placed in a second liquid of the same density, is subject ed to shearing between parallel plates. The subsequent flow is investigated numerically with a volume-of-fluid (VOF) method. The scheme incorporates a semi-implicit Stokes solver to enable computations at low Reynolds number. Our simulations compare well with previous theoretical, numerical, and exp erimental results. For capillary numbers greater than the critical value, t he drop deforms to a dumbbell shape and daughter drops detach via an end-pi nching mechanism. The number of daughter drops increases with the capillary number. The breakup can also be initiated by increasing the Reynolds numbe r. (C) 2000 American Institute of Physics. [S1070-6631(00)02002-X].