Lattice Boltzmann simulations of three-dimensional single droplet deformation and breakup under simple shear flow

We present three-dimensional numerical simulations of the classical Taylor experiment on droplet deformation within a shear flow. We have used the pro mising lattice Boltzmann method numerical scheme to simulate single droplet deformation and breakup under simple shear how. We first compute the defor mation of the droplet, and find excellent agreement with the theoretical pr ediction. We have used the same method to simulate the shear and breakup fo r larger values of the sheer rate. We find that the lattice Boltzmann metho d used in conjunction with the interface force model of Shan and Chen [Phys . Rev. E 47, 1815 (1993); 49, 2941 (1994)] results in an excellent treatmen t of the entire process from small deformation to breakup into multiple dro plets. Our results could be extended to study the rheology of dispersed dro plets and the dynamics of droplet breakup and coalescence in shear flow. [S 1063-651X(99)13603-1].