Boundary integral simulation of the motion of highly deformable drops in a viscous flow with spontaneous Marangoni effect

We report on three dimensional boundary-integral code and on simulations of the motion of highly deformable drops in the presence of Marangoni effect. Our focus is on the case when the concentration gradients that cause the tangential stresses on the interfaces are not externally imposed but are induced spontaneously induced by the interfacial transfer of surfactants (spontaneous Marangoni effect). When drops move in viscous fluid under intensive external forcing, large deformations, cusps formation and breakup of the drops are typical. The results of the simulation of an initially deformed single drop in gravity field and in linear flow are presented. Our simulations show that even weak Marangoni effect may drastically change the deformation pattern in critical situations.