  In many interfacial flow systems, variations of surface properties lead to
novel and interesting behaviors. In this work a three-dimensional model of flow
dynamics for multicomponent vesicles is presented. The surface composition is
modeled using a two-phase surface Cahn-Hilliard system, while the interface is
captured using a level set jet scheme. The interface is coupled to the
surrounding fluid via a variation of energy approach. Sample energies
considered include the total bending, variable surface tension energy, and
phase segregation energy. The fully coupled system for surface inhomogeneities,
and thus varying interface material properties is presented, as are the
associated numerical methods. Numerical convergence and sample results
demonstrate the validity of the model.
