  Numerical simulations of vesicle suspensions are performed in two dimensions
to study their dynamical and rheological properties. An hybrid method is
adopted, which combines a mesoscopic approach for the solvent with a
curvature-elasticity model for the membrane. Shear flow is induced by two
counter-sliding parallel walls, which generate a linear flow profile. The flow
behavior is studied for various vesicle concentrations and viscosity ratios
between the internal and the external fluid. Both the intrinsic viscosity and
the thickness of depletion layers near the walls are found to increase with
increasing viscosity ratio.
