  Vesicles are micrometric soft particles whose the membrane is a
two-dimensional incompressible fluid governed by bending resistance leading to
a zoology of shapes. The dynamics of deflated vesicles in shear flow with a
bottom wall, a first minimal configuration to consider confined vesicles is
investigated using numerical simulations. Coexistence under flow of oblate
(metastable) and prolate (stable) shapes is studied in details. In particular,
we discuss the boundaries of the region of coexistence in the (v, Ca) plane
where v is the reduced volume of the vesicle and Ca the Capillary number. We
characterize the transition from oblate to prolate and analyse the divergence
of the transition time near the critical capillary number. We then analyse lift
dynamics of oblate vesicle in the weak flow regime.
