  Several advances have been made in Data Assimilation techniques applied to
blood flow modeling. Typically, idealized boundary conditions, only verified in
straight parts of the vessel, are assumed. We present a general approach, based
on a Dirichlet boundary control problem, that may potentially be used in
different parts of the arterial system. The relevance of this method appears
when computational reconstructions of the 3D domains, prone to be considered
sufficiently extended, are either not possible, or desirable, due to
computational costs. Based on taking a fully unknown velocity profile as the
control, the approach uses a discretize then optimize methodology to solve the
control problem numerically. The methodology is applied to a realistic 3D
geometry representing a brain aneurysm. The results show that this DA approach
may be preferable to a pressure control strategy, and that it can significantly
improve the accuracy associated to typical solutions obtained using idealized
velocity profiles.
