Abstract:
In this paper, we study the feedback control problem for a mathematical model describing the motion of a nonlinear viscous fluid with infinite memory along the trajectories of the velocity field. The existence of an optimal control that gives a minimum to a given bounded and lower semicontinuous quality functional is proved. The proof uses the approximation-topological approach, the theory of regular Lagrangian flows, and the theory of topological degree for multivalued vector fields.