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Elva Ortega-Torres

Publications and source records attributed to Elva Ortega-Torres.

5 recordsLinked to original sources

An optimal control problem for the Navier-Stokes-$α$ system

In this paper we study a distributed optimal control problem for a three-dimensional Navier-Stokes-$α$ model. We prove the solvability of the optimal control problem, and derive first-order optimality conditions by using a Lagrange multipliers Theorem. Finally, considering a velocity tracking control problem for the three-dimensional Navier-Stokes-$α$ model, we analyze the relation of its optimality system to the corresponding one associated to the Navier-Stokes model by proving a convergence theorem, which establishes that, as the length scale $α$ goes to zero, the optimality system of the three-dimensional Navier-Stokes-$α$ model converges to the optimality system associated with the velocity tracking control problem of the Navier-Stokes equations.

math.OC

An Optimal Control Problem for the Steady Nonhomogeneous Asymmetric Fluids

We study an optimal boundary control problem for the two-dimensional stationary micropolar fluids system with variable density. We control the system by considering boundary controls, for the velocity vector and angular velocity of rotation of particles, on parts of the boundary of the flow domain. On the remaining part of the boundary, we consider mixed boundary conditions for the vector velocity (Dirichlet and Navier conditions) and Dirichlet boundary conditions for the angular velocity. We analyze the existence of a weak solution obtaining the fluid density as a scalar function of the stream function. We prove the existence of an optimal solution and, by using the Lagrange multipliers theorem, we state first-order optimality conditions. We also derive, through a penalty method, some optimality conditions satisfied by the optimal controls.

math.OC