Abstract
The problem of controllability for optimal control problems, optimization of systems with distributed parameters in partial derivatives is considered. The concept of controllability as correctness according to A. N. Tikhonov for solving optimization problems is introduced. A theorem with controllability conditions for direct solution (direct minimization of the objective functional) of optimization problems by extremal algorithms is given. A test example of numerical solution of the optimization problem for a nonlinear hyperbolic system describing non-stationary water flow in an open channel is considered. Controllability analysis is demonstrated, which ensures correctness of the solution of the problem and high accuracy of optimization of the distributed friction coefficient in the flow equations.