Optimal control of sedimentation in navigation channels

Many hydraulic engineering projects concern the control of sedimentation. F or some large engineering projects, such as construction of a navigation ch annel over many kilometers in a shallow estuary, comprehensive control of s edimentation is extremely costly. An optimal-control approach is presented. It determines optimal locations and scheduling of dredging to minimize tot al cost and to obtain a channel where water depths are not less than specif ied values. The optimal-control problem is formulated and a method is devel oped. The optimization problem is solved by the conjugate gradient method, and the gradient of the cost function is calculated by solving the adjoint problem. A simulation study is conducted using a 2D numerical model to demo nstrate the method. The significance of the adjoint problem is also illustr ated in sensitivity analysis experiments.