Modeling, Simulation and Control of Irrigation Canal Networks

Irrigation canal networks play a pivotal role in satisfying the water demands of farmlands around the world. In a time of global warming, automatic irrigation systems are crucial in order to minimize water losses caused by human error and complex dynamics. This work serves as a holistic approach towards the problem of modeling, simulating and controlling the fluid dynamics of irrigation canal networks. The PDEs describing the flow dynamics are briefly illustrated, along with the dynamics introduced by the canal hydraulic structures. The PDEs are simulated using a 2nd order Finite Volume Scheme. The scheme utilizes an HLL Riemann Solver for the spatial discretization and an SSPRK2 time integrator for the temporal discretization. The full flow dynamics are approximated using various control-oriented lumped-parameter LTI models derived from literature. The LTI models are compared against the full system dynamics in the time and frequency domains. Subsequently, a centralized MPC master-slave controller is utilized for stabilizing the water levels of the irrigation canal network under changes in the flow regime. The proposed controller is coupled with the devised fluid simulator. Finally, the response of the irrigation canal control system is exhibited in a simulated version of the Corning Canal in California, USA, which serves as Test Case 2 according to the benchmarks set by ASCE for developing canal control algorithms.