Nonlinear Diffusive Wave Modeling and Identification of Open Channels

This paper deals with the identification of an irrigation system in the presence of not completely known withdrawals. The modeling approach is based on a time-implicit finite-dimensional model of simplified equations governing open-channel hydraulics. The diffusive wave model is used with a parameterization based on large rectangular geometry and solved using the Muskingum-Cunge method. A two-stage iterative method is proposed to identify the dynamic parameters and the withdrawal parameters. In the first stage, only the parameters governing the withdrawals are estimated, and in the second stage, the estimated withdrawals are used to estimate the parameters of the dynamics. The simulation studies performed on simulated and real data show the effectiveness of the identification method.