Closed-End Border Irrigation Design with WinSRFR Simulation Model Using Particle Swarm Optimization Techniquee

Estimating the parameters of infiltration equation and Manning’s roughness coefficient are essential for the optimal design and evaluation of surface irrigation systems. The present study was carried out to calibrate these coefficients for a closed-end border irrigation system with four series of field information. In this regard, the hydraulic surface water flow is simulated using zero-inertia model by WinSRFR simulation model that linked to the particle swarm optimization algorithm for repetitive calculations. The objective function of the optimization problem was the minimization of the difference between the calculated and measured times of advance and recession phases, and four coefficients of the modified Kostiakov equation and Manning’s roughness coefficient were considered as decision variables. The sensitivity analysis of the developed model showed that the coefficient b of infiltration equation in the recession phase and the Manning’s roughness coefficient in the advance phase have the most errors in the predicted results. The results showed that based on the optimized parameters in the model, the values of root mean square error, RMSE, were obtained between 3.77 to 12.86 minutes and the coefficients of residual mass were varied between -0.099 and 0.003 to predict the advance and recession times in the four experimental irrigations. Based on results, with optimization of WinSRFR model, there is accessibility to achieve in application efficiency and distribution uniformity about 86 and 84 percent, respectively (with adequacy about 100 percent) by flow variable (inflow rate and cutoff time).