Evaluation of furrow irrigation for different inflow hydrographs

Furrow irrigation is the most common type of surface irrigation. Determine the advance and recession time in the field is required the accurate measurement and this can be costly and time consuming. WinSRFR model is used for simulation furrow irrigation by zero inertia and kinematic wave engines. Using this model, advance time, reaction time, infiltration depth, runoff depth and application efficiency are calculated and compared with field data. Also, different inflow hydrograph shapes such as steady, incremental, cut back and hydrograph has been investigated in the research field in Shahid Bahonar University of Kerman. Based on the results, the kinematic wave model, Because of assuming the uniform flow through the furrow's length, has lower precision than zero inertia engine. The results showed that when an inflow hydrograph shape has smooth changes, the precision is increased. The model has the highest accuracy in calculation of advance time (1.2 percent) in steady inflow hydrograph and lowest accuracy in calculation of advance time (11.2 percent) in incremental inflow hydrograph. The highest application efficiency and the lowest runoff are accrued in cutback inflow hydrograph with 72 and 28 percent, respectively.