عنوان مقاله [English]
In this study, a complete hydrodynamic model was used to simulate all phases of the furrow irrigation. Two sets of field data, walker and Printz were adopted for the verification of the results. The good agreement was observed among the code, SIRMOD and field data.Then, an optimization scheme was used to determine the best inflow rate and cutoff time in Merkley irrigation. The inflow rate and cutoff time were determined based on the maximum objective function. Therefore application efficiency increased from 57% to 70% and irrigation requirement efficiency increased from 81% to 95%. Then two different scenarios for optimization were determined to obtain desirable efficiencies. In the first case it was assumed that requirement irrigation efficiency and distribution uniformity was greater than 90% and the maximum values for application efficiency to be selected in this area. Application efficiency 60%, requirement efficiency 98% and distribution uniformity 90% were obtained in this scenario. In the second case, it was assumed that requirement irrigation efficiency was greater than 90%, application efficiency was greater than 70% and deep percolation to be minimum in this area. application efficiency 79%, requirement irrigation efficiency 92% and deep percolation percentage 20% was the result of this scenario. Therefore, this numerical model according to desirable efficiencies could be implemented to enhance the surface irrigation scheduling and management.