JWSS - Journal of Water and Soil Science

In this study, the WEAP model was used for the simulation and the Gravitational Search Algorithm (GSA) was applied as the optimization model. Due to the necessity of multiple simulations in the optimization process to achieve the optimal solution, the linkage of simulation and optimization models was done in the MATLAB software environment. To evaluate the performance, hedging policies achieved in the base period were investigated for the near future period under climate change. The results showed the poor state of aquifers under the baseline scenario; also, the continuation of the current management caused the Zayandehrood river basin to experience significant problems. So management of water resources using conjunctive hedging policies could improve the situation. The use of conjunctive hedging rules showed 11 percent increase in the group sustainability index for demands, in comparison with the baseline scenario. Also, according to the group sustainability index for the resources, applying the conjunctive hedging policies could increase the sustainability of surface water and groundwater resources as much as 5.2 and 6 percent, respectively, relative to the baseline scenario. The results also indicated the better performance of conjunctive hedging policies in comparison to the baseline scenario policies.

Lopac gates, with the benefits of easy installation, automation and the ability to pass sediments and floating objects, are among the new structures considered for water level regulation and flow control in the irrigation canals. Converting the shape of the gate from a rectangular one to an elliptical one allows the flow rate to be increased by the same water level. In the present study, the effect of the sudden transition on the discharge and energy dissipation of the elliptical-lopac gate (ELG) in the submerged flow conditions was evaluated in the laboratory. The results showed that the dimensionless discharge and energy dissipation of the ELG with sudden transition to channel width conditions was decreased by 28 to 86% and increased by 11 to 35%, respectively. Finally, the statistical equations were presented to estimate the dimensionless discharge and energy dissipation of ELG by sudden transition under submerged flow conditions with a maximum error of 16%.