شبكه دز) E1R1 بررسي رفتار جريان غير ماندگار كانال هاي آبياري در شرايط تغييرات نياز و تعيين دستورالعمل مناسب بهره برداري (مطالعه موردي كانال

Investigation of Unsteady Flow in Irrigation Canals as a Response to Demand Variation in order to Provide Proper Operation Instructions (Case Study: E1R1 Canal of Dez Irrigation Network)

Unsteady flow in irrigation canals causes complexity in water delivery, hydraulic performance reduction, miss matching of supply and demand which are a serious challenge in irrigation canal management. One of the sources of unsteady flow in irrigation canals is implementation of delivery schedules. In this situation when the requirments of turnouts are changed, it is necessary to adjust upstream inflow, gate opening and control structures. Operation instructions should be determined according to the hydraulic behavior, hence its adverse affects on water delivery are minimized. In this research, the ICSS hydrodynamic model was used to analyze unsteady flow due to demand variation in E1RI canal of Dez irrigation network, and appropriate operation instruction was determined accordingly. For this purpose eight scenarios of increase and decrease of canal discharge to 20% due to opening or closure of turnouts were taken in to account and simulated using ICSS model. Based on the behavior of unsteady flow in irrigation canal and detemination of extra and deficite values of 6 hours water delivery to turnouts, operation instructions and proper tuning for control structures and turnouts were determined. The maximum water saved and maximum shortage decraese due to proper operation instruction were about 3962 and 7163 cubic meter respectively. Therefore, with implementation of proper operation instruction, the performance of canal was improved.