optimization actions for irrigation by the howell-bunger valves

In bahçelik dam, irrigation and drinking water is discharged from the bottom outlet to diversion channel when the reservoir water surface elevation is between1472 m1500 m. it is planned that the flow discharge will be controlled by the valves automatically depending on the water demand. in this system; the valve type is characterized by opening, closing and regulating time of the valves for controlling system placed at the downstream of the main diversion channel. howellbunger valves which are cavitation and water hammer resistant, velocity limitless, electronically controllable water control systems are selected. in the experimental study, four howellbunger valves each having d=1400 mm and maximum discharge capacities q=8.5 m3/s were placed at the upstream part of the main diversion channel and tested in various valve openings to obtain optimum operating conditions for all reservoir water levels in a 1/10 scaled model. it is found that, as the reservoir elevation is getting high, valve performance increases up to 75% of valve opening. in spite of the expected discharge capacity is 8.5 m^3/s from a valve which woks in 100% open condition, this value is reached with two valves which work in 100% opening at the minimum reservoir operation level, i.e. h=1472 m.