Optimization actions for irrigation by the Howell-Bunger valves

In Bahcelik Dam, irrigation and drinking water is discharged from the bottom outlet to diversion channel when the reservoir water surface elevation is between 1472 m and 1500 m. It was planned that the ow discharge would be automatically controlled by the valves depending on the water demand. In this system, the valve type is characterized by opening, closing, and regulating times of the valves for controlling system placed downstream of the main diversion channel. Howell-Bunger valves, which are cavitation and water hammer resistant, velocity limitless, and electronically controllable water control systems, were selected. In the experimental study, 4 Howell-Bunger valves each having D = 1400 mm and maximum discharge capacity 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 was found that as the reservoir elevation got higher, valve performance increased by up to 75% of valve opening. The expected discharge capacity of a valve, which worked in 100% open condition, was 8.5 m3/s; however, this value was reached with two valves that worked in 100% opening at the minimum reservoir operation level, i.e. H = 1472 m.