نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه آب دانشکده مهندسی عمران دانشگاه زنجان
2 کارشناسی ارشد عمران- سازه های هیدرولیکی
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
Weirs located on rivers massively used to regulate the flow of water, facilitate flow diversion for acrigaltur porpuses. Given that the weirs site is often restricted in width, weirs with different shapes have been dveloped to increase weir length and discharge capacity.Accurate estimation of the maximum possible depth of scour at weirs is important in decision-making for the safe depth of burial of footings. Labyrinth weirs located on the rivers are often exposed to Flood, therefore one of the principal challenges of their use of them is scouring around them. In this study, the influence of water head ratio and sidewall angle was investigated on flow pattern at first and then scour mechanism. Then considering the close relationship between flow pattern and scour phenomenon, We studied the parameters effecting the scour at the upstream weir by focusing on the pattern flow. Observations showed that by changing the water head ratio, it is possible to have four different regimes and Each of these regimes has a different effect on the scour mechanism and maximum depth scour location. As the water head ratio is increased, in addition to the significant expansion of the scour hole dimensions, the location of hole formation is displaced from the vicinity Weir’s walls to the center of the cycle. In addition to the water head ratio, the sidewall angle also has a meaningful effect on the mechanism and amount of scouring on the weir. As the sidewall angle is increased, the amount of scouring is significantly decreased.
کلیدواژهها [English]
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