نوع مقاله : پژوهشی
نویسندگان
دانشکده ی مهندسی عمران- دانشگاه فردوسی مشهد
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Weirs are widely used in agricultural and hydraulic engineering for measuring and regulating flow. Various shapes of weirs give rise to their special characteristics. One of the Weirs problems in irrigation system is the change of hydraulic characteristics when upstream of the weirs is filled by sediments. This study introduces a novel sharp-crested weir design with a cosine weir and investigates physical models of cosine sharp-crested weirs of different widths. The analysis aims to establish the head discharge relationship and inspect velocity distribution and the hydrodynamic characteristics of flow in the vicinity of the weir plate. The hydraulic behavior of the cosine weirs is compared with that of rectangular sharp-crested weirs. The results showed that the turbulence intensity in the vicinity of the cosine weirs was stronger than that in rectangular weirs. In addition, turbulence intensity, r, is sidewall cosine weirs more than the rectangular weirs. Therefore, this type of weir could provide the sediment transport at the upstream weirs. Result showed that the increasing water head at the upstream with $y/P>0.78$ confection discharge was diminished (y is the height of water on crest weir, and P is the height of weirs from bottom to crest). In addition, with $y/P
کلیدواژهها [English]
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