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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