نوع مقاله: مقاله پژوهشی
نویسندگان
1 دانشجوی سابق کارشناسی ارشد سازه های آبی؛ گروه مهندسی آبیاری و آبادانی دانشکده مهندسی کشاورزی و فناوری، پردیس کشاورزی و منابع طبیعی، دانشگاه تهران، تهران، ایران
2 دانشیار گروه مهندسی آبیاری و آبادانی دانشکده مهندسی کشاورزی و فناوری، پردیس کشاورزی و منابع طبیعی، دانشگاه تهران، تهران، ایران
چکیده
کلیدواژه‌ها
عنوان مقاله [English]
نویسندگان [English]
Flow over side weirs has been the subject of many studies. Most of these studies related to sharp crested side weirs with rectangular cross section and less attention has been given to the discharge coefficient over the broad-crested side weirs with trapezoidal cross section. In this research a comprehensive laboratory study including 187 tests has been conducted to investigate the discharge coefficient over the broad-crested trapezoidal side weir under subcritical flow regime. Since a complete analytical solution of the governing equation for a side weir is not possible due to nonlinearity and the many variables involved, in this research water surface profile along the side weir is computed by using the fourth order Runge–Kutta method. By analyzing experimental data and using dimensional analysis as well as statistical analysis, some relationships in order to estimate the discharge coefficient were proposed. It was founded that the discharge coefficient of flow depends on the Froude number, the ratio of initial depth to crest width and the side slope of the weir. The mean absolute percentage error of proposed relationship is about 4% and indicates that the numerical method is very accurate.
کلیدواژه‌ها [English]
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