Hydraulic Characteristics of Flow over Circular Crested Weirs
Keywords:
Circular weir, Discharge coefficient, crest shapeAbstract
In this investigation nine models of circular crested weir were constructed and tested during an experimental study. Crest radius( r) of the weir was varied three times; 2.5 cm, 3.1cm and 3.75cm. For every crest radius the weir height (p) was varied three times; 15cm, 20cm and 25cm. The result was showed that the discharge coefficient (Cd) affected by two factors; head above the weir to the crest height (h/p) and head above the weir to the crest radius (h/r). It was observed that coefficient of discharge (Cd) increased with increasing (h/p) for the similar height of weir and for definite value for the ratio h/p the (Cd) value increased with increasing the crest height (p). Also it was found that coefficient of discharge (Cd) increased with increasing (h/r) for the similar crest radius and for definite value for the ratio (h/r), the (Cd) value increased with increasing the crest radius (r). A simple power experiential expression was found for the variation of (Cd) with (h/p) and (h/r) with high correlation coefficient.
References
Benyamin Naghavi et al. (2011), "An experimental and numerical study on hydraulic characteristics and theoretical equations of circular weirs”, Can. J. Civ. Eng., vol. 38, pp. 1327–1334 .
British Standards Institution (1965),"Method of Measurement of Liquid Flow in Open Channels", part 4A, Bs3680, BsI, London, England.
Budapest and Hungary ‘aspects in designing aquaculture system’ , Research centre for water resources development.
Chanson H. and Montes J.S. (1998),"Over flow characteristics of circular weir: Effects of Inflow conditions", ASCE, Journal of Irrigation and Drainage Engineering, Vol.124, No.3, pp.152-162.
Emad Abdul_Gabbar Al Babely et al (2011), "Overflow Characteristic of Cylindrical Shape Crest Weirs Over Horizontal Bed",Tikrit Journal of Engineering sciences, Vol.18 , No.4, pp.29-39.
Hayawi H.A. and Al-Moula S.J.(2006),"coefficient of discharge for the Normal and Oblique weirs with semi-circular crest", AL Rafidain Engineering,Vol.14, No.2, pp.33-47.
Noori B.M.A. and Chilmeran T.A.H. (2005),"characteristics of flow over normal and oblique weirs with semi circular crests", Journal of AL Rafidain engineering, Vol.13, No.1, pp.49-61.
Ramamurthy A.S., and Ngoc - Diep Vo (1993),"characteristics of circular-Crested weir", ASCE, Journal of hydraulic engineering, Vol.119, No.9, pp.1055-1062.
Thabet M. Abdul-latif et al.(2010),” Calibrating the Discharge Coefficient of Semicircular Crested Weir”,Eng.₰ Tech. Journal, Vol.28, No.24.
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