DISCHAGE COEFFICIENT OF OBLIQUE SIDE WEIRS

• Published in: PROCEEDINGS OF HYDRAULIC ENGINEERING Vol. 44; pp. 545 - 550
• Main Authors: MORIYAMA, Hirotaka, KITA, Yoshinori, URA, Masaru, AKIYAMA, Juichiro
• Format: Journal Article
• Language: English
• Published: Japan Society of Civil Engineers 2000
• Subjects: discharge coefficient; oblique side-weir; side-weir
• ISSN: 0916-7374; 1884-9172
• DOI: 10.2208/prohe.44.545

An investigation of side-weirs, used as a diversion structures in rivers and canals, is presented. Most commonly, the side-weirs are aligned parallel to the direction of flow in the parent canal, giving an off-take angle, θ of 90 degrees. However, this study investigates performance of oblique side, weirs, that off-takes at an angle less than 90 degrees. Discharge coefficients for oblique weirs are obtained theoretically and experimentally as functions of off-take angle, θ, Fronde number in the parent channel and weir geometry. It is found that a high value of discharge coefficient can be maintained when θ lies between 60and 80 degrees. A side weir with θ equal to 70 degrees is selected for tiuther study with improved frontal apron and approach wall. It is concluded that the value of discharge coefficient can he further increased for a wide range of high Fronde numbers through these improvements.