Backwater effects of Jambor weir sill

Abstract

Compared with traditional weirs, Jambor weirs have the advantage that they reduce afflux due to their hydraulically-optimized shape. Hence, for identical discharge capacity, the height of the gate and thus the cost are reduced significantly. Although Jambor weir sills have been used in a combination with movable weirs for decades, the relationship between sill height, headwater and tailwater conditions and the resulting discharge has so far not been investigated systematically. Based on extensive tests in a hydraulic flume, an empirical equation and a dimensionless design chart were developed to estimate the backwater effect in the design phase to achieve the highest possible weir sill with an optimum hydraulic performance.

Keywords:

• Backwater effect
• broad-crested weir
• drag coefficient
• submerged flow
• weir sill