Discharge Calculation of Side Weirs with Several Weir Fields Considering the Undisturbed Normal Flow Depth in the Channel

Discharge behavior at side weirs is significantly influenced by the water surface profile along weir crest. In past century, different approaches were developed to describe this and associated discharge coefficients. However, application of these methods practical problems poses a particular challenge, as complex three-dimensional funnel formed due reduction, leading significant uncertainties in determining relevant flow depth. For reason, new approach for determination coefficient was that refers undisturbed normal depth main channel. Based on comprehensive parametric study utilizing 3D-numerical simulations, influence channel characteristics analyzed. A revised formula estimating with multiple fields derived using regression analyses. Validation numerical simulations carried out applying physical scale model, showing good agreement between results.