Piano key (PK) weirs are used in a variety of flow control structure applications, including spillway crests and open channel diversion structures. However, to the best authors’ knowledge, structure-specific design guidance for scour mitigation is still needed. To fill this gap systematic experimental campaign was conducted by testing different configurations horizontal aprons with cutoff wall....

Abstract Energy dissipation across the weir and dam structures is a vital economic technical solution for designing downstream morphology of any hydraulic system. Accurately estimating energy over system using traditional empirical formulas tedious challenging. Consequently, employing new precise techniques still in high demand crucial. In this study, authors developed an model residual type-A ...

A modified piano key weir with a rounded nose and parapet wall (MPKW) can improve the discharge capacity significantly compared to standard weir. However, optimum of inlet/outlet width ratio (Wi/Wo) on efficiency MPKW is still not investigated numerically. The present work utilized numerical modeling investigate analyze effects ratios hydraulic characteristics MPKW. To validate model experiment...

Abstract Energy dissipation is one of the important issues in piano key weirs (PKWs). Excessive energy at weir's toe can cause scouring. In previous studies, arced (APKWs) has not been investigated. this experimental study, effect weir height as well and arrangement baffles located on outlet slope amount dissipated were examined trapezoidal (TPKWs) APKWs. Experiments performed models with two t...

This investigation deals with the mechanics of movement singular quartz gravel and coarse sand riverbed particles upstream over inlet key three Type A piano weir (PKW) models, which were recorded a high-speed camera. Acoustic Doppler velocimeter was used to obtain bed shear stress. The sediment threshold regime compared previous investigations found be within ranges. Generally, particle deceler...

Free crest spillways are hydraulically efficient and safe in operation. Since their discharge capacity is directly proportional to the crest length several types have been developed with the purpose to increase the length of the latter. Among these types traditional labyrinth weir spillways have been studied and used for a long time. Their hydraulic performance and the effect of the involved ge...