Drag on vertical sill of forced jump

Abstract

As a basis for designing a forced-hydraulic-jump-type stilling basin, the pressure magnitude on the upstream and downstream faces of a continuous-vertical sill has been investigated experimentally, and the nature of the pressure distribution on the faces of the sill has been discussed. Furthermore, an experimental formula for the drag force acting on the sill has been proposed considering the characteristics of the flow condition over the sill. RESUME L'étude experimental des pressions aux parois a été réalisée sur un seuil mince vertical, dans le but de définer les caractéristiques d'un bassin de dissipation a ressaut force. La nature de la distribution des pressions sur les deux faces verticales du seuil a été discutée, et une loi empirique a été proposée pour calculer l'effort de trainee s'exercant sur le seuil a partir des conditions d'écoulement sur ce dernier.

Hydraulic jumps on rough and smooth beds: aggregate approach for horizontal and adverse-sloped beds

“…McCorquodale & Mohamed (1994) proposed a theoretical approach based on conservation of momentum principles to estimate hydraulic jump characteristics and found that the stability of a hydraulic jump on an adverse slope is also dependent on the upstream Froude number. The presence of a sill increases hydraulic jump stability for both horizontal (Hager & Bretz, 1988;Othsu, 1981;Ohtsu, Yasuda, & Yamanaka, 1991) and adverse-sloped beds (Pagliara & Peruginelli, 2000). In particular, Pagliara & Peruginelli (2000) conducted a series of experimental tests with and without a sill, varying the bed slope from 0 to -20% (adverse slope).…”

Numerical and physical modelling approaches to the study of the hydraulic jump and its application in large-dam stilling basins

“…where is the distance between the hydraulic jump toe and the upstream face of the sill and the hydraulic jump length is obtained as = 5.5 2 * . The drag coefficient obtained for the presented models using the definition by Ohtsu et al [76] was in the line of their experimental results.…”

“…In particular, the research by Rahmeyer discussed several alternate designs to replace the full height sidewalls of the basin. Ohtsu et al [76] conducted an experimental study to determine the drag force on stilling basin sills. On the basis of their observations, these authors proposed an expression to obtain the drag coefficient, which was used to contrast the results of this research (section 5.5).…”

“…Nevertheless, Ohtsu et al [76] conducted an experimental research on the drag on vertical sills of stilling basins. On the basis of their experimental observations they proposed the following expression:…”

Experimental Analysis of Hydraulic Jump at High Froude Numbers

“…In addition, in the past studies, the effect of sill height on energy dissipation ratio, turbulence intensity, the length of hydraulic jump and roller was not examined in the case of the same Froude number. In addition, while the hydraulic jump occurring after the sluice gate was examined in the previous studies, in this study the hydraulic jump is evaluated in the stilling basin after the spillway chute channel ( [33,34,12,35,36,21,37]. For these reasons, this study has differences from the existing literature, and it is thought to contribute to the literature.…”