scholarly journals Analysis of the Flow in a Typified USBR II Stilling Basin through a Numerical and Physical Modeling Approach

Water ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 227 ◽  
Author(s):  
Juan Francisco Macián-Pérez ◽  
Rafael García-Bartual ◽  
Boris Huber ◽  
Arnau Bayon ◽  
Francisco José Vallés-Morán
Keyword(s):  
Physical Model ◽  
Hydraulic Jump ◽  
Numerical Approach ◽  
Free Surface Flows ◽  
United States Bureau ◽  
Bureau Of Reclamation ◽  
Stilling Basin ◽  
Modeling Approach ◽  
Stilling Basins ◽  
Energy Dissipation Devices

Adaptation of stilling basins to higher discharges than those considered for their design implies deep knowledge of the flow developed in these structures. To this end, the hydraulic jump occurring in a typified United States Bureau of Reclamation Type II (USBR II) stilling basin was analyzed using a numerical and experimental modeling approach. A reduced-scale physical model to conduct an experimental campaign was built and a numerical computational fluid dynamics (CFD) model was prepared to carry out the corresponding simulations. Both models were able to successfully reproduce the case study in terms of hydraulic jump shape, velocity profiles, and pressure distributions. The analysis revealed not only similarities to the flow in classical hydraulic jumps but also the influence of the energy dissipation devices existing in the stilling basin, all in good agreement with bibliographical information, despite some slight differences. Furthermore, the void fraction distribution was analyzed, showing satisfactory performance of the physical model, although the numerical approach presented some limitations to adequately represent the flow aeration mechanisms, which are discussed herein. Overall, the presented modeling approach can be considered as a useful tool to address the analysis of free surface flows occurring in stilling basins.

scholarly journals Experimental Characterization of the Hydraulic Jump Profile and Velocity Distribution in a Stilling Basin Physical Model

Water ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1758
Author(s):  
Juan Macián-Pérez ◽  
Francisco Vallés-Morán ◽  
Santiago Sánchez-Gómez ◽  
Marco De-Rossi-Estrada ◽  
Rafael García-Bartual
Keyword(s):  
Free Surface ◽  
Energy Dissipation ◽  
Velocity Distribution ◽  
Physical Model ◽  
Hydraulic Jump ◽  
Surface Profile ◽  
Air Entrainment ◽  
Stilling Basin ◽  
Free Surface Profile ◽  
Stilling Basins

The study of the hydraulic jump developed in stilling basins is complex to a high degree due to the intense velocity and pressure fluctuations and the significant air entrainment. It is this complexity, bound to the practical interest in stilling basins for energy dissipation purposes, which brings the importance of physical modeling into the spotlight. However, despite the importance of stilling basins in engineering, bibliographic studies have traditionally focused on the classical hydraulic jump. Therefore, the objective of this research was to study the characteristics of the hydraulic jump in a typified USBR II stilling basin, through a physical model. The free surface profile and the velocity distribution of the hydraulic jump developed within this structure were analyzed in the model. To this end, an experimental campaign was carried out, assessing the performance of both, innovative techniques such as the time-of-flight camera and traditional instrumentation like the Pitot tube. The results showed a satisfactory representation of the free surface profile and the velocity distribution, despite some discussed limitations. Furthermore, the instrumentation employed revealed the important influence of the energy dissipation devices on the flow properties. In particular, relevant differences were found for the hydraulic jump shape and the maximum velocity positions within the measured vertical profiles, when compared to classical hydraulic jumps.

Radial flow stilling basins with baffle blocks

1989 ◽  
Vol 16 (4) ◽  
pp. 489-497 ◽  
Author(s):  
Peter C. Nettleton ◽  
John A. McCorquodale
Keyword(s):  
Key Words ◽  
Hydraulic Jump ◽  
Water Surface ◽  
Radial Flow ◽  
Surface Profile ◽  
Hydraulic Jumps ◽  
Bureau Of Reclamation ◽  
Stilling Basin ◽  
Jump Length ◽  
Stilling Basins

A total of 120 tests of forced radial flow hydraulic jumps have been analyzed in order to develop curves and equations for the design of radial stilling basins. The jump depth, the water surface profile, wave amplitudes, the allowable flare angle, and the jump length are defined in terms of entrance conditions, the baffle position, and the baffle height. An example design is given and compared with a USBR (U.S. Bureau of Reclamation) Type III stilling basin. Key words: forced hydraulic jump, radial flow, design, stilling basins, baffles, radial hydraulic jump, circular hydraulic jump.

USBR Type III and Type IV Stilling Basins and Rock Aprons Associated with Stepped Chutes

2018 ◽  
Vol 34 (2) ◽  
pp. 389-394
Author(s):  
Sherry L. Hunt ◽  
Kem C. Kadavy
Keyword(s):  
Research Unit ◽  
Stepped Spillways ◽  
Engineering Research ◽  
Bureau Of Reclamation ◽  
Stilling Basin ◽  
Type Iii ◽  
Design Engineers ◽  
Type Iv ◽  
Rock Stability ◽  
Stilling Basins

Abstract. Stilling basins are commonly used as energy dissipators for structural chutes. Classical research conducted by scientists of the U. S. Bureau of Reclamation (USBR) led to the development of design criteria for a variety of stilling basin configurations as the outlet works for smooth chutes, but little is known about the performance of these dissipators when paired with stepped chutes. Research at the USDA-ARS Hydraulic Engineering Research Unit (HERU) in Stillwater, Oklahoma, was conducted on USBR Type III and Type IV stilling basins with rock aprons located downstream of a near prototype stepped chute. Data indicates Froude numbers based on the incoming clear water flow depth to the stilling basin range from 3.3 = F = 5.5. Visual observations noted during the tests indicate acceptable performance of the Type III and Type IV stilling basins when operated at recommended or greater tailwater settings as set forth by the USBR. Three methods, the Isbash, USBR, and USGS, were chosen for evaluating the rock stability of the rock aprons placed downstream of the endsill of the stilling basins used in association with stepped chutes. Data indicate each method is suitable for riprap sizing of the rock apron. The intent of this research is to provide design engineers with knowledge regarding the performance of USBR Type III and Type IV stilling basins with rock aprons designed in conjunction with stepped chutes. Keywords: Dam safety, Embankment dams, Energy dissipation, Rock apron, Roller compacted concrete, Stepped spillways, Stilling basin.

scholarly journals The length of the hydraulic jump on the basis of physical and numerical modeling

2018 ◽  
Vol 50 (1) ◽  
pp. 33-42
Author(s):  
Janusz Urbański ◽  
Piotr Siwicki ◽  
Adam Kiczko ◽  
Adam Kozioł ◽  
Marcin Krukowski
Keyword(s):  
Numerical Modeling ◽  
Physical Model ◽  
Computational Fluid Dynamic ◽  
Hydraulic Jump ◽  
Fluid Dynamic ◽  
Sluice Gate ◽  
Ansys Fluent ◽  
Measured Velocity ◽  
Stilling Basin ◽  
Research Goal

Abstract The outcomes of physical and numerical modeling of the sluice gate outflow are presented. The measured velocity distributions in verticals of a physical model were compared with results of numerical modeling, obtained using ANSYS Fluent software. The research goal was verification of suitability of the computational fluid dynamic (CFD) approach in determination of the hydraulic jump length at the outflow of the flow control structure. Studies were performed for the model of the sluice gate and stilling basin with two setups of baffle blocks: in one and two rows. The jump lengths were estimated by an analysis of vertical velocity profiles at the outflow. Two rows of baffle blocks in the stilling basin allowed to reduce the length of the hydraulic jump by 5–10%, comparing to the length with the single row of blocks. The computational fluid dynamic approach underestimated the length of the hydraulic jump by 4–7%, comparing to the physical model.

Laboratory study of stilling basin using trapezoidal bed elements

2020 ◽  
Vol 29 (4) ◽  
pp. 409-420
Author(s):  
Thair Al-Fatlawi ◽  
Nassrin Al-Mansori ◽  
Nariman Othman
Keyword(s):  
Energy Dissipation ◽  
Laboratory Study ◽  
Hydraulic Jump ◽  
Stilling Basin ◽  
Smooth Model ◽  
Stilling Basins ◽  
Spillway Structures ◽  
Baffle Block ◽  
Pressure Driven

When designing dam spillway structures, the most significant consideration is the energy dissipation arrangements. Different varieties of baffle blocks and stilling basins have been used in this context. However, the hydraulic jump form of stilling basin is considered to be the most suitable. The main objective of this research was to introduce four different baffle block shapes (models arranged from A to D, installed at slopes 0.00, 0.04, 0.06 and 0.08 in the stilling basins). To illustrate the consequences for the qualities of pressure-driven bounce, each model was attempted in the bowl. The trials applied Froude numbers between 6.5 and 9.2. The puzzle square model D provided the best outcomes compared to the models A, B, C and smooth. Model D with different models at inclines 0.00, 0.04, 0.06 and 0.08 was used to consider the impacts of perplex hinders on water driven-bounce when bed slants were changed. When the model D baffle used instead of a smooth bed at 0.08 slope, the reduction in y2 / y1 reached 12.8%, and Lj / y1 was 18.9%. Among the different bed slopes, a normal decrease in y2 / y1 ranged from approximately 10.3%, whereas the normal decrease in Lj / y1 was about 13.8% when the model D baffle was used instead of the model A baffle with a horizontal slope bed of 0.00. The results show that the new shapes led to a decrease in sequent profundity proportion and length of jump proportion; however, the energy dissipation proportion increased.

scholarly journals Effect of baffle block configurations on characteristics of hydraulic jump in adverse stilling basins

2018 ◽  
Vol 162 ◽  
pp. 03005
Author(s):  
Ali Abbas ◽  
Haider Alwash ◽  
Ali Mahmood
Keyword(s):  
Energy Dissipation ◽  
Hydraulic Jump ◽  
Block Model ◽  
Double Row ◽  
Stilling Basin ◽  
Depth Ratio ◽  
Stilling Basins ◽  
Sequent Depth ◽  
Baffle Block ◽  
Energy Dissipation Ratio

The construction of stilling basin with adverse slope change the characteristics of hydraulic jump such as sequent depth ratio, length of jump ratio, length of roller and energy dissipation ratio, consequently the dimensions of stilling basin are changed, also using baffle blocks with different configurations develop these characteristics. In this study different shapes of baffle block (models (A), (B), (C) and (D)) installed in the stilling basins at adverse slopes (- 0.03, - 0.045, - 0.06) in addition to horizontal bed, all these models are tested in the stilling basin to show their effects on the characteristics of hydraulic jump, the experiments applied for the range of Froude number (Fr1) between 3.99 and 7.48. The baffle block model (D) showed good results when compared with models (B) and (C), therefore it used with arrangement of (single and double row) and compared with baffle block model (A) at slopes (0, - 0.03, - 0.045, - 0.06) to study the effects of baffle blocks on hydraulic jump when bed slopes are changed. In general using baffle block caused a reduction in sequent depth ratio, length of jump ratio and the length of the roller, but the energy dissipation ratio increased.

ESTIMATION OF HYDRAULIC JUMP CHARACTERISTICS IN STILLING BASIN WITH GUIDE WALLS

2012 ◽  
Vol 40 (6) ◽  
pp. 1599-1609
Author(s):  
Habib A.A. ◽  
Abdel-Azim M. Ali ◽  
Abd-Allh Y.M ◽  
Saleh y.k.
Keyword(s):  
Hydraulic Jump ◽  
Stilling Basin

Discussion of “Upward Pressures under Dams: Experiments by the United States Bureau of Reclamation”

1929 ◽  
Vol 93 (1) ◽  
pp. 1551-1580
Author(s):  
E. L. Chandler ◽  
B. F. Jakobsen ◽  
Charles Terzaghi ◽  
J. C. Stevens ◽  
F. W. Hanna ◽  
...  
Keyword(s):  
United States ◽  
The United States ◽  
United States Bureau ◽  
Bureau Of Reclamation
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