Enhancement of Energy Dissipation by Using Different Shape of Baffle Block - A Review

The stilling basin has been one of the most powerful hydraulic structures for the dissipation of the flow energy. Meshfree and particle methods have special advantages in modeling incompressible flows with free surfaces. In this paper, an integrated smoothed particle hydrodynamics (SPH) method is developed to model energy dissipation process of stilling basins. The integrated SPH includes the kernel gradient correction (KGC) technique, the dynamic solid boundary treatment, [Formula: see text]-SPH model and density reinitialization. We first conducted the simulations of dam-breaking and hydraulic jump to validate the accuracy of the present method. The present simulation results agree well with the experimental observations and numerical results from other sources. Then the discharge process of stilling basin with baffle-blocks is simulated with the integrated SPH. It is demonstrated that the detailed discharge process can be well captured by this method. The energy dissipation effect of stilling basin could be significantly improved by the baffle-blocks. The structure and position of the baffle-block directly affect the energy dissipation effect, while the height of the baffle-block has big influence on the drainage capacity.

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The Effects of Different Shaped Baffle Blocks on the Energy Dissipation

Civil Engineering Journal ◽

10.28991/cej-2020-03091521 ◽

2020 ◽

Vol 6 (5) ◽

pp. 961-973

Author(s):

Nassrin Jassim Hussien Al-Mansori ◽

Thair Jabbar Mizhir Alfatlawi ◽

Khalid S. Hashim ◽

Laith S. Al-Zubaidi

Keyword(s):

Energy Dissipation ◽

Hydraulic Jump ◽

Concrete Block ◽

Naval Research ◽

Irrigation Systems ◽

Force Ratio ◽

Stilling Basins ◽

Baffle Block ◽

Length Reduction ◽

Better Than

Stilling basins can be defined as energy dissipaters constructed of the irrigation systems. This study aims at investigating the performance of the new seven baffle blocks design in terms of reducing the dimensions of stilling basins in irrigation systems. In order to assess the hydraulic efficiency of a new model for baffle block used in stilling basins, a Naval Research Laboratory (NRL) has conducted. The results of this study demonstrate that the performance of the new baffle block, in term of hydraulic jump length reduction and hydraulic energy dissipation, it's better than standard blocks. However, the ratios of the drag resistance attributed to the new baffles block (FB / F2) have been larger than that applied on the normal block. It was found that the new block dissipates the energy by 9.31% more than the concrete block, and decreases the length of the hydraulic jump by 38.6% in comparison with the standard blocks. However, the new block maximizes the drag force ratio by 98.6% in comparison with the standard baffle blocks. The findings indicated that in terms of energy reduction and dissipation in the length of the hydraulic jump, the new block is superior to the other kinds.

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Laboratory study of stilling basin using trapezoidal bed elements

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska ◽

10.22630/pniks.2020.29.4.35 ◽

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.

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

MATEC Web of Conferences ◽

10.1051/matecconf/201816203005 ◽

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.

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