The Role of CFD Technique in the Effect of Baffle Blocks on Flow Dynamics

Year 2024, Volume: 5 Issue: 2, 70 - 76, 30.12.2024

Mahmut Aydoğdu

https://doi.org/10.46572/naturengs.1592272

Abstract

A flow with a high amount of hydraulic energy causes high velocities in the flow while passing downstream of the water structure, thus creating high pressure and friction conditions. As a result, problems such as erosion, abrasion, and cavitation may occur on the water structure or downstream. Not taking precautions causes the water structure to be destroyed completely or the surrounding facilities and structures to suffer serious damage. Energy-dissipating structures are constructed in field applications to bypass such negative situations. Blocks placed especially on chute channels or inside stilling basins are quite effective in dissipating the energy of the flow. These blocks dissipate the energy of the flow by creating turbulence inside. Sometimes the flow hits the blocks, and sometimes the blocks separate the flow, creating turbulence. The aim is to reduce the supercritical velocities to subcritical. It can only be achieved by providing a hydraulic jump. Within the scope of this study, a T-shaped block that can be used in the stilling basins was designed. Such a block type was preferred to increase the surface areas of the flow hitting the blocks and thus to observe the energy-dissipating situation. In the literature, similar block types were used in some previous studies. However, some flow dynamics parts that could not be measured experimentally were missing. Therefore, this deficiency was tried to be eliminated by modeling channel and block structures in a digital environment using today's computer and software technology. Firstly, this block type was modeled in a digital environment as a single-row and double-row block array, and energy-dissipating situations were observed. For this purpose, Ansys-Fluent software, which is widely used in Computational Fluid Dynamics (CFD), was preferred. The created model was designed in 3D and numerical solutions were obtained. According to the results of the study, the turbulence values effective in energy-dissipating were easily obtained. In addition, it was observed that the single-row block array dissipates more energy in the digital environment at a lower cost. Before moving on to field applications of this study, it can be said that it will be an important base in determining the flow-block interactions that cannot be measured experimentally.

Keywords

baffle block,, energy dissipation,, open channel,, turbulence

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