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Energy Loss Coefficient of Waves Considering Thickness of Perforated Wall  

Yoon, Sung-Bum (Department of Civil and Environmental Engineering, Hanyang University)
Lee, Jong-In (Korea Institute of Construction Technology)
Nam, Doo-Hyun (Daeyoung Engineering Co. Ltd.)
Kim, Seon-Hyung (Department of Civil and Environmental Engineering, Hanyang University)
Publication Information
Journal of Korean Society of Coastal and Ocean Engineers / v.18, no.4, 2006 , pp. 321-328 More about this Journal
Abstract
In the present study extensisve numerical experiments are conducted using the CFD code, FLUENT, to investigate the energy dissipation due to perforated walls for various wall-thickness and flow conditions. A new empirical formula for energy loss coefficient considering the effect of the thickness of perforated wall is obtained based on the results of computational experiments. It is found that the energy loss coefficient decreases as the wall-thickness increases and the maximum coefficient reduction reaches upto 40% of the value calculated using the conventional formulas for the sharp-crested orifice. To check the validity of the new formula the reflection coefficient of waves due to perforated wall is evaluated and compared with the results of existing theories and hydraulic experiments. The result shows that the new formula is superior to the conventional ones.
Keywords
perforated wall; reflection coefficient of wave; energy loss coefficient; thickness of wall; CFD;
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