Characterizing Korean general artificial reefs by drag coefficients

This study presents the processes for acquiring the drag coefficients of 24 representative Korean general artificial reefs (ARs), identifying (or excluding) some ARs having unusual ratios, grouping the ARs into three combinations, and characterizing the combinations with respect to the dimensionless characteristics, which related to the wall area, front velocity, and height. For the purpose, finite volume-based flow analysis was carried out by applying inlet, outlet, smooth wall, and symmetric boundary conditions. From the results, it is shown that the processes give a simpler way to estimate the drag coefficients - formula as functions of the characteristics. Therefore, this study gives ones how to identify, estimate, or characterize a newly developed artificial reef by simply using the characters of the existing 24 general ARs. In addition, it is found that the variation of the initial flow velocity does not change the drag coefficients but it is shown that the variation of the angle between the flow and AR directions does significantly change the drag coefficients.