NWT-DEM Coupled Numerical Analysis on Wave Attenuation due to Vegetation

Abstract

Jeong, Y.M.; Jeon, H.S.; Park, J.R.; Jeong, Y.H., and Hur, D.S., 2019. NWT-DEM coupled numerical analysis on wave attenuation due to vegetation. In: Lee, J.L.; Yoon, J.-S.; Cho, W.C.; Muin, M., and Lee, J. (eds.), The 3rd International Water Safety Symposium. Journal of Coastal Research, Special Issue No. 91, pp. 146-150. Coconut Creek (Florida), ISSN 0749-0208.In this study, the numerical wave tank (NWT) and discrete element method (DEM) coupled analysis method was used to investigate the wave control characteristics of eco-friendly and natural vegetation. To examine the effectiveness and validity of the coupled analysis method, the results were compared with the existing hydraulic model test results. Most of the existing studies used numerical analysis methods that cannot consider the kinetic characteristics of vegetation owing to the drag coefficient (CD) of vegetation. As such, this study reproduced the kinetic characteristics of vegetation (which have not numerically examined but can be seen in the hydraulic model tests) using the coupled analysis method, and examined the wave control characteristics of vegetation by comparing its behavior according to its characteristics (flexible and rigid). Through the coupled analysis method, it was confirmed that rigid vegetation has a 1.2%–12.2% higher transmission coefficient (KT) than flexible vegetation in terms of wave attenuation of the vegetation zone due to the kinetic characteristics of vegetation.