Simulations of Moving Effect of Coastal Vegetation on Tsunami Damping
Ching-Piao Tsai, Ying-Chi Chen, Tri Octaviani Sihombing, and Chang Lin
Department of Civil Engineering, National Chung Hsing University, Taichung 402, Taiwan
Received: 01 Nov 2016 – Accepted for review: 18 Dec 2016 – Discussion started: 23 Dec 2016
Abstract. A coupled wave-vegetation simulation is presented for the moving effect of the coastal vegetation on tsunami wave height damping. The problem is idealized by solitary wave propagating on a group of emergent cylinders. The numerical model is based on general Reynolds-averaged Navier-Stokes equations associated with renormalization group turbulent closure model by using volume of fluid technique. The general moving object (GMO) model developed in CFD code Flow-3D is applied to simulate the coupled motion of vegetation with wave dynamically. The damping of wave height and the turbulent kinetic energy dissipation as waves passed over both moving and stationary cylinders are discussed. As comparing with the stationary cylinders, it obtains markedly less wave height damping and turbulent kinetic energy dissipation by the moving cylinders. The result implies that the wave decay by the coastal vegetation might be overestimated if the mangrove vegetation was represented as stationary state.
Tsai, C.-P., Chen, Y.-C., Sihombing, T. O., and Lin, C.: Simulations of Moving Effect of Coastal Vegetation on Tsunami Damping, Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-353, in review, 2016.