Numerical Simulation Of Flexible Plant Effects On Wave Propagation Along The Slope

At present,a part of the coastal zone is not protected,or most of which adopt the traditional hard structure protection;while the new soft structure,combined with the coastal plant,has the advantages of changing the hydrodynamic structure,promoting the deposition of the beach,stabilizing the original beach and preventing erosion.Therefore,the establishment of mixed structure revetment or soft structure revetment for coastal zone repair or protection can meet the economic and environmental requirements.It is of great significance for the design and construction of new revetment to explore the influence of vegetation and wave elements on the coastal protection effect and predict the change of wave propagation process under the influence of vegetation.In this paper,an additional frictions added to the N-S equation,and the vegetation motion model is introduced to establish the equivalent attenuation theoretical model of wave climbing along the slope under the wave-flexible vegetation interaction.The equations are dispersed by finite difference method and MAC method to track the water particle movement on the free surface;and the vegetation movement equation is solved by the superposing the main vibration which transformed by regular coordinate.The calculation process is realized by FORTRA,and the results are processed by MATLAB.Taking the wave propagation along 1 / 30 slope as an example,the changes of wave surface and flow field with or without vegetation are compared,and the role of flexible vegetation in wave propagation is analyzed.Finally,the influences and laws of vegetation characteristics(diameter,height,vegetation density and vegetation elastic strength)and wave characteristics(relative wave height,relative water depth and wave steepness)on the wave attenuation are discussed respectively,which provides a reasonable reference for the selection and design of vegetation in the actual revetment engineering.