Simulation Of Lake Wind-waves Based On CFD And Study Of Wave Dissipation At Floating Dock

China has abundant lake resources and accounts for the third place in the world.The abundant lake resources occupy a very important position in the water,shipping,tourism and hydropower engineering fields.However,wind-waves often threaten the ships navigation,stable berthing,and the safety of buildings in the lake.Sometimes it may even cause huge economic losses and casualties.Therefore,research on the wind-waves in the lake is particularly important.With the rapid development of computer computing performance,CFD(Computational Fluid Dynamics)has grown continuously,and numerical simulation of wind-waves has become a major research method.At present,most of the studies on the numerical simulation of wind-waves are based on the study of wind-waves in the sea,and there are few studies on wind-waves in small wind areas such as lakes and reservoirs.In this paper,combines theoretical research with practical application.Taking the floating dock of the deep-water lake of the Fuxian Lake in Yuxi city as example,a mathematical model of the wind-wave in the lake is established.And the laws of distribution and propagation of wave elements in the lake under different wind conditions are analyzed.Under the influence of different wind conditions,the most unfavorable conditions affecting the operation of the floating dock and the steady berthing of the ship in the lake are determined,and the main factors influencing the change of wave height in the lake is revealed.Therefore,different wave elimination schemes are used to study wave attenuation performance of floating docks under most unfavorable conditions in the lake,and the wave elimination results of different wave breaking schemes are compared and analyzed to determine most superior scheme of wave attenuation of floating breakwater,a reference for optimization of floating breakwater is provided,providing the security for the safe of building and the navigation and steady berthing of ships in the lake.The main research content is summarized below:(1)Staring from the theory of fluid mechanics,the research methods of wind-wave,the structural types of floating breakwaters,and methods of wave elimination were reviewed.The development of wind-wave numerical models and the limitations of their respective models were summarized,and the generation mechanismof wind-wave was analyzed.And the main cause of damage to the breakwaters in the Lake.(2)Based on the Mike 21 SW model,a mathematical model of the wind-wave in the lake was established.The simulation results were validated using empirical formulas such as Putian formula,SMB method,and standardized method widely used in practical projects in the lake to prove that he availability ofthe Mike 21 SW model was in deep-water lakes.Analyzing the wave conditions of the lake under different wind load conditions.Studying the variation of wave height in the lake under different wind speeds and different water levels.The main influencing factors of the change of wave height in the lake were revealed,and the most unfavorable conditions that threaten the safety of floating docks in the lake and the navigation of ships under different wind conditions were determined.(3)Under the most unfavorable conditions,schemes of different wave attenuation(such as layouts of floating breakwater,angles of floating breakwater,lengths of floating breakwater,widths of floating breakwater,and types of floating breakwater,etc.)on the effect of wave attenuation performance of floating breakwater were studied,and different wave attenuation schemes were compared to propose most superior scheme of arrangement of floating breakwaters,the wave attenuation performance of most superior scheme of arrangement of floating breakwaters was analyzed.