| The breakwater is an important marine protection engineering structure,which has the function of resisting waves and can protect the safety of ships,marine aquaculture facilities and other marine structures in the water area.The traditional breakwater is a bottomed breakwater with excellent wave absorbing performance.However,it is expensive and requires high foundations,which can easily lead to silt accumulation.Compared with traditional bottom-mounted breakwaters,floating breakwaters have the characteristics of diversified structures and functions,low engineering cost,easy installation and disassembly,and allow water quality point exchange without causing pollution to the environment and affecting the ecological environment.It has been paid more and more attention by more scholars and researchers.In this paper,Savonius blades are arranged and installed on the basis of the double-buoy breakwater,and the wave absorbing performance,energy capturing performance and mooring force of the new breakwater are studied.The main research contents include:1、 Based on the theory of viscous fluids,using STAR-CCM+ software,the regular wave is numerically simulated and the calculated wave values are compared with the theoretical values to verify the correctness of the numerical wave flume.On this basis,according to the principle of boundary wave method and the damping wave principle,establish a three dimensional numerical model of Savonius floating breakwater,the turbulence model,overlapping grid technique,six degrees of freedom motion model,VOF free surface capture technology in gas liquid two phase flow within the computational domain calculation,to calculate transmission coefficient,reflex coefficient,mooring force as well as monitoring of blade can capture performance.2、 According to the numerical simulation of STAR-CCM+,combined with the working conditions of the experimental site,a floating breakwater based on Savonius-type blades was designed and manufactured.The blades were suspended under the double floating tube floating body to achieve the capture of wave energy below the water surface.By combining Savonius-type blades,the overall moment of inertia of the floating breakwater is increased,and the wave suppression performance is improved.3、 Propose a plan for a floating breakwater based on Savonius-type blades,determine the mooring method,design the transmission structure,and conduct a comparative analysis of the wave suppression performance and energy capture performance of the traditional double-buoy breakwater and the new Savonius breakwater through physical experiments.The results show that the new type of floating breakwater with double-row Savonius impellers increases the cross-section of wave elimination,and has excellent performance for short period wave elimination.The power of energy capture is obviously affected by wave period,and the mooring force decreases obviously in the optimal region of energy capture.4、 Based on the numerical wave tank and the physical experimental model,the structural parameters of the floating breakwater with Savonius-type paddles are optimized,including the paddle size and water penetration depth,and the optimal depth of entry of the paddles is obtained by adjusting the installation position first,and then the energy capture performance and wave dissipation performance of the flexible breakwater under different wave conditions are studied by changing the paddle size.The results show that when the relative water penetration depth is 0.65 D,the blade is in the best energy harvesting range.When the wave period is close to the rotation period of the blade,it has a better energy capture performance.As the period of the incident wave increases,the size of the blade should be appropriately increased. |
PDF Full Text Request