Investigation On Mean Overtopping Rate Of Sloping Breakwater With Accropode Armor Blocks

Mean overtopping rate is a controlling index in the design of sloping breakwater,which is related to the safety of land area behind sloping breakwater and the structure of breakwater body.In recent years,accropode armor blocks has been widely used in the sloping breakwater design,but the current "Hydrological Code for Ports and Channels" lacks the criteria for calculating the mean overtopping rate of sloping breakwater with accropode armor blocks.From the previous research results,we can see that there are many factors whicn affect the mean overtopping rate of sloping breakwater,and each formula has its own scope of application and limitations.Therefore,it is specially necessary to study the mean overtopping rate of sloping breakwater with accropode armor blocks.Based on two-dimensional wave flume physical model test,this paper systematically studies the relationship between the mean overtopping rate of sloping breakwater with accropode armor blocks and its main influencing factors under the condition of slope m=1.5.The physical model test was carried out in the State Key Laboratory of Coastal and Offshore Engineering of Dalian University of Technology.In this experiment,irregular waves are used and the spectrum of irregular waves is JONSWAP(?=3.3).Considering the factors such as the wave steepness,the relative water depth,the relative superelevation of embankment,the relative shoulder platform width,the relative shoulder platform height and the relative block size,the correlation between each factor and the mean overtopping rate of the sloping breakwater with accropode armor blocks is analyzed by controlling a single variable.The formulas for calculating the mean overtopping rate of the slope breakwater and the influence coefficient of the protective surface structure are given by using the non-linear fitting method.Comparing the calculated value of this formula with the experimental value of physical model,the results are in good agreement,which proves that the formula of this paper has better calculation accuracy.Comparing the calculated value of this formula with the experimental value of previous models,the relative error is smaller,which proves that the formula of this paper has better applicability.The study of physical model test is helpful to explore the formula for calculating the mean overtopping rate of slope breakwater with with accropode armor blocks.The research results have certain reference significance for engineering design and application.Finally,based on FLUENT software platform,the continuity equation of viscous fluid and Reynolds time-averaged Navier-Stokes equation are used as the basic governing equations.The RNG k-? model simulates turbulence effects.The fluid volume method(VOF)traces the free surface of fluid.By adding the source term of porous media to the momentum equation,the two-dimensional numerical wave flume with porous media model is established.Using the numerical flume,the relationship between the inertial resistance coefficient and the mean overtopping rate in the porous media model is calibrated by simulating the mean overtopping rate of the sloping breakwater with accropode armor blocks and the calculation formula of the inertial resistance coefficient is given.