Bottom Flow Field Analysis Of Baffle-Type Breakwater In Wave Action

Breakwater,a kind of common port hydraulic structure,is an important part of the harbor.Breakwater is to resist the sea waves,break the impact of waves,protect the harbor pool,ensure the harbor water smooth,so that ships can berth and operate safely,prevent the harbor sediment deposition and shoreline erosion.According to the structure,breakwater can be divided into two types: light breakwater and heavy breakwater.Light breakwater has been developed in the past decade,including floating breakwater,permeable breakwater and air jet breakwater.The permeable breakwater consists of wave retaining structure and buttress.It is reasonable in material and economy,suitable for deep water and small wave.The structure types of the permeable dike are hollow box,inclined plate,flat plate and etc.Baffle permeable breakwater is a promising type of breakwater.Compared with the traditional solid breakwater,the baffle permeable breakwater has obvious advantages: simple structure,especially suitable for soft soil foundation,convenient construction,low cost;it has little influence on the tidal current and the adjacent upstream and downstream projects,because the lower part of the embankment is permeable;the structure of it is adaptable to the scouring and silting of the coast or riverbed and it can also be used as a dock to berth ship.Based on the finite volume method of open source software OpenFOAM,the article solve the continuity equation and momentum equations of incompressible fluid,and establish a two-dimensional numerical wave flume.This paper calculates the examples of the dam whose relative water entry depth(baffle entry depth/water depth)are 0.2,0.6,0.8.In this paper,the following flow field analysis is carried out for the open dike: firstly,the results of the calculation example are post-processed to obtain the velocity vector diagram,vel ocity cloud diagram and flow diagram in the next cycle under a kind of wave condition,and analyze and compare them.Secondly,the vertical distribution of the horizontal velocity in front of the front baffle was analyzed,and the horizontal velocity and vertical velocity were compared in one wavelength of the front baffle,so as to verify that it conforms to the flow field characteristics of vertical waves formed in front of the baffle.Finally,the influence of baffle permeable dike with relative water depth of permeable breakwater on transmission coefficient coefficient and max velocity in bottom of breakwater is studied.