四棱台透水框架水动力特性试验研究

Experimental study on hydrodynamic characteristics of tetrahedron permeable frames

基于鱼礁概念,提出一种新型四棱台透水框架结构,并开展系列水槽试验,利用剖面流速仪ADCP(acoustic doppler current profilers)测量四棱台透水框架防护区周围流场结构,分析架空率对透水框架周围水流结构的影响,研究四棱台透水框架对防护区周围的水动力特性影响。试验结果表明:四棱台透水框架防护后水流上下速度分布差异更为明显,框架层流速显著减小,且流速减小幅度随架空率的减小而增大;紊动强度分布出现拐点,拐点位置与架空率具有明显的相关性,紊动强度随架空率的减小而增大;防护区内部近底处存在紊动收敛区域,其紊动强度随架空率减小而减小。

A new type of tetrahedron permeable frame was proposed based on the concept of fish shelter,and experiments on the flow characteristics around the protected area were conducted using acoustic doppler current profilers(ADCP).Then,the influences of overhead rates on the flow structure and hydrodynamic characteristics were discussed.The experimental results show that the difference of velocity distributions between the top and bottom of flow is more obvious.The flow velocity of the frame layer is obviously reduced,and the decrease rate of the flow velocity increases with the decrease of the overhead rate.An inflection point appears in the turbulence intensity distribution,and its position has a distinct correlation with the overhead rate.In addition,the turbulence intensity increases with the decrease of overhead rate too.There is a turbulent convergence zone near the bottom of the protective zone,and the turbulence intensity of this zone decreases with the decrease of the overhead rate.