水流作用下平面金属网衣水阻力特性数值模拟

Numerical simulation on hydrodynamic characteristics of the plane metal net under current

为研究养殖用金属网衣多孔小直径网状结构的水动力响应特性,采用计算流体动力学原理,基于Navier-Stokes方程及大涡模拟(LES)湍流模型,并运用ABAQUS/CFD模块中的Gauss-Seidel耦合方法进行了水流作用下网衣的流固耦合计算,在试验验证的基础上,得到了不同目脚尺寸和网线直径组合条件下锌铝合金网衣的平面受力计算结果。结果表明:当网衣目脚尺寸由25 mm增加到35、45 mm时,3种网线直径对应的网衣受到的水阻力值平均减小幅度分别为29.15%和43.79%;当网线直径由2.5 mm增加到3.2、4.0 mm时,3种目脚尺寸对应的网衣受到的水阻力值平均增加幅度分别为27.01%和55.84%。本研究结果可为进一步探究金属网箱在波流作用下的整体受力变形提供理论参考。

In order to study the hydrodynamic characteristics of the metal net in aquaculture,which is a special kind of porous net structure with small diameter,the computational fluid dynamics was used in the force calculation of the plane net. Based on the Navier-Stokes Equation and the turbulence model of Large Eddy Simulation （ LES）,the fluid-structure interaction was simulated by the Gauss-Seidel method in the ABAQUS/CFD model. Verified by the experiment,the force on the plane net with different net size and different thread diameter was computed and analyzed. The simulation results showed that when the net size increased from 25 mm to 35 mm,and 45 mm,the drag forces of the net with three different diameter thread were decreased by 29. 15% and 43. 7 9 % respectively. When the thread diameter increases from 2. 5 mm to 3.2 mm,and 4. 0 mm,the average increase of drag forces of the net with three different net size were increased by 27. 0 1 % and 55. 8 4 % respectively. The results provide a theoretical reference for the further study of the metal cage under the action of wave current.