循环水养殖池内鱼类运动数值模型的建立——以许氏平鲉为例

Numerical modeling of fish movement in a recirculating aquaculture tank:in the case of Schlegel's black rockfish Sebastes schlegelii

为探索柔性鱼体运动对养殖池内流场特性的影响,以许氏平鲉Sebastes schlegelii作为仿生对象,分别采用Auto CAD和Solidworks建立二维和三维鱼体仿真运动模型,并将模型接入Fluent模块中建立鱼类-流体间的流固耦合数值模型,基于UDF宏文件编写程序,采用动网格技术以二维平面中尾鳍摆动为基础定义三维空间内鱼体的摆尾波动。结果表明:使用建模软件建立的二维及三维模型可通过软件接口导入ANSYS中用于仿真计算,基于鲹科运动方程编写的UDF宏文件可用于定义仿生鱼运动;数值模型的仿真结果显示,养殖池内鱼尾的摆动会在尾部末端形成一系列的脱落涡,进而对其周围流场产生一定影响。研究表明,本文建立的鱼类运动仿生模型可反映出鱼类对流场的影响,该仿生研究方法可拓展建立其他鱼类运动模型并开展应用研究。

In order to explore the influence of flexible fish movement on the characteristics of flow field in an aquaculture tank,the two-dimensional and three-dimensional simulated fish movement models of Schlegel's black rockfish Sebastes schlegelii were established by Auto CAD and Solidworks,respectively.The fluid-structure coupling numerical model between fish and fluid was established by connecting the model into Fluent module,and the program was written based on UDF macro.The swinging tail wave of fish in 3D space was defined by the moving grid technology based on the swinging tail fin in 2D plane.The results showed that 2d and 3D models established by modeling software were imported into ANSYS through the software interface for simulation calculation.UDF macro based on wave equation of Scad was used to define the movement of bionic fish.Numerical simulation of the bionic modeling showed that the motion of the tail in the fish formed a series of shedding vortex in the end of the tail,and impacted on the flow field around it.The findings showed that the bionic fish movement based on the method to establish model reflected the influence of fish flow field,and that the bionic research method expanded the other fish motion model establishment and applied in research.