基于CFD-PID方法的仿生鱼自推进运动研究

Research on Self-Propelled Motion of Bionic Fish by CFD-PID Method

相较于传统的螺旋桨推进方式,水下仿生推进具有灵活、高效及对环境干扰小等优势。该文在求解不可压N-S方程和牛顿第二定律的基础上,嵌入PID控制算法,构建CFD-PID求解器,模拟主动控制下的仿生鱼自推进运动。通过PID算法动态调节仿生鱼摆幅,间接控制其速度,使仿生鱼可以达到任意特定的收敛速度。与常规方式自推进相比,PID控制自推进能更快地加速到预定速度,且在加速时期产生更大尺度的涡,最终的动态平衡状态则与常规方式自推进一致。

Underwater bionic propulsion has several advantages over traditional propeller propulsion methods, such as flexibility,efficiency, and less environmental impact. In this paper, on the basis of solving the incompressible N-S equation and Newton's second law, the PID control algorithm is embedded, and the CFD-PID solver is constructed to simulate the self-propelled motion of the bionic fish under active control. The speed of the bionic fish is indirectly controlled by dynamically adjusting the foil amplitude through a PID controller, allowing it to achieve any specific convergence velocity. Compared with conventional self-propulsion,PID-controlled self-propulsion can accelerate to a predetermined velocity faster, generate larger-scale vortices during the acceleration period, and achieve a dynamic equilibrium state that is consistent with conventional self-propulsion.