NUMERICAL SIMULATION OF BATOID LOCOMOTION

• Published in: Journal of hydrodynamics. Series B Vol. 23; no. 5; pp. 594 - 600
• Main Authors: CHEN, Wei-shan, WU, Zhi-jun, LIU, Jun-kao, SHI, Sheng-jun, ZHOU, Yang
• Format: Journal Article
• Language: English
• Published: Singapore Elsevier Ltd 01.10.2011; Springer Singapore; State Key Laboratory of Robotics and System, Harbin Institute of Technology, Harbin 150001, China
• Subjects: Amplitudes; batoid fish; Computer simulation; dynamical simulation; Engineering; Engineering Fluid Dynamics; Fins; Fluid flow; Hydrology/Water Resources; Locomotion; Mathematical analysis; Mathematical models; Navier-Stokes equations; Numerical and Computational Physics; Simulation; Stokes方程; undulation pectoral fin; 三维模拟; 振幅变化; 推力系数; 推进机构; 数值模拟; 游泳运动; 用户定义函数; dynamical simulation; undulation pectoral fin; batoid fish
• ISSN: 1001-6058; 1878-0342
• DOI: 10.1016/S1001-6058(10)60154-0

The hydrodynamics of batoid swimming motions is investigated using the three-dimensional simulation of a self-propelled body in still water. The kinematics of batoid swimming is characterized by large amplitude undulations of the pectoral fins while the middle part of the body remains straight. The majority of the thrust is generated by pectoral fins. Linear and quadratic amplitude variations are used for the pectoral fins in analyzing the locomotion of the batoid. Navier-Stokes equations are used to solve the unsteady fluid flow. A user defined function and a dynamic mesh method are applied to track the batoid locomotion. The mean swimming velocities of 1.6 BL/s and 1.3 BL/s are achieved, respectively, with thrust coefficients of 0.13 in and 0.095 in the dynamical simulation, where BL/s is the body length per second. The maximum propulsive efficiency 19% is achieved when the frequency of the undulation is 2.2 Hz in both amplitude variations.