A novel muscle-driven method (MDM) with its corresponding Compute Unified Device Architecture parallel computational code is newly developed to mimic shortening and lengthening of muscles, in a fish-like swimming body, which causes the body flapping in the transversal direction and create a thrust force to propel the body to cruise in the longitudinal direction. In this method, the fish body is discretized as mass points connected by elastic springs and muscle deformation is critically realized by using a constraint algorithm, called RATTLE, to control relative deformation distances between neighboring mass points of the muscles, while turbulent fluids are treated by a multi-relaxation time lattice Boltzmann method with a large eddy simulation. A validation for the MDM is extensively conducted by comparing our simulation results with the existing experimental and theoretical results. Subsequently, the frequency, amplitude, and wavelength of lengthening of muscles and the stiffness and mass density of the body are systematically varied at different levels and their effects on flapping and cruising motion and flow structures are studied at different Reynolds numbers.

中文翻译：

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一种肌肉驱动游泳的模拟方法及其应用

新开发了一种新的肌肉驱动方法 (MDM) 及其相应的计算统一设备架构并行计算代码，以模拟鱼状游泳身体中肌肉的缩短和延长，从而导致身体横向拍打并创建一个推动机体沿纵向巡航的推力。在该方法中，将鱼体离散为由弹性弹簧连接的质点，并通过使用称为 RATTLE 的约束算法来控制肌肉相邻质点之间的相对变形距离，从而严格实现肌肉变形，而湍流流体则通过具有大涡模拟的多弛豫时间格子 Boltzmann 方法。通过将我们的模拟结果与现有的实验和理论结果进行比较，对 MDM 进行了广泛的验证。随后，肌肉伸长的频率、幅度和波长以及身体的刚度和质量密度在不同水平上系统地变化，并研究了它们在不同雷诺数下对扑翼和巡航运动和流动结构的影响。