[1] Ao Li, Yu-Xiao Luo, Yuan Liu ,Yuan-Qing Xu*, Fang-Bao Tian, Yong Wang, Hydrodynamic behaviors of self-propelled sperms in confined spaces.Engineering Applications of Computational Fluid Mechanics，2022，16:1, 141-160.
Description: A free-swimming model of a sperm population was built innovatively using the immersion boundary-lattice Boltzmann method. Based on the model, the
hydrodynamic mechanism of wall-adhension and rheotaxis of the sperm was discussed in detail. And a sperm population in a narrow space was studied to reveal the evolution laws of the sperm distribution and migration.
说明：创新性利用浸入边界-格子Boltzmann方法建立了精子群体自由游动模型。通过模拟精子群体在狭窄空间流动中的游动与分布规律，揭示了精子游动过程的贴壁性、趋流性的水动力学机理。
[2] Ao Li, Gao-Ming Xu, Jingtao Ma, Yuan-Qing Xu* . Study on the binding focusing state of particles in inertial migration[J]. Applied Mathematical Modelling, 2021, 97:1-18.
Description: This paper uses the same topological grid to establish three-dimensional spherical particles. By applying different mechanical mechanism models to describe the physical characteristics of their deformability. Reporting a coupling phenomenon called “binding focusing” between a couple of soft and hard particles. This potentially provides a new manipulation way for cell sorting based on the inertial focusing mechanism.
说明：通过利用相同的拓扑网格建立三维球形颗粒，利用不同的力学机理模型描述软颗粒和硬颗粒的物理学特性，通过将其惯性聚焦现象进行关联，发现了称之为“绑定聚焦”的流固耦合现象。为基于惯性聚焦机理的细胞分选提供了新的操控思路。
[3] Qiong-Yao Liu, Xiao-Ying Tang, Duan-Duan Chen, Yuan-Qing Xu*， Fang-Bao Tian. Hydrodynamic study of sperm swimming near a wall based on the immersed boundary-lattice Boltzmann method, Engineering Applications of Computational Fluid Mechanics. 2020，14:1,853-870.
Description: The immersion boundary-lattice Boltzmann method was proposed to establish the self-propelled sperm swimming model. Studying the phenomenon of “wall acceleration” by setting the sperm to swim along a planar wall, and revealing the principle of “wall acceleration”.
说明：提出利用浸入边界-格子Boltzmann方法建立精子自驱动游动模型。研究了精子沿壁面游动时获得的“壁面加速”现象，通过分析精子推进机理阐述了精子运动过程中的“壁面加速”原理。
[4] Yuan-Qing Xu, Ming-Yi Wang, Qiong-Yao Liu, Xiao-Ying Tang, Fang-Bao Tian*. External Force-Induced Focus of a Flexible Plate in a Viscous Fluid. Applied Mathematical Modelling 53 (2018) 369–383.
Description: A flexible vibrating plate near a planar wall is studied, finding that the plate tends to approach the wall gradually. If applying an asymmetric vibration force, the plate can keep a fixed distance away from the wall, called the “external-force-induced focusing” phenomenon.Based on the model, the wall attraction effect can be quantified by measuring the asymmetric force.
说明：研究了弹性板在壁面附近振动时出现的“渐进式接近壁面”的现象。通过施加不对称的振动驱动力，发现弹性板可以在距离壁面特定的位置周期振动，称之为振动弹性板的“外力诱导聚焦”现象。通过控制非对称力大小，可以量化壁面吸附力。
[5]Si-Ying Jiang; Jun Yu; Jun Wang; Dong-Fang Li; Yuan-Qing Xu*. A free-swimming tadpole model based on immersed boundary-lattice Boltzmann method and its application[J].Physics of Fluids 35, 081906 (2023)
Abstract：We used the immersed boundary-lattice Boltzmann method (IB-LBM) to establish a two-dimensional autonomous locomotion control bionic tadpole model. The tadpole is established by connecting a passive elliptical head with a beating tail. It can control the tail swing amplitude to change the swimming speed and achieve the desired swimming direction by attaching an angle offset on the tail axis. Based on the proposed tadpole swimming model, we studied its hydrodynamics in the swimming process by changing the confined space’s width. And three points can be summarized as follows. First, in a specific width scope, the same swimming pattern will produce a lower swimming speed in a narrower channel. Second, a slight swing strength causes a small-scale disturbance to the surrounding fluid and will generate a small swimming speed. Third, a relatively small or excessive swimming speed is not conducive to the stability of its swimming. In addition, we further developed a perception-response strategy for the tadpole to achieve its autonomous locomotion control. A virtual perceptive field is proposed as the visual range, which helps to implement tadpole motion control with a set of mechanical response rules. With these improvements, the tadpole can effectively implement obstacle avoidance in complex obstacle array environments and track sine curve routines. Therefore, our study is significant in providing a reference for the theoretical design of some underwater bionic tadpole-like robots.
摘要
我们使用浸入边界-格子玻尔兹曼方法（IB-LBM）建立了一种二维自主运动控制的仿生蝌蚪模型。蝌蚪由一个被动的椭圆形头部和一个摆动的尾巴构成。运动过程中，可以控制尾巴摆动幅度以及在尾轴上附加角度偏移来改变游泳速度和实现预期的游动方向。基于提出的模型，我们通过改变受限空间的宽度来研究蝌蚪在推进过程中的流体动力学。主要有三点结论。一是在特定的宽度范围内，相同的游泳模式将在较窄的通道中产生较低的游泳速度。二轻微的摆动强度对周围的流体产生扰动的规模较小，产生的游动速度也相对较慢。三是相对较小或过快的游动速度不利于其运动的稳定性。此外，我们还进一步研究了蝌蚪的对障碍物的感知与运动响应策略，实现了运动的自主控制。我们提出了一个虚拟感知场作为蝌蚪的视觉感知范围，并设计了一组响应规则来实现蝌蚪的运动控制。有了这些改进，一方面蝌蚪可以在复杂的障碍物阵列环境中有效地实现避障，另一方面也可以实现循迹游动，如实现正弦曲线弯曲路径的循迹游动。总体而言，我们的该项研究可为一些水下仿生蝌蚪机器人的理论设计提供重要参考。