In the numerical studies of active particles, models consisting of a solid body and a fluid body have been well established and widely used. In this work, such an active Brownian particle (ABP) is realized in molecular dynamics (MD) simulations. Immersed in a fluid, each ABP consists of a head particle and a spherical phantom region of fluid where the flagellum of a microswimmer takes effect. Quantitative control over the orientational persistence time is achieved via an external stochastic dynamics. This control makes it possible to validate ABP’s diffusion property in a wide range of particle activity. In molecular description, the axial velocity of ABP exhibits a Gaussian distribution. Its mean value defines the active velocity which increases with the active force linearly, but shows no dependence on the rotational diffusion coefficient. For the active diffusion coefficient measured in free space, it shows semi-quantitative agreement with the analytical result predicted by a...

中文翻译：

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分子动力学模拟的活性布朗粒子

在活性颗粒的数值研究中，由固体和流体组成的模型已经被很好地建立和广泛使用。在这项工作中，这样的活性布朗粒子（ABP）在分子动力学（MD）模拟中得以实现。浸入液体中的每个ABP均由头部颗粒和液体的球形幻影区域组成，微游泳器的鞭毛在其中起作用。定向持久性时间的定量控制是通过外部随机动力学实现的。这种控制使得可以在广泛的颗粒活性范围内验证ABP的扩散性能。在分子描述中，ABP的轴向速度表现出高斯分布。它的平均值定义了有效速度，该速度随有效力线性增加，但与旋转扩散系数无关。