论文标题
极性活性流体的热力学一致的粗粒
Thermodynamically consistent coarse-graining of polar active fluids
论文作者
论文摘要
我们引入了一种闭合模型，用于极性活性流体的粗粒度动力学理论。基于粒子分布函数的准平衡近似，该模型紧密捕获了动力学理论的重要分析特性，包括其线性稳定性以及熵产生和耗散的平衡。非线性模拟显示该模型再现了动力学理论的定性行为和非平衡统计数据，这与常用的闭合模型不同。我们使用闭合模型在两个和三个维度中模拟高度湍流的悬浮液，在这些悬浮液中，我们观察到复杂的多尺度动力学，包括较大的浓度波动以及极性和列不足的缺陷。
We introduce a closure model for coarse-grained kinetic theories of polar active fluids. Based on a quasi-equilibrium approximation of the particle distribution function, the model closely captures important analytical properties of the kinetic theory, including its linear stability and the balance of entropy production and dissipation. Nonlinear simulations show the model reproduces the qualitative behavior and nonequilibrium statistics of the kinetic theory, unlike commonly used closure models. We use the closure model to simulate highly turbulent suspensions in both two and three dimensions in which we observe complex multiscale dynamics, including large concentration fluctuations and a proliferation of polar and nematic defects.
