A method for estimating the interactions in dissipative particle dynamics from particle trajectories
A method for estimating the interactions in dissipative particle dynamics from particle trajectories
复制标题
一种从粒子轨迹估计耗散粒子动力学中相互作用的方法
DOI：
10.1088/0953-8984/21/9/095401
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发表时间：
2008
期刊：
影响因子：
--
通讯作者：
K. Tunstrøm
中科院分区：
文献类型：
--
作者：
Anders Eriksson;M. N. Jacobi;J. Nyström;K. Tunstrøm
介绍了一种由相空间投影轨迹确定耗散粒子动力学(DPD)模型中随机相互作用和耗散相互作用的泛函形式的方法。DPD模型被视为详细动力学的粗粒化，显示出清晰的时间尺度分离。基于Mori-Zwanzig投影算符方法，我们导出了DPD中随机相互作用的相容方程。一致性方程可以通过迭代自举过程来求解。结合保守相互作用估计的标准技术，我们的方法使重建粗粒度DPD模型中的所有力成为可能。我们通过从相空间轨迹重建DPD模型中的相互作用来演示该方法是如何工作的。此外，我们还讨论了我们的方法如何应用于具有有限时间尺度分离的实际系统。
We introduce a method for determining the functional form of the stochastic and dissipative interactions in a dissipative particle dynamics (DPD) model from projected phase space trajectories. The DPD model is viewed as a coarse graining of a detailed dynamics that displays a clear timescale separation. Based on the Mori–Zwanzig projection operator method we derive a consistency equation for the stochastic interaction in DPD. The consistency equation can be solved by an iterative bootstrapping procedure. Combined with standard techniques for estimating the conservative interaction, our method makes it possible to reconstruct all the forces in a coarse-grained DPD model. We demonstrate how the method works by recreating the interactions in a DPD model from its phase space trajectory. Furthermore, we discuss how our method can be used in realistic systems with finite timescale separation.