论文标题
部分可观测时空混沌系统的无模型预测
A particle-based method using the mesh-constrained discrete point approach for two-dimensional Stokes flows
论文作者
论文摘要
无网状方法固有地不需要网格拓扑,并且实际上用于求解连续方程。但是,这些方法通常往往比常规网格的方法具有更高的计算负载,因为用于空间离散化的计算模具变大。在这项研究中,提出了一种在无网格方法中使用紧凑型模板的新方法,称为网格约束的离散点(MCD)方法。 MCD方法将笛卡尔网格系统引入域的背景。该方法严格地通过通过非线性约束解决动态问题来严格地约束每个网格中离散点(DPS)的分布。这可以避免在网格大小水平上DP分布的异质性,并以固定的自由度进行衍生化评估,并施加紧凑的模具。本文提出了针对DPS安排的基本表述和对不稳定的Stokes Flow的应用。进行了数值测试,以在同轴和偏心圆通道中的DPS分布和流量问题。拟议的MCD方法实现了DPS在空间分辨率方面的合理分布,并在预处理中进行了一些迭代。此外,使用Stokes流量问题中获得的DP分布的解决方案与理论和参考解决方案非常吻合。结果还证实,即使使用紧凑的模板,速度和压力的数值精度也达到了预期的收敛顺序。
Meshless methods inherently do not require mesh topologies and are practically used for solving continuum equations. However, these methods generally tend to have a higher computational load than conventional mesh-based methods because calculation stencils for spatial discretization become large. In this study, a novel approach for the use of compact stencils in meshless methods is proposed, called the mesh-constrained discrete point (MCD) approach. The MCD approach introduces a Cartesian mesh system to the background of a domain. And the approach rigorously constrains the distribution of discrete points (DPs) in each mesh by solving a dynamic problem with nonlinear constraints. This can avoid the heterogeneity of the DP distribution at the mesh-size level and impose compact stencils with a fixed degree of freedom for derivative evaluations. A fundamental formulation for arrangements of DPs and an application to unsteady Stokes flows are presented in this paper. Numerical tests were performed for the distribution of DPs and flow problems in co-axial and eccentric circular channels. The proposed MCD approach achieved a reasonable distribution of DPs independently of the spatial resolution with a few iterations in pre-processing. Additionally, solutions using the obtained DP distributions in Stokes flow problems were in good agreement with theoretical and reference solutions. The results also confirmed that the numerical accuracies of velocity and pressure achieved the expected convergence order, even when compact stencils were used.