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arXiv 2304.14865physics.flu-dyn
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一种用于弱可压缩 SPH 的高效且通用的一致性修正方法

An efficient and generalized consistency correction method for weakly-compressible SPH

Yaru Ren, Pengzhi Lin, Chi Zhang, Xiangyu Hu

AI总结:

针对弱可压缩 SPH 中 KGC 矩阵求逆导致的不稳定问题,提出加权 KGC 一致性修正并结合 Riemann 压力项与双准则时间步进,在二维和三维自由表面流动中降低耗散、保持压力平滑。

摘要:

本文提出了一种新的高效且通用的弱可压缩光滑粒子流体动力学一致性修正方法,并首次成功应用于具有破碎和冲击事件的剧烈自由表面流动模拟。众所周知,原始核梯度修正(KGC)会因矩阵求逆而产生数值不稳定性。本方法通过引入 KGC 矩阵与单位矩阵的加权平均,而非直接应用 KGC 矩阵,解决了这一问题,从而在实现数值稳定性的同时降低数值耗散。为保证动量守恒,通过重写 Riemann 解的压力项,以粒子平均的形式实施该修正。此外,所提出的加权 KGC 格式被纳入 Zhang 等人(2020)开发的双准则时间步进框架,以获得优化的计算效率。研究考察了一组二维和三维数值算例,结果表明本方法能够显著降低数值耗散,同时对一般自由表面流动呈现平滑的压力场。

英文摘要:

In this paper, a new efficient and generalized consistency correction method for weakly-compressible smoothed particle hydrodynamics is proposed and successfully implemented in the simulation of violent free-surface flow exhibiting breaking and impact events for the first time. It's well known that the original kernel gradient correction (KGC) encounters numerical instability resulting from matrix inversion. The present method remedies this issue by introducing a weighted average of the KGC matrix and the identity matrix, other than directly applying KGC matrix, to achieve numerical stability meanwhile decrease numerical dissipation. To ensure momentum conservation, the correction is implemented in a particle-average pattern by rewriting the the pressure term of the Riemann solution. Furthermore, the proposed weighted KGC scheme is incorporated into the dual-criteria time-stepping framework developed by Zhang et al. (2020) \cite{22} to achieve optimized computational efficiency. A set of numerical examples in both two- and three-dimensions are investigated to demonstrate that the present method can significantly reduce numerical dissipation meanwhile exhibit a smooth pressure field for general free-surface flows.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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