arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1110.5752physics.flu-dynphysics.comp-ph
收藏

光滑粒子流体动力学方法中不可压缩性约束的分析

Analysis of the incompressibility constraint in the Smoothed Particle Hydrodynamics method

Kamil Szewc, Jacek Pozorski, Jean-Pierre Minier

摘要:

光滑粒子流体动力学是一种基于粒子的、完全拉格朗日的流体流动模拟方法。在这项工作中,该方法的基本概念首先简要回顾。然后,我们提出了一个彻底的比较三种不同的不可压缩性处理SPH:弱可压缩的方法,其中使用一个适当选择的状态方程;和两个真正的不可压缩的方法,其中的速度场投影到一个无发散空间进行。一个值得注意的方面的研究是,在每一个不可压缩性处理,相同的边界条件被使用(并进一步发展),这使得直接比较。与实施相关的问题也进行了讨论,并提出和验证了计算参数的最佳选择。数值结果表明,目前最先进的真正不可压缩的方法(基于速度校正)遭受的密度累积误差。为了解决这个问题,一个算法,基于粒子的速度和位置的校正,提出。本文的最后一部分对这种密度校正的有效性进行了检验和论证。

英文摘要:

Smoothed particle hydrodynamics is a particle-based, fully Lagrangian, method for fluid-flow simulations. In this work, fundamental concepts of the method are first briefly recalled. Then, we present a thorough comparison of three different incompressibility treatments in SPH: the weakly compressible approach, where a suitably-chosen equation of state is used; and two truly incompressible methods, where the velocity field projection onto a divergence-free space is performed. A noteworthy aspect of the study is that, in each incompressibility treatment, the same boundary conditions are used (and further developed) which allows a direct comparison to be made. Problems associated with implementation are also discussed and an optimal choice of the computational parameters has been proposed and verified. Numerical results show that the present state-of-the-art truly incompressible method (based on a velocity correction) suffer from density accumulation errors. To address this issue, an algorithm, based on a correction for both particle velocities and positions, is presented. The usefulness of this density correction is examined and demonstrated in the last part of the paper.

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。

↑