...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Computational Physics >Accuracy and stability in incompressible SPH (ISPH) based on the projection method and a new approach
【24h】

Accuracy and stability in incompressible SPH (ISPH) based on the projection method and a new approach

机译：基于投影法和新方法的不可压缩SPH（ISPH）的准确性和稳定性

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The stability and accuracy of three methods which enforce either a divergence-free velocity field, density invariance, or their combination are tested here through the standard Taylor-Green and spin-down vortex problems. While various approaches to incompressible SPH (ISPH) have been proposed in the past decade, the present paper is restricted to the projection method for the pressure and velocity coupling. It is shown that the divergence-free ISPH method cannot maintain stability in certain situations although it is accurate before instability sets in. The density-invariant ISPH method is stable but inaccurate with random-noise like disturbances. The combined ISPH, combining advantages in divergence-free ISPH and density-invariant ISPH, can maintain accuracy and stability although at a higher computational cost. Redistribution of particles on a fixed uniform mesh is also shown to be effective but the attraction of a mesh-free method is lost. A new divergence-free ISPH approach is proposed here which maintains accuracy and stability while remaining mesh free without increasing computational cost by slightly shifting particles away from streamlines, although the necessary interpolation of hydrodynamic characteristics means the formulation ceases to be strictly conservative. This avoids the highly anisotropic particle spacing which eventually triggers instability. Importantly pressure fields are free from spurious oscillations, up to the highest Reynolds numbers tested.
机译：此处，通过标准泰勒-格林和自旋涡旋问题，对强制采用无散度速度场，密度不变性或其组合的三种方法的稳定性和准确性进行了测试。尽管在过去十年中已经提出了各种不可压缩SPH（ISPH）的方法，但本文仅限于压力和速度耦合的投影方法。结果表明，无散度ISPH方法虽然在不稳定之前就可以准确地在某些情况下保持稳定性。不变密度的ISPH方法是稳定的，但是在干扰等随机噪声方面却不准确。组合式ISPH结合了无散度ISPH和密度不变式ISPH的优点，尽管计算成本较高，但可以保持准确性和稳定性。颗粒在固定的均匀网格上的重新分布也被证明是有效的，但是失去了无网格方法的吸引力。此处提出了一种新的无散度ISPH方法，该方法可保持精度和稳定性，同时保持网格自由，而不会通过将粒子从流线稍微移开而增加计算成本，尽管必要的流体动力特性插值意味着该公式不再严格保守。这避免了最终引发不稳定性的高度各向异性的颗粒间距。重要的是，压力场没有杂散振荡，直到测试的最高雷诺数为止。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号