Development of multiphase models and its high-performance computing on transportations of solid objects in free-surface flows

自由表面流中固体物体输运的多相模型及其高性能计算的发展

• 批准号: 17560457
• 负责人: USHIJIMA Satoru
• 金额: $ 2.24万
• 依托单位: Kyoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-17560457/
• 关键词: air-water interface; multi-phase model; higher-order scheme; high-speed computation; parallel computation; multiphase flow; rigid body movement; solid-body collision; 二流体モデル; 領域分割

It is important to understand the behaviors of large-scale solid objects transported in free-surface flows, such as debris and floating objects in flood flows and tsunamis. In this study, in order to develop a numerical method to evaluate such multiphase phenomena, three-dimensional computational method, 3D MICS, has been proposed and its validity was examined through the experimental results.In 2005, an experimental tank, which has a wave generator, was set up to understand basic phenomena. In addition, a multiphase-flow solver, MICS, was improved to 3D. The results are summarized as follows:(1)In the created experimental tank, fluid motions entering into dry-areas and fixed solid objects were measured.(2)The movements of solid spheres transported by free-surface flows were captured.(3)The multiphase-flow solver MICS was improved to three-dimensional method and it was applied to the above experimental results. As a result, the validity of the computational method was confirmed.In 2006, the computational method, 3D MICS, was improved to the method that can deal with the non-spherical objects. Its validity was examined with experimental results. The results are summarized as follows:(1)3D MICS was improved to the method that can deal with the non-spherical objects by treating the objects as a collection of tetrahedron elements. The collisions among the solid models are treated with contact sphere. The solid model proposed in this study is called T-type model.(2)Tetrahedron sub-cell method was proposed to evaluate the fraction of tetrahedron elements included in a fluid-computation cell.(3) In order to confirm the validity of the proposed computational method, it was applied to some experimental results, such as floating objects in wave motions, transportation of non-spherical objects and falling objects in water. As a result, the validity of the computational method was confirmed.

了解大尺度固体物体在自由表面流中的运动特性是非常重要的，如洪水和海啸中的碎片和漂浮物。本研究中，为了开发评价这种多相现象的数值方法，提出了三维计算方法3D MICS，并通过实验结果验证了其有效性。2005年，为了了解基本现象，建立了具有波发生器的实验水池。此外，一个多相流求解器，MICS，被改进到3D。主要研究结果如下：（1）在所建立的实验水池中，测量了进入干燥区和固定固体物体的流体运动。（2）捕捉了自由表面流中固体球的运动。（3）将多相流求解器MICS改进为三维方法，并将其应用于上述实验结果。2006年，3D MICS计算方法被改进为可以处理非球形物体的方法。实验结果验证了该方法的有效性。主要研究成果如下：（1）改进了三维MICS方法，将非球形物体视为四面体单元的集合来处理。实体模型之间的碰撞采用接触球处理。本研究中提出的实体模型称为T型模型。（2）提出了计算流体计算单元中四面体单元所占比例的四面体子单元法。(3)为了验证所提出的计算方法的有效性，它被应用到一些实验结果，如浮动物体在波浪运动，非球形物体的运输和水中的下落物体。计算结果验证了该方法的有效性。

项目成果

OpenMPによる並列プログラミングと数値計算法

使用OpenMP的并行编程和数值计算方法

• 发表时间: 2006
• 作者: 藤岡 奨;牛島 省;牛島 省
• 通讯作者: 牛島 省

分散メモリ計算機における局所非定常モデルを用いた楕円型格子生成法

分布式存储计算机中局部非定常模型的椭圆网格生成方法

• 发表时间: 2005
• 期刊: 応用力学論文集 vol.8
• 作者: 牛島 省;藤田 学;禰津 家久
• 通讯作者: 禰津 家久

Numerical prediction method for arbitrarily-shaped bodies moving in three-dimensional fluids

三维流体中任意形状物体运动的数值预测方法

• 发表时间: 2007
• 期刊: Annual Journal of Hydraulic Eng., ASCE vol.51
• 作者: S.Ushijima;A.Fukutani;S.Fujioka;I.Nezu
• 通讯作者: I.Nezu

3D numerical prediction for flood flows into residential area with tetrahedron sub-cell method

四面体子单元法住宅区洪水三维数值预报

• 发表时间: 2007
• 期刊: nual Journal of Hydraulic Eng., ASCE vol.51
• 作者: S.Ushijima;O.Makino;I.Nezu
• 通讯作者: I.Nezu

水路を遡上する波動流れと物体輸送に対する3次元多相場の数値解法(3D MICS)の適用性

3D 多相场数值方法 (3D MICS) 在水道上游波浪流和物体输送中的适用性

• 发表时间: 2006
• 期刊: 応用力学論文集 9
• 作者: 牛島 省;牧野 統師;禰津 家久
• 通讯作者: 禰津 家久