一种考虑流体状态方程的土体CFD-DEM耦合数值方法

蒋明镜; 张望城

doi:10.11779/CJGE201405001

一种考虑流体状态方程的土体CFD-DEM耦合数值方法 English Version

蒋明镜^{1, 2},
张望城^{1, 3}

1. 同济大学土木学院地下建筑与工程系,上海 200092; 2. 岩土及地下工程教育部重点实验室（同济大学）,上海 200092; 3. 西澳大利亚大学海洋基础系统中心,澳大利亚珀斯 WA6009

基金项目: 国家杰出青年科学基金项目（51025932）; 教育部博士点基金项目（20100072110048）

详细信息

作者简介:
蒋明镜(1965- ),男,教授,博士生导师,“同济大学特聘教授”,主要从事天然结构性黏土、砂土、非饱和土、太空土和深海能源土宏观微观试验、本构模型和数值分析研究。E-mail: mingjing.jiang@tongji.edu.cn。

中图分类号: TU411
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出版历程
- 收稿日期: 2013-07-22
- 发布日期: 2014-05-20

Coupled CFD-DEM method for soils incorporating equation of state for liquid

JIANG Ming-jing^{1, 2},
ZHANG Wang-cheng^{1, 3}

1. Department of Geotechnical Engineering, College of Civil Engineering, Tongji University, Shanghai 200092, China; 2. Key Laboratory of Geotechnical & Underground Engineering, Ministry of Education, Shanghai 200092, China; 3. Centre for Offshore Foundation Systems, University of Western Australia, Perth WA6009, Australia

摘要

摘要: 在离散元（DEM）商业软件PFC^2D的基础上,通过将描述流体体变-压力非线性关系的Tait状态方程（EOS）引入计算流体动力学（CFD）,建立模拟弱可压缩流体的CFD-DEM耦合计算模块。首先,推导CFD-DEM的控制方程：包括流体-颗粒相互作用力方程、流体运动方程、Tait状态方程和颗粒运动方程。接着,通过PFC^2D自定义FISH语言和C++语言将离散化的CFD-DEM控制方程嵌入商业软件PFC^2D中。最后,通过单颗粒水下自由沉降运动和一维单面排水固结试验的模拟验证该耦合模块的可行性。模拟结果表明单颗粒自由沉降速度和Stokes理论解接近,一维单面排水固结试验中孔压消散和固结度随着无因次时间因数T_v的变化均与太沙基固结理论符合较好。从而使得用离散元法全耦合分析土体不排水条件下的力学特性成为可能。
- CFD-DEM数值方法 /
- Tait状态方程 /
- 颗粒自由沉降 /
- 一维单面排水固结
Abstract: The Tait equation of state for liquid is implemented into the N-S equations-based computational fluid dynamics (CFD). This method is then coupled with the distinct element method (DEM) so as to establish CFD-DEM codes to simulate the porous media with weakly compressive fluid. Firstly, the governing equations for the coupled CFD-DEM method are introduced, including equations for fluid-particle interaction forces, N-S equations, Tait equation of state for liquid and motion equations for particle system. Then, a coupled CFD-DEM scheme is implemented into the DEM commercial software PFC^2D. Finally, two benchmarking examples, namely, single particle free settling and one-dimensional consolidation, are used to validate the coupled CFD-DEM method. The results show that in the CFD-DEM simulations the free settling velocity of single particle meets the Stokes's solution, and the excess pore pressure and degree of consolidation at different values of T_v are close to those of the Terzaghi's consolidation theory.
- coupled CFD-DEM method /
- Tait equation of state /
- single particle free settling /
- one-dimensional consolidation

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参考文献(19)

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