自膨胀高聚物注浆材料在二维裂隙中流动扩散仿真方法研究

为深入研究自膨胀高聚物注浆材料在岩体裂隙中的扩散机制,基于计算流体动力学理论,综合运用现代流场计算方法和移动界面追踪技术,初步建立一种变密度浆液在二维裂隙中流动扩散的仿真分析方法。该方法采用有限体积法离散浆液–水两相流动系统控制方程,用Youngs方法追踪浆液–水两相流体移动界面,用SIMPLE算法迭代求解动量离散方程和压力、速度修正方程,实现对浆液–水两相流动系统的数值求解。通过变密度流体在二维矩形狭槽中自由膨胀算例检验该方法的正确性,在此基础上对自膨胀浆液在二维平板裂隙中的扩散过程进行仿真模拟,结果表明采用该方法能够动态展现流场分布特征,实时反映浆液–水之间的驱替作用,为深入研究膨胀性高聚物注浆材料在裂隙岩体中的扩散机制奠定了基础。

RESEARCH ON SIMULATION METHOD OF EXPANSIBLE POLYMER GROUTING MATERIAL FLOWING AND DIFFUSING IN TWO DIMENSIONAL FRACTURE

To investigate the diffusion mechanism of expansible polymer grouting material in fractured rock mass，a numerical approach for simulating variable density grout diffusion in two-dimensional fracture is developed based on computational fluid dynamics theory，modern fluid field calculation method and moving interface tracking technology. For this method，the numerical solution of the two-phase flow system of polymer and water is attained by using FVM for discreting its governing equations，adopting Youngs method to track the interface of the two phase fluid，and employing SIMPLE algorithm to iteratively solve discretised momentum equations，pressure and velocity correction equation. The validity of the proposed method is proved by the example of variable density fluid freely expanding in the two-dimensional rectangular slot. Then the algorithm is used for simulating the expansible grout?s diffusion in two-dimensional plate fissure，and the results show that the method can dynamically display the distribution characteristics of the flow field and the displacement effect between poymer and water，which can lay a foundation for further research on the expansible polymer grouting material’s diffusion mechanism in fractured rock mass.