基于裂隙连续方法的三维裂隙岩体渗流传热数值模拟  

Simulation of seepage and heat transfer in 3D fractured rock mass based on fracture continuum method

作　　者：刘东东 魏立新 徐国元[1] 项彦勇[3] LIU Dong-dong;WEI Li-xin;XU Guo-yuan;XIANG Yan-yong(School of Civil Engineering and Transportation,South China University of Technology,Guangzhou,Guangdong 510641,China;Guangzhou Municipal Engineering Design and Research Institute Co.Ltd.,Guangzhou,Guangdong 510600,China;School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China)

机构地区：[1]华南理工大学土木与交通学院,广东广州510641 [2]广州市市政工程设计研究总院有限公司,广东广州510600 [3]北京交通大学土木建筑工程学院,北京100044

出　　处：《岩土力学》2023年第7期2143-2150,共8页Rock and Soil Mechanics

摘　　要：模拟裂隙岩体渗流传热的主要困难在于岩体各种尺度上的非均质性。为了兼顾裂隙岩体渗流传热过程模拟的效率和精度,将二维裂隙连续方法拓展到三维问题中,应用深度优先搜索算法挑出对网格块渗透性有贡献的有效裂隙,综合考虑有效裂隙和岩石基质作用给出网格块的等效渗透率张量,采用Matlab对COMSOL Multiphysics有限元软件进行二次开发,生成由不同渗透率网格块组成的三维裂隙连续模型。数值模拟结果表明:裂隙连续模型结合了随机连续介质模型和离散裂隙模型的特点,既能避免处理裂隙网络的复杂性,又能考虑岩体渗透率的空间变异性,兼顾了模拟效率和精度;当岩石基质渗透率与裂隙渗透率比值的数量级在10-4~10-6范围内时,有效裂隙网络模型的流量计算误差会超过5%。The main challenge of simulating the processes of seepage and heat transfer in fractured rock mass is the heterogeneity of rock mass at various scales.In order to balance the efficiency and accuracy of numerical simulation,the two-dimensional fracture continuum method is extended to a three-dimensional one.Based on the depth-first search algorithm,the effective fractures contributing to the permeability of rock blocks are collected.The block permeability tensor is obtained by considering the contribution of effective fractures and rock matrix.The finite element software COMSOL Multiphysics is integrated with Matlab to generate a three-dimensional fracture continum model that contains multiple blocks with various permeabilities.The simulation results show that due to the combination between stochastic continuum model and discrete fracture model,the fracture continuum model can avoid the complexity of addressing fracture networks and consider the spatial variability of rock mass permeability,thus both the simulation efficiency and accuracy are balanced.As the order of magnitude for the ratio of rock matrix permeability to fracture permeability ranges from 10-4 to 10-6,the discharge calculation error of the effective fracture network model exceeds 5%.

关 键 词：三维裂隙岩体 渗流 传热 深度优先搜索 裂隙连续方法 

分 类 号：D357[政治法律—政治学]