格子Boltzmann方法模拟土体渗流场研究

格子Boltzmann方法模拟土体渗流场,较传统的数值计算方法具有并行计算能力好、能得到流场细节信息、擅长处理复杂边界的独特优势。通过构建入口边界为非平衡外推格式、出口边界为充分发展格式、左右边界为反弹格式的基于通用渗流模型的LBM模型,编程实现格子Boltzmann方法模拟水在同一级配三种颗粒随机分布的土壤中的渗流情况。通过经典算例验证了所编程序的正确性和有效性,并由得到的渗流场图分析发现,土体颗粒的均匀性和通透性较好时渗流场流线的形状和畅通性也较好。

Lattice Boltzmann Method for Simulation Seepage Field of Soil

The lattice Boltzmann method (LBM) is used to simulate fluid flow. Compared to the traditional numerical methods, the LBM has advantages, such as excellent capability of parallel computing, obtaining the details information of flow field and dealing with complex boundary problems easily. In this study, the LBM is used to simulate the fluid flow through three type soils with different particle distributions under same gradation. The boundary conditions of LBM model which constructed are as follow: the non equilibrium extrapolation format on the inlet boundary, the full development format on outlet boundary, the rebound format on both left and right boundary. The constructed model is based on general seepage LBM model. The accuracy and validity of the model is verified by the classical examples. Flow field information from the seepage field diagrams is analyzed. It is found that the better of the homogeneity and permeability of the soil particles is, the better of the shape and the smooth of the seepage field streamline are.