基于CFD-DEM耦合的尾矿库溃坝数值模拟

Numerical Simulation of Tailings Pond Dam Break Based on CFD-DEM Method

流体在尾矿库溃坝的形成和发展过程中起到至关重要的作用,开展尾矿坝流固耦合研究对认识尾矿库溃坝形成机理和演化规律具有重要意义。选取某典型尾矿库溃坝工程实例,采用CFD-DEM流固耦合方法,先通过标定试验确定数值模拟细观参数,再对尾矿库溃坝过程进行数值模拟,获得溃坝过程中坝体和尾矿砂的位移场和速度场,并计算尾矿砂运移距离,计算结果与事故调查报告相吻合,证明CFD-DEM流固耦合方法在尾矿库溃坝数值模拟的可行性。数值模拟结果表明:溃坝形成初期,滑移面后方有一个受挤压的区域,滑移面进口端深且陡,出口端较为平缓;尾矿坝溃坝后形成的堆积体呈两头密中间疏,在浆砌子坝前方形成明显的分割带。

Fluid plays a crucial role in the formation and development of tailings pond dam break.The study of fluid-soild coupling of tailings dam is of great significance to understand the formation mechanism and evolution law of tailings pond dam break.The CFD-DEM fluid-soild coupled method is adopted to simulate a typical dam-break project of tailings pond.Numerical simulation of microstructure parameters are determined by calibration experiments,and then are used to numerically simulate the process of the tailings dam.The displacement field and velocity field of dam body and tailing sand in the process of dam break can be obtained,and the migration distance of tailing sand is calculated.The calculated results are consistent with the accident investigation report,which proves the feasibility of CFD-DEM coupled method in the numerical simulation of tailings dam break.The numerical simulation result shows that at the early stage of dam break,there is a compressed area behind the slip surface,and the inlet end of the slip surface is deep and steep,while the outlet end is gentle.The accumulation body formed after the tailings dam break is dense at both ends while sparse in the middle,and an obvious partition zone is formed in front of the slurry sub-dam.