封洞库低渗介质地下水渗流场数值模型的参数反演

Parameter Inversion Study of Low Permeability Media Seepage Numerical Model for Groundwater-sealed Cavern

在地下水数值模拟工作中,模型参数是影响数值模型计算准确度的关键因素。对于低渗裂隙介质场,传统的参数分区方法很难准确地刻画低渗裂隙介质场的非均质性,因此需要利用有效的方法优化数值模型参数,使其计算结果更加准确、可靠。建立了烟台某地下水封洞库的低渗介质地下水渗流场数值模型,并对模型中的关键参数--岩体渗透系数进行了参数反演,得到了模型中两个关键层位的岩体渗透系数场。结果表明:研究区岩体渗透系数表现出强烈的非均质性,丁烷洞库在-94^-100m深度上形成了强渗透带,造成丁烷洞库地下水涌水量偏大。参数优化后的数值模型的计算精度进一步提高,能够准确地刻画地下水封洞库的运行状态。

In the groundwater numerical simulation work,the model parameters are the key factors affecting the accuracy of numerical simulation.The traditional parameter partitioning method can hardly describe the anisotropism of low permeability fracture medium field,so an effective parameter optimizing method is expected to increase the veracity of the numerical model.This paper establishes a seepage model of a groundwater-sealed cavern in Yantai City,and optimizes the permeability coefficients of two crucial layers by the parameter inversion method.The results indicate that the permeability coefficient of rock mass is strongly anisotropic in the study area,and a high permeability zone exists in -94^-100 m depth of Butane cavern,which makes the water inflow of Butane cavern more than that of others.After the parameter optimization analysis,the seepage model is more accurate which can describe the operational condition of the groundwater-sealed cavern precisely.