徐州市张集水源地裂隙岩溶水三维等参有限元数值模拟

An isoparametric finite element 3-D numerical model for the fracture-karst flow in a wells field

基于徐州市张集水源地裂隙岩溶水贮存和运动特征,建立了三维有限元数学模型,利用等参有限元方法求解,并根据大型群孔干扰抽水试验资料,识别模型参数,进一步对裂隙岩溶水资源的开采方案进行了评价,得到结论如下:(1)模型具有较高的精度,适合于张集水源地裂隙岩溶水资源评价;(2)张集水源地的允许开采量为13 71万m3 d,这一数值是有保证的;(3)在年降水量大于846 4mm(该区历史上降水量偏低的10年的年平均降水量)的年份,允许开采量可增大。上述结论为水源地开采提供了依据,同时对条件类似地区的地下水资源评价具有重要的参考价值。

The authors developed a 3D finiteelement numerical model to simulate the fracturekarst water flow in a wells field located at Zhangji of Xuzhou City.The isoparametric finite element technique was adopted.Parameters of the model were identified with the data obtained from the pumping test.Some exploitation schemes on fracturekarst water resources were evaluated with the model computation.The results showed that:the model was fit for the evaluation of groundwater resources in the Zhangji wells field and the alike;the allowable pumping volume for Zhangji well field was 137,100m3/d;the allowable pumping volume may be increased when the annual precipitation exceeds 8464mm(the average value of the lowest 10 years' annual precipitation).The analysis above can be taken as a basis for Zhangji wells field exploitation as well as a reference for similar water resources areas.