安塬水源地地下水流三维数值模拟

Anyuan Water Head Site Groundwater Flow 3D Numerical Simulation

安塬水源地为干河冲洪积扇型水源地,含水层由第四系冲洪积层构成,厚15～30m,非均质,各向同性。受含水层底板坡降的影响,潜水面坡降较大,为5%～8%。三维流特征明显,尤其是抽水试验时在抽水井周边区域不同深度的水头差别更为显著。为了观测不同深度的水位,在群孔抽水试验时在同一观测孔中按上、中、下不同深度设置了3组观测管分别进行水位观测,从而为三维数值模拟提供了水位数据,并以该资料为依据建立了三维有限差分模型,对6种开采方案进行了数值模拟计算和预报。通过11a的开采,证明建立的三维有限差分模型可靠,为水源地的地下水开采建立了较为可靠的数学预报模型。

The Anyuan water head site is situated on an alluvial-pluvial fan of a dry river, the aquifer is Quaternary alluvial-pluvial heterogeneous isotropie deposit with thickness of 15-30m. Impact from the gradient of aquifer floor, thus the gradient of phreatic water table is rather large （5%-8%）. Three-dimensional flow characteristic is obvious; especially head difference of different depths in pumping well peripheral area is more significant during the pumping test. In order to observe the water level at different depths, during the group wells pumping test, in an identical observation well, according to depths of upper, middle and lower, 3 groups of observation pipe have been set up to canT out water table observation and provide 3D numerical simulation with water level data, based on the data 3D finite difference model established, and carry out numerical simulation computation and prediction for 6 exploitation schemes. Through 11 years exploitation has demonstrated that the 3D finite difference model is reliable, thus a rather reliable mathematical prediction model for water head site groundwater exploitation established.