考虑低速非达西的第一类越流系统中承压完整井稳定流模型

Research on non-Darcian steady flow to a well fully penetrating a confined aquifer in the first kind of leaky aquifer system

基于忽略非线性段的存在启动压力梯度的非达西数学模型,采用数值差分法求解第一类越流系统中承压完整井非达西稳定流方程,并分析了抽水量、导水系数、越流系数及启动压力梯度对达西与非达西条件下的承压水头分布差异的影响。结果表明:考虑非达西流情况后,随距抽水井距离的增大,达西、非达西条件下的水头分布差异先增大后减小,在无穷远处趋于零。距抽水井较近时,抽水量、导水系数、越流系数及启动压力梯度对两种条件下的水头分布差异影响不大。随着远离抽水井,抽水量、导水系数及启动压力梯度越大或越流系数越小,两种条件下的水头分布差异越大。随着距离进一步增大,差异逐渐减小并趋于零。

Based on the starting pressure gradient existence of non-Darcy flow in low permeability porous media,the mathematical model of non-Darcian steady flow to a well fully penetrating a confined aquifer in the first kind of leaky aquifer system is established. And confined groundwater head is obtained by numerically solving the equation of groundwater flow. The effects of pumpage, confined aquifer coefficient of transmissibility,the leakance and starting pressure gradient of aquitard on the head difference of confined groundwater between Darcy flow and non-Darcy flow are analyzed. The results show that the head difference of confined groundwater between Darcy flow and non-Darcy flow increases first and then decreases with the increase of distance from the pumping well and is coming to zero in the infinite domain. All of these factors have little influence on the head difference of confined groundwater between Darcy flow and non-Darcy flow near the pumping well. With the increase of the distance from the pumping well,all factors except the leakance of aquitard have significant positive correlation to the head difference of confined groundwater between Darcy flow and non-Darcy flow. And this head difference is coming to zero in the infinite domain.