In this paper,we considered quantitatively the well storage effect on the barometric fluctuationinduced water level fluctuation in a well screened in a single confined aquifer.The mathematical model for the system is given,and an analytical solution to the model is derived.The quantitative dependency of the well water level variation on the model parameters such as the well radius,the hydraulic diffusivity of the aquifer,and the barometric fluctuation is discussed.It is found that for a fully-penetrating well in a common confined aqwifer,when the well diameter is greater than 0.1m,the storage of well has significant attenuating and timetag effects on the well water level fluctuations induced by the barometric pressure fluctuations.The well water level fluctuation becomes weak as the well radius increases and/or the aquifer' s hydraulic diffusivity decreases.When the well radius tends to infinity or the hydraulic diffusivity tends to zero,water level in well will no longer fluctuate with barometric fluctuation.On the other hand,when the well radius tends to zero or the hydraulic diffusivity tends to infinity,the water level in well will fluctuate with the barometric fluctuation in an inverse phase (i.e.,phase shift =π),and the ratio of the well water level fluctuation amplitude to the barometric fluctuation amplitude equals the barometric efficiency.%定量研究了井孔储存量对气压波动引起的承压含水层井水水位波动的抑制和滞后效应,建立了相应的数学模型,并推出了其解析解,给出了承压含水层井孔水位波动与气压波动的定量关系.分析发现,对于常见承压含水层完整井来说,当其井径大于0.1m时,井孔储存量对气压波动引起的井水水位波动具有明显的控制和滞后效应.随着井径的增大或者含水层水力扩散系数的减小,气压波动引起的井水水位的波动减弱.当井径无穷大或含水层水力扩散系数无穷小时,井水水位不再随气压波动;反之,当井径无限小或含水层水力扩散系数无穷大时,井水水位则正好以反相位随气压波动,且井水水位波动幅度和气压波动幅度之比刚好为气压效应系数.
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