文摘
Delayed yield phenomenon (DYP) occurs when the drawdown of an aquitard is no longer in equilibrium owing to previous changes in the level of water in adjacent aquifers. In this study, an analytical solution to determine the distribution of the drawdown at any time and at any point in an aquitard, in which the water level was not in equilibrium at the initial time, and the water level of the aquifers immediately above and below the aquitard was time dependent was developed. The analytical solution for the flow rate at any time and location was presented based on variations in drawdown in the aquitard. In addition, the effects of the DYP on the leakage rate and depletion of the aquitard were studied. Subsequent comparison of the proposed analytical and numerical solutions revealed that they were in good agreement. The results of this study will be useful to future studies of groundwater flow and environmental problems, such as water budgets, rising sea levels, solute transport, heat conduction and ground subsidence.