临清市地下水漏斗区含水层补给的数值模拟研究

The Numerical Simulation Study on Aquifer Recharge in the Groundwater Funnel Area in Linqing City, Shandong Province

摘要: 黄泛平原区引黄灌区末端采用井渠结合灌溉方式，引黄时间和量均受到上游限制，且该区浅层地下水超采严重。本文在工程技术上探讨如何在有限的引黄时间内，加大地下水的补给量，缓解地下水位长期下降的趋势。基于Hydrus-2D模型对临清市地下水漏斗区实施的明沟–地下滤水管–竖井含水层补给系统分别进行了明沟补给和地下滤水管补给两种情景下的数值模拟，实际工程和数值模拟中引水时间均为7天。模拟结果表明：整个模拟期内，情景一中明沟底部的地下水位上升了约13 m；情景二中滤水管底部水位抬升了8.5 m，两根滤水管之间的地下水位抬升了2.3 m；地下滤水管的布置有效的增加了地下水的补给量，至模拟期末，明沟的7天的入渗量为18,026 m³，滤水管7天的入渗量为56,224 m³，3根滤水管的入渗量占总入渗量的75.7%，与实际工程中监测的入渗量基本相符。因此该系统对漏斗区的地下水补给能起到良好的作用。
>Well-canal combined irrigation mode is adopted in the lower reaches of irrigated area in the Yellow River flood plain. The diversion time and volume are limited by the upper reaches. In addition, the shallow groundwater overdraft is serious in this area. In this study, based on the engineering technology, how to increase the recharge volume of groundwater in the limited diversion time to ease the long-term downward trend of water table was discussed. The numerical simulation was carried out to the open canal-underground perforated pipe-shaft system which was implemented in the groundwater funnel area in Linqing city based on Hydrus-2D model in two scenarios: the open canal and underground perforated pipe respectively; the diversion time was 7 days in the actual engineering operation and numerical simulation. The simulation results show that: during the whole simulation period, the level which is under the open canal rose 13 m in scenario one; the level which is under the perforated pipe rose 8.5 m and the level between two pipes rose 2.3 m in scenario two. In the meantime, the perforated pipe can efficiently increase the recharge volume of underground water. To the end of the simulation, the recharge volume of the open canal was 18,026 m³, and that of three perforated pipes was 56,224 m³ which was 75.7% of the total recharge volume. The result was basically accorded with the actual monitoring value. Therefore the system plays a good role in recharging underground water in the groundwater funnel area.