集水廊道附近三維地下水流數值模式率定方法建立與應用－以二峰圳為例

Establishment and Application of 3D Numerical Model Calibration Method for Groundwater Flow Near Infiltration Gallery－ A Case Study of the Er-Feng Canal

劉宏仁(Hung-Jen Liu) ； 徐年盛(Nien-Sheng Hsu) ； 江崇榮(Chong-Rong Jiang) ； 黃建霖(Chien-Lin Huang) ； 鈕希婷(Xi-Ting Niu)

《農業工程學報》 64卷3期 (2018/09) Pp. 63-78

https://doi.org/10.29974/JTAE.201809_64(3).0005

摘要

本研究旨在建立集水廊道附近三維地下水流數值模式率定方法並將其應用於林邊溪二峰圳以彰顯所建立方法之可用性。首先蒐集研究區域之地質鑽探井、河道地質探測及地下水位觀測井之相關資料，建立其水文地質概念模型並由水平衡分析結果了解地下水系統之流入或流出狀況，而後建立三維飽和與未飽和地下水流數值模式以模擬集水廊道附近之地下水流況，同時參考前人研究後提出一合理且誤差在容許範圍內之粗砂未飽和土壤參數曲線之修正曲線，並使數值模式得以收斂。接著建立一套自動化數值模式率定方法進行穩態數值模式率定以獲得透水係數及未飽和土壤參數，最後以率定完成之結果為基礎，進行暫態模式率定以獲得河道流量、河道補注量與蒸發量之長期趨勢。林邊溪二峰圳集水廊道附近地下水流數值模式率定結果顯示，河道沖積層之透水係數K大約介於93~360 m/d，河床質表層透水係數大約介於2.7~8.8 m/d，廊道濾層則為176 m/d，皆在其透水係數之合理範圍內。各觀測井於2010/1/1~2010/9/5旱季與雨季之模擬水位均方根誤差皆小於0.46 m，集水廊道集水量於旱季與雨季之均方根誤差分別為5,746、26,743 cmd，誤差比例小於16%，可合理描述集水廊道取水之水位與水量變化情形。

關鍵字

集水廊道 ； FEMWATER ； 優選模式 ； 二峰圳

並列摘要

The aim of this study is to establish a 3D numerical model calibration method for groundwater flow near infiltration gallery and apply to the Er-Feng Canal of Lin-Bien River to prove the availability of the method. First, this study collects the drilling data, resistivity image profile and observation data near study area, and establishes a hydrogeological conceptual model to realize groundwater inflow and outflow condition by water balance estimation, and then builds a 3D saturated and unsaturated groundwater numerical model to simulate groundwater flow near infiltration gallery. Meanwhile, referring to previous results, this study proposes a reasonable curve of unsaturated soil with small error to revise the hydraulic conductivity of coarse sand, which makes the model converge. After that, this study establishes an auto-optimization model for parameter verification to get the hydraulic conductivity and the parameters of soil water retention curve in steady-state model, and conducts parameter verification to get river recharge and evaporation in long-term trend in transition model. According to the results of calibrated groundwater flow model near infiltration gallery of Er-Feng Canal, the hydraulic conductivity of riverbed alluvial is 93~360 m/d, the river bottom sediment is 2.7~8.8 m/d, the filter layer of infiltration gallery is 176 m/d, all of them are in a reasonable range. Then, root mean square error (RMSE) of simulated groundwater level during dry and rainy season in 2010/01/01~2010/09/05 are less than 0.46 m. The RMSE of water intake at infiltration gallery is 5,746 and 26,743 cmd respectively, with error ratio less than 16%. This shows the success of the proposed model calibration method.

並列關鍵字

Infiltration gallery ； FEMWATER ； Optimization ； Er-Feng Canal