本研究的主要目的是發展水錐數值模式，研究在油水兩相地層中水錐形成之現象，預測水錐自油水界面抵達穿孔底部的貫穿時間以及研究在不出水之最大產率(臨界產率)。此外，也研究在關井後水錐消退之現象。
本研究建立在油水兩相地層部分穿孔井數值模式，以進行水錐貫穿、水錐消退與臨界產率之研究。藉由數值模擬之結果，可得無因次水錐貫穿時間(tBT)D隨無因次產率(qD)變化之關係式為(tBT)D=9.34*10^-8*qD^-12.36。根據這個關係式可得，當無因次水錐貫穿時間趨近於無窮大時，無因次產率(或無因次臨界產率)為qcD=0.13，由該無因次臨界產率可計算現地之臨界產率。本研究也利用數值模擬所得之結果顯示，當水錐接近穿孔區間底部時，則將生產井關井以研究水錐之消退，模擬結果顯示無因次水錐消退時間會隨著無因次產率的漸少而增加。
將模擬所得之臨界產率與文獻中解析解結果相互比較，顯示模擬結果高於文獻中之解析解之結果。在水錐貫穿時間方面，其模擬結果與Hagoort模式較接近；Sobocinski and Cornelius 模式所得之貫穿將較本文長，而Bournzal and Jeanson模式所得結果則較短。

The purposes of this study are to develop a numerical model to study water coning in an oil-water reservoir, to predict the water coning breakthrough from oil-water contact (OWC) in a production well and to estimate the critical oil production rate. The critical oil production rate is the maximum oil production rate with no water produced. This study is also to investigate the phenomena of water coning decline after producing well is shutting in.
A numerical model with a partial-penetration-oil-producing well in an oil-water reservoir is developed for studying the water coning breakthrough, water coning decline and critical production rate.
Based on the results of numerical study, the relationship between the dimensionless water coning breakthrough time (tBT)D and the dimensionless production rate (qD) can be expressed as (tBT)D=9.34*10^-8*qD^-12.36 . By using this equation, the dimensionless critical rate is 0.13 for the being approached to infinite. For the production well is shutting-in when the water coning approaches to the bottom of the perforation internal, the results show that the dimensionless water coning decline time is increasing as the dimensionless production rate decreasing.
In comparing the critical rates, the results from simulation are slightly higher then these from analytical solutions existed in literature. The water coning breakthrough time from simulation is close to Hagoort’s model; and the result from numerical model is lower than it from Sobocinski and Cornelius’ model, but higher than it from Bournzal and Jeanson’s model .

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