本研究的主要目的是利用數值模擬法，建立油水兩相數值模式，研究水平井生產所造成之水錐形成速度與生產率的關係，而計算臨界產率並建立水錐貫穿時間典型曲線。其中，研究不同的水平孔段高度、水平孔段長度、地層毛細壓力、地質異向性對臨界產率的影響。本研究使用CMG公司的IMEX數值模擬軟體建立數值模式。

由模擬研究可以得到不同生產率之水錐上升高度隨時間變化曲線，而推求水錐貫穿時間。經過無因次轉換，繪製而得無因次水錐貫穿時間隨無因次生產率變化之典型曲線，利用該典型曲線的趨勢可推求臨界產率。地層參數(毛細壓力及地層異向性)及完井條件(水平孔段高度及水平孔段長度)對於臨界產率及水錐貫穿時間之影響如下：(1)毛細壓力地層的臨界產率較無毛細壓力地層的臨界產率為低；(2)水平孔段高度(水平鑽井的位置)越高，水錐到達井底的距離較長，出水的時間較慢，其臨界產率越高；(3)水平孔段長度越長，水錐貫穿時間越長，臨界產率越高；(4)在地質異向性方面，垂直/水平滲透率比越小，其臨界產率越高；(5)在相同地層條件下，垂直井之臨界產率較水平井之臨界產率為低。

The purpose of this study is to develop a water conning numerical model of a horizontal well for studying the relationship between the conning breakthrough time and the production rate, and for estimating the critical production rate. The effects of well location, length of the horizontal section, capillary pressure, and formation anisotropy on the critical production rate are considered in the model. A black-oil model simulator, IMEX from CMG, is used in this study to simulate the behavior of water conning of horizontal well.

The results of the relationship of the coning breakthrough time and the production rate from simulation study are used to establish the coning breakthrough time type curves. These type curves can be used to estimate the critical production rate of horizontal well. The results of this study show that: (1) The critical production rate for a formation with capillary pressure is smaller than that without capillary pressure; (2) The higher critical production rate will be obtained the higher well location; (3) The higher critical production rate will be higher for the longer horizontal section; (4) In the case of anisotropic formation, critical production rate will be higher for the smaller ratio of vertical/horizontal permeability; (5) The critical production rate for a horizontal well is higher than that of a vertical well; thus, the producitivity of a horizontal well is better than that of a vertical well.

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