底水油藏水平井水脊形态及上升规律研究

Water Crest Shape and Its Raising Rules in the Reservoirs with Bottom Water

底水油藏中水平井水脊上升规律的研究对合理控制底水脊进、提高无水采油量及生产后期采取合理控水堵水措施具有积极的意义。对水平井跟趾端压降与其产量的关系进行分析,认为在油田实际产量下水平井跟趾端压降极小。采用渗流力学映射反映和势叠加原理建立了底水油藏水脊上升数学模型,并证明了在常规生产参数下的均质底水油藏中,水平井各段等流量分布时的水脊突破位置应位于水平井中段;不等流量分布模式下水脊突破位置在水平井中段左右。采用程序刻画了水脊上升形态,并用三维可视化物理模拟验证了模型的合理性。

The research of water crest raising rules was significant of rational controlling of rapid cresting of bottom water and improving oil recovery in water free production period and as well as rational water controlling and water blocking in the late period of production.The relationship between the pressure drawdown and production output on the toe and heel horizontal wells was analyzed,it was considered that the pressure drawdown on the toe and heel horizontal wells was less in actual production of oilfields.Seepage mechanical mapping reflection and the potential superposition principle were used to establish a mathematical model for water crest raising of bottom water reservoirs.The potential superposition derivation shows that the crest breakthrough is in the middle of the horizontal wellbore in homogeneous bottom water reservoirs under the condition of conventional production data.Computer process demonstrates that the breakthrough point is around middle section of the horizontal wells in the non-uniform production distribution pattern.Computer program is used to depict the shape of water crest raising,the rationality of model is demonstrated by 3Dvisualized.