层间非均质油藏提液效果数值模拟

为了描述提液措施的作用机理,基于黑油模型,考虑启动压力的影响,建立了三维三相数学模型,并采用隐压显饱法进行求解.通过建立概念模型,对渗透率级差、提液幅度、提液时机和初始采液速度对提液效果的影响进行了研究.结果表明,随着渗透率级差的增大,提液提高采收率幅度先增加后减小,渗透率级差为3～7时提液效果最佳;在一定提液幅度下,随着渗透率级差的增大,提液效果逐渐变差,随着提液幅度的增加,提液效果逐渐变好;提液时机越早,越有利于发挥低渗透层的生产能力,提液效果越好;初始采液速度大,渗透率级差大的提液效果好.

Numerical simulation of development effect of enhanced liquid production in heterogeneous reservoirs

In order to describe the mechanism and characteristics of enhanced liquid production in heterogeneous reservoirs, and based on the traditional black oil model, a three-dimensional, three-phase mathematical model, which takes threshold pressure gradient into account, is put forward. And, a corresponding numerical simulator is developed, in which the Implicit Pressure Explicit Saturation Method is used. Through establishing the conceptual models, the influences of permeability ratio (the ratio of highest permeability to lowest permeability), the amplitude and time of enhanced liquid production, and the initial liquid production rate are studied. The results show that: under certain amplitude of enhanced liquid production, the development effect of enhanced liquid production becomes worse with the increase of permeability ratio. The development effect of enhanced liquid production gets better while the amplitude of enhanced liquid production increases. The earlier of enhanced liquid production, the better development effect is. When the initial liquid production rate is larger, the development effect of enhanced liquid production for the model with larger permeability ratio is better.