Abstract:

Relative permeability curves are the main characteristics of two-phase fluid flow in laboratory test. In light of the relative permeability curve and material balance principle, the present paper, based on different relative-permeability curve patterns, deduced the generalized Arps decline model under the voidage balance condition, i.e. exponential, hyperbolic and harmonic decline equations. The paper also analyzed the conditions under which the generalized model was simplified into a conventional one and described the important impact of oil-phase relative permeability characteristics on parameters of production-decline types and models. The application results indicated that the generalized Arps model could effectively describe the production-decline rule of low-permeability reservoirs. The curve patterns of oil-phase relative permeability determined the decline type, the faster the oil-phase relative permeability declined, the greater the output-decline rate was.

Key words: low-permeability reservoir, relative-permeability curve pattern, material-balance principle, production-decline equation, decline type

摘要：

从相对渗透率曲线和物质平衡原理出发，根据不同的相对渗透率形态推导出注采平衡条件下Arps广义递减模型，即指数型、双曲型和调和型产量递减方程，分析了广义模型简化为常规模型的条件，指出油相相对渗透率曲线特性对产量递减类型和递减模型参数的重要影响。实际应用结果表明，Arps广义模型能有效描述低渗透油田的产量递减规律。油相相对渗透率曲线形态决定产量递减类型，油相相对渗透率递减越快，产量递减率越大。

关键词: 低渗透油藏, 相对渗透率曲线形态, 物质平衡原理, 产量递减方程, 递减类型