水驱油田含水率预测方法研究及拓展

Research on and development of prediction method of water cut in water flooding oilfield

在新型油相相对渗透率曲线的基础上,结合物质平衡方程和Welge方程,导出了一种新型含水率预测模型,并在一定条件下可转化得到Logistic模型。新型含水率预测模型中待定系数与开发动态和地质静态参数变化关系明确,使得许多控水措施更具理论支持。同时,针对目前已有油水相渗曲线与Welge方程结合还无法得到Logistic模型、Goempertz模型以及Usher模型的问题,以及新模型推理过程中要保持开井数不变等条件限制,提出了联解法和直接法建立含水率预测模型。通过两种方法拓展,使得含水率预测模型丰富、多样,能够完全满足描述复杂多样的油田含水率与时间变化过程。后经实例应用,效果较好,值得其他油田借鉴。

On the basis of a new oil phase relative permeability curves,combined with the material balance equation and Welge equation,a new model for predicting water cut is derived.Under certain conditions,it can be converted to the Logistic model.In the new model,the relationship between undetermined coefficients,development dynamic and geological static parameters is clear,so many water control measures have become more theoretically supported.Meanwhile,combined with water-oil relative permeability curves and Welge equation,either the Logistic model,the Goempertz model or Usher model cannot be deduced.Furthermore,some limiting conditions remain in our solution,such the new model requires that the number of wells still not be changed.However,coupling and direct methods have been proposed to build prediction model of water cut.By means of expanding the two methods,with rich,diverse prediction models of water cut,it has been fully possible to describe the complex and diverse water content and process of time change.After field applications of the model,positive results are acquired,and thus may be applied to other oil fields.