储层相对渗透率评价方法

Evaluating method of relative permeabilities of a reservoir

确定相对渗透率的方法有实验法(稳态法和非稳态法)、毛管压力法和矿场资料计算法等。对储层渗透率的处理,先由实验得到各块岩心的相对渗透率曲线,然后对曲线归一化再应用于油藏开发设计,归一化的曲线可更准确地反映特定储层的流体渗流特征。相渗曲线大致可以分为5类:水相上凹型(标准型)、水相直线型(直线型)、水相下凹型(弓型)、水相上凸型(驼峰型)、水相靠椅型(直线型和弓型的过渡型),每种曲线对应储集层储集渗流特性不同。相对渗透率曲线是油藏开发中重要资料之一,充分认识油水相对渗透率的确定方法、曲线形态分类、形态变化的影响因素以及相对渗透率曲线的实际应用,对油藏更合理开发具有重要指导意义。

The methods to measure relative permeability contain the following： experiment method （steady-state and unsteady-state methods）, capillary pressure method and calculating method with the help of field data, etc. For the determination of relative permeability, first the permeability of each core must be gotten by experiments and then the above curves must be normalized, finally used in development design of the oil reservoirs, thus ＇the normalized curves can more accurate response the flow characteristics of specified reservoir liquids. Relative permeability curve can generally be classified the following five kinds： upward concave type to water phase （standard type）, straight line type to water phase （ straight line type）, downward concave type to water phase （ bow type）, upward convex type to water phase （ camel peak type） and chair-shaped type to water phase （ the translation type from straight line type to bow one） . Each kind of curve is accordant to different flow characteristics of reservoir liquids. Relative permeability curve is one of important data for oil reservoir development. Both the sufficient understandings of the determining methods, the classification of curve forms, the influencing factors of form changes for oil-and-water relative permeabilities and the actual practice of these relative permeability curves possess significant meaning for the reasonable development of an oil reservoir.