水驱油藏中微观注水倍数计算方法

常规岩心驱替实验中的注水倍数与整个油藏中注水倍数不一致,导致岩心驱替实验成果难以较好的应用到油藏开发计算中,因此需要知道地层中的微观注水倍数(也有的称为过水倍数)的分布,该微观注水倍数要求与岩心驱替实验中的注水倍数相一致。以五点法井网为例,确定了地层中的流线分布。流体是沿流线做一维流动,将每一条流线可看作是由若干个岩心连接而成,这样通过一维水驱油理论,可计算得到流线上的饱和度分布以及每个岩心的注水倍数,从而确定地层中的微观注水倍数分布。可以将岩心驱替实验的注水倍数与地层中的微观注水倍数相匹配。对于如何将岩心驱替实验结果应用到油藏开发指标计算中提出了合理的解决办法,具有重要的理论和实际意义。

The Calculation Method of Micro Water Injection Multiple in Water Drive Reservoirs

In order to know the distribution of micro water injection pore volume multiple in the formation which is consistent with that in the core displacement experiment, the streamline distribution calculation model was proposed. The case of the Five-spot Well Pattern was studied in order to determine the streamline distribution in the formation. Fluids flow one-dimensionally along the streamline and each streamline can be seen as the connection of a number of cores. The flowing resistance on each streamline was measured to determine the water injection rate of each streamline. According to the theory of one-dimensional oil-water two phase flow, the water injection pore volume multiple of each core in the streamline could be calculated in order to obtain the distribution of the water injection pore volume multiple in the formation. Thus, the consistence would be achieved between the multiple of water injection in core displacement experiment and that in the formation. The research results was of high theoretical and practical significance to the application of the results of core displacement experiment to the research of reservoir development.