低渗透油藏注水开发采收率的正交试验分析研究

针对启动压力梯度在低渗透油藏流体渗流中普遍存在的现象,建立了考虑启动压力梯度的水驱油渗流数学模型,给出了数值求解方法,并开发了相应的注水开发数值模拟软件.以反五点注采井网为例,引入正交试验设计方法,针对地层参数及注水开发参数对采收率的影响进行了直观分析,得到了这两项参数对采收率影响的主次关系,对于指导低渗透油藏注水开发方案的优化设计有一定实用意义.该方法可推广应用于油田开发设计中多参数问题的分析和优选.

Analysis on the orthogonal experiments of recovery efficiency of water - injected reservoirs with low permeability

There commonly exist starting pressure gradient during fluid flow in low-permeability reservoirs. The percolation mathematical model of oil displacement by water considering starting pressure gradient was set up and the numerical solution method was given. Then the numerical simulation software for water-injected reservoirs-considering starting pressure gradient was developed. Taking the inverted five spot flood pattern as an example, orthogonal experiment design method was introduced to directly analyze the effect of the formation and water-injection parameters on the recovery efficiency. The primary and secondary relation of the effect of these parameters on the recovery efficiency were gained. The results had some applicative significance in optimization design of water-injection project in the low-permeability reservoirs. And this method can be extended to analyze and optimize the multi-parameter in the reservoir development design.