A Method for Determining Well Locations in High Water-cut Oilfields Based on Evolutionary Algorithm

Abstract

The invention provides a method for determining a well location in a high water-cut oil field based on an evolutionary algorithm, comprising the steps of: establishing a reservoir model of a predetermined oil area, dividing the reservoir model into grids; Combined to obtain the remaining oil potential enrichment area; calculate the remaining oil potential enrichment area in the remaining oil potential enrichment area, which represents the distribution of remaining oil and the well location constraint value of the injected water sweep volume, and obtain the well location advantage area; use the evolutionary algorithm to iterate the oil wells in the advantage area Calculate the fitness function, use the kriging algorithm to evaluate the fitness function, the evolutionary algorithm is adjusted according to the fitness function, the kriging algorithm considers multi-dimensional space, nugget effect and local weight; iteratively calculates according to the evolutionary algorithm, and obtains the maximum fitness degree function value to determine the well location. The invention uses the improved evolutionary algorithm and Kriging algorithm as optimization tools, constructs a dynamic potential index to narrow the search space of the evolutionary algorithm, and greatly increases the convergence accuracy and speed of optimization calculation.

Description

technical field [0001] The invention belongs to the technical field of adjusting well positions for development of high water-cut oilfields, and in particular relates to a method for determining well positions in high-water-cut oilfields based on an evolutionary algorithm. Background technique [0002] For the oil reservoirs developed by water flooding in my country, most of them are old oilfields with high water content that have been developed by water flooding for decades. The heterogeneity of underground reservoirs and the complexity of oil-water relationship lead to the distribution of remaining oil being "scattered overall and concentrated locally". "The complex characteristics of the oil field caused great difficulties to the late adjustment of the oil field, and directly affected the water flooding development effect and economic benefits. Determining a reasonable adjustment of the well location is an important main technology for the adjustment of high water-cut matu...

AI Technical Summary

Problems solved by technology

Although the current quality map method considers some static and dynamic attributes of the reservoir, it does not consider the influence of the reservoir driving mechanism, the drainage of the existing well pattern, and the swept volume of injected water on the adjusted well location, which has caused a great impact on the optimized well location. certain error

Images