The article presents a geometric method for comparative assessment of formation coverage in steady-state and cyclic waterflooding and an analytical algorithm to divide into groups the injection wells for cyclic waterflooding, taking into account the method of filtration flow redirection. The amount of injection well grouping options for cyclic waterflooding is large enough to calculate each at simulation model. An analytical algorithm has been developed to find the best option for grouping injection wells for cyclic waterflooding, taking into account the method of filtration flow redirection. The area of oil-saturated reservoir zones, additionally involved in production, and their corresponding mobile oil in place are used as the optimization criterion. The main directions of filtration flows are formed in a steady waterflooding and areas of the reservoir that are poorly covered by waterflooding appear. In the first half-cycle of the waterflooding, new directions of filtration flows are formed when some of the injection wells are shut down. Similarly, in the second half-cycle of waterflooding. By obtaining the resulting area of coverage of the oil in place by active production zones after two half-cycles and using the map of current mobile oil in place, we can determine the reserves involved in active production for this grouping of injection wells. The analysis showed that there is a sufficient correlation between the value of additionally covered current mobile oil in place as a result of filtration flow redirection, obtained by analytical evaluation, and technological efficiency, obtained by the results of calculations at simulation model. The results of the analytical evaluation significantly reduce the total time of calculations at simulation model, which allows in a short time to make a decision on the choice of the optimal case of cyclic waterflooding for implementation in the oilfield.
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