The traditional waterflood management practice during the oil field development is to divide the production targets into blocks / elements / patterns. This allows us to estimate reservoir and production parameters, to identify problem blocks and plan for well activities, improving the reservoir development efficiency.
The input data for calculating key indicators of block energy state and waterflood performance are related to production and injection per blocks. Therefore, the cornerstone is the production / injection allocation for the wells located on boundaries of several blocks.
Generally, production / injection is allocated using the geometrical technique, where the contribution of a boundary wells into each block (described by an allocation factor) is proportional to the angle, open to flow in this well into the block. Furthermore, this proportion is retained during the entire field life. However, the development practice shows that actual allocation factors may differ significantly from the numbers, predicted by the geometrical approach. Moreover, these factors dynamically change over time with changes in performance of the wells, located inside the block.
In this paper, we describe the results of a comparative analysis on various static and dynamic techniques for calculating well allocation factors. We determined the limitations of various methods and estimated the performance factor accuracy for different waterflooding patterns.