A method for quantitative description of the dominant channel with high speed Non-Darcy flow

Author of the article:CHEN Cunliang, WANG Yu, YUE Baolin, YANG Ming, MA Dong

Author's Workplace：CNOOC (China) Tianjin Branch, Tianjin, 300459, China

Key Words：Non-Darcy flow; High water-cut; Dominant channel; Quantitative; Interwell connectivity

Abstract：The development of the dominant channel seriously affects the water-flooding effect of the oil field, and leads to the deterioration of recovery rate. How to effectively describe the dominant channel is an urgent issue to further improve the recovery rate of water-flooding in high water cut oil field. Therefore, the quantitative calculation of the dominant channel’s parameters is carried out using the seepage theory and the mathematical means. The reservoir that develops the dominant channel is regarded as the parallel of the normal reservoir and the dominant channel. The ineffective water injection is calculated from the ineffective circulating water model. According to the principle of equivalence, the ineffective water production of the oil well and the water production of the normal reservoir are calculated. Then the dominant channel volume and the seepage velocity of the fluid in the channel are quantitatively described by the volume analogy formula and non-Darcy flow. The interwell connectivity model is used to calculate the parameters of the dominant channel in the well group and is applied to an offshore oil field X. The results are in good agreement with the dynamic analysis, which verifies the reliability of the method. It is suggested that the reagents with larger particle size should be selected to carry out the profile control, after which the daily oil increase in the block is nearly 60 m3 /d, and the water content rate is reduced by 10%. The results of the study provide a technical reference for the identification and management of dominant channels in oil fields at high water-cut period.