Petroleum Reservoir Evaluation and Development ›› 2023, Vol. 13 ›› Issue (5): 686-694.doi: 10.13809/j.cnki.cn32-1825/te.2023.05.016

• Comprehensive Research • Previous Articles     Next Articles

Analysis of pressures in water injection wells considering fracture influence induced by pressure-drive water injection

CUI Chuanzhi1(),LI Huailiang1,WU Zhongwei1,ZHANG Chuanbao2,LI Hongbo2,ZHANG Yinghua2,ZHENG Wenkuan2   

  1. 1. College of Petroleum Engineering, China University of Petroleum(East China), Qingdao, Shandong 266580, China
    2. Research Institute of Exploration and Development, Sinopec Shengli Oilfield, Dongying, Shandong 257015, China
  • Received:2022-09-19 Online:2023-11-01 Published:2023-10-26

Abstract:

The analysis of the well bottom pressure of the pressure-drive injection wells is of great significance for the evaluation of the pressure-drive effect and the inversion of reservoir parameters. In order to obtain the bottom hole pressure response of pressure-drive injection wells and the dynamic fracture parameters generated by pressure drive water injection, and from an fracture propagation perspective, the seepage mechanics theory and numerical simulation method are used to form a pressure analysis model of water injection wells considering the effects of fracture propagation, fracture morphology, filtration of injected fluid and other factors, and obtain the bottom hole pressure response of pressure drive water injection wells. The effects of injection flow, liquid production, formation permeability and well spacing on pressure are analyzed respectively, and applied to actual pressure drive wells to verify the accuracy of the model. It is found that the fluid flow in pressure-drive injection wells can be divided into five flow stages, namely, initial fracturing stage, fracture expansion stage, linear flow stage, transitional flow stage and boundary controlled flow stage. With the increase of injection flow rate, the fracture expansion stage is more obvious, the liquid production is greater, and the upwarping amplitude of the double logarithmic pressure analysis curve gets smaller in the late stage of pressure drive water injection. This study is of great significance to the study and understanding of the mechanism of unstable seepage flow in low permeability reservoirs developed by pressure drive water injection, and to the influence of dynamic fractures in water injection wells on bottom hole pressure.

Key words: pressure-drive, water injection well, pressure analysis, dynamic fractures propagation, fracturing fluid leak-off

CLC Number: 

  • TE357