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In order to solve the problem/address the issue of oil saturation reduction in the near‐wellbore region of low‐temperature fractured reservoir in Fuyu oilfield, it is especially necessary to carry out in‐depth profile control plugging technology research. In this paper, composite system of particle plugging agent and new interpenetrating network gel were optimally designed, and the non‐fractured cores and fractured cores were used for plugging experiment and oil displacement, the in‐depth profile control mechanism of the composite system was obtained. The results show that the gelation time of the new interpenetrating network gel system can reach 6–7 hours under low temperature conditions (30 °C), with strong shear resistance and viscosity retention. The waterflooding efficiency of fractured core is lower than that of non‐fractured core. After injection of different profile control system, improved recovery efficiency of fractured core is larger than that of non‐fractured core, but the ultimate oil recovery of fractured core is still smaller than that of non‐fractured core. The gelation effect and strength of the composite system are better than that of new interpenetrating network gel agent. The addition of the expanded particles in the system greatly enhances the overall strength and anti‐interference ability. This study can provide theoretical guidance for in‐depth profile control of low temperature fractured reservoirs.

In order to explore the development methods suitable for heterogeneous low permeability reservoirs and study the distribution characteristics of residual oil, photoetched glass and artificial core models with three permeability ratios of 1, 6, and 9 were prepared in this research. Three displacement schemes including polymeric surfactant flooding, polymeric surfactant with binary flooding, and binary flooding were designed at the same expenses to obtain the displacement mechanism of various residual oil saturations. The results show that the best displacement efficiency can be achieved by polymeric surfactant flooding, followed by polymeric surfactant with binary flooding, and binary flooding for the models with the same permeability ratio. Binary flooding mainly activates cluster and oil drop residual oils, polymeric surfactant with binary flooding mainly activates cluster, oil film, and column residual oils, whereas polymeric surfactant flooding mainly activates cluster, oil drop, and column residual oils. In addition, with the increase of the model permeability ratio, the recovery ratio of water flooding decreases, whereas the enhanced oil recovery and the variations in residual oil saturation gradually increase after carrying out different displacement measures. The viscoelastic and shearing effects of the polymeric surfactant flooding system can better displace the residual oil, assisting in the further development of heterogeneous low permeability reservoirs.