The effect of a microscale fracture on dynamic capillary pressure of two-phase flow in porous media Academic Article uri icon

abstract

  • 2018 Elsevier Ltd Dynamic capillary pressure (DCP) effects, which is vital for predicting multiphase flow behavior in porous media, refers to the injection rate dependence capillary pressure observed during non-equilibrium displacement experiments. However, a clear picture of the effects of microscale fractures on DCP remains elusive. This study quantified the effects of microscale fractures on DCP and simulated pore-scale force and saturation change in fractured porous media using the multiphase lattice Boltzmann method (LBM). Eighteen simulation cases were carried out to calculate DCP as a function of wetting phase saturation. The effects of viscosity ratio and fracture orientation, aperture and length on DCP and DCP coefficient were investigated, where refers to the ratio of the difference of DCP and static capillary pressure (SCP) over the rate of wetting-phase saturation change versus time. Significant differences in values were observed between unfractured and fractured porous media. The values of fractured porous media were 1.1 104 Pa ms to 5.68 105 Pa ms, which were one or two orders of magnitude lower than those of unfractured porous media with a value of 4 106 Pa. ms. A horizontal fracture had greater effects on DCP and than a vertical fracture, given the same fracture aperture and length. This study suggested that a microscale fracture might result in large magnitude changes in DCP for two-phase flow.

published proceedings

  • ADVANCES IN WATER RESOURCES

author list (cited authors)

  • Tang, M., Lu, S., Zhan, H., Guo, W., & Ma, H.

citation count

  • 27

complete list of authors

  • Tang, Mingming||Lu, Shuangfang||Zhan, Hongbin||Guo, Wenqjie||Ma, Huifang

publication date

  • January 2018