Volume 52

A Physics-based Data-driven Simulation Method Coupling the Time-varying Properties and High-speed non-Darcy Flow under Waterflooding Boying Li, Xinwei Liao, Lingfeng Zhang, Dongzhi Yan, Zhonghao Li

Abstract

For long-term waterflooding reservoirs with strong heterogeneousness, the high-intensity water flooding has caused significant time-variation in reservoir properties; Meanwhile, there are varying degrees of high-speed non-Darcy flow features in the thief zone. In this paper, a new physical-based dimensionality reduction numerical simulation method is proposed, which takes the one-dimensional connection flow units as the research object, with the dynamic transmissibility and pore volume as the characteristic parameters. By coupling the time-varying properties and high-speed non-Darcy flow, a fine simulation of strongly heterogeneous reservoirs considering the thief zone in long-term waterflooding has been realized. We analyze the effects of time-varying physical properties and high-speed non-Darcy flow on the dynamics of long-term waterflooding taking the channelized Egg model as an example. The results show that by the high-intensity water flooding, the physical properties and conductivity of the thief zone become better, which accelerates the waterflood front broken, the water cut rises, and the residual oil between the wells is enriched; On the opposite side of the small pore throat. Influenced by the non-Darcy flow in the thief zone, the conductivity and fluid seepage capacity in the thief zone decreases, and the inhibition of the water is more significant, and more water flows to the small pore throat, which enlarges the swept volume, and facilitates the recovery. Based on the method proposed in this article, a more precise and efficient simulation of heterogeneous waterflooding reservoirs has been achieved.

Keywords dimensionality reduction simulation, long-term waterflooding, high-speed non-Darcy flow, physical properties time variation, inter-well connectivity