Simulation of the Static Sealing Performance of Rubber Packer Cylinders in a Supercritical–CO₂ Environment

Abstract

The aim of this study was to solve the problems associated with the sealing and tearing failure of rubber packer cylinders during CO2 downhole injection. Using Comsol Multiphysics 6.0 software, a rubber cylinder model in a supercritical CO2 (SC–CO2) environment was established. The thermal analogy method was used to simulate the CO2 diffusion and rubber cylinder swelling process. We analyzed the deformation and stress of the rubber cylinder that was caused by temperature and pressure, with CO2 as the swelling agent. The results show that in the SC–CO2 environment, under the influence of CO2 diffusion and the consequent swelling, the rubber cylinder body is prone to large deformations, and the maximum shear stress is significantly increased, leading to the shear failure of the rubber cylinder. Reducing the initial seating pressure can alleviate the impact of deformation, whereas reducing the maximum contact pressure can cause the rubber cylinder to lose its seal. We also analyzed the influence of various factors on the maximum contact stress of the rubber cylinder, providing a theoretical basis and technical support for improving the sealing performance of rubber packer cylinders in an SC–CO2 environment.

Keywords

• supercritical–CO₂
• rubber packer cylinder
• sealing performance
• swelling