Infuence of connate water and condensate saturation on inertial effects ingas/condensate reservoirs

In the near-wellbore region of gas/condensate wells, high-pressure gradient s induce both large condensate saturation and high gas velocities which may lead to significant deviations from Darcy's law for gas permeability. At t he present time, no physically relevant model exists which takes into accou nt these non-Darcian two-phase flow phenomena. Using a specific laboratory equipment, a laboratory study has been performed with the aim to estimate t he influence of pore structure and connate water saturation S-wi on the gas inertial coefficient beta (g) and to integrate the effect of the condensat e dropout in the Forchheimer flow equation. Experiments were conducted on s andpacks and sandstone core samples. For dry gas floods, the measured beta (g) values were found in good agreement with previous published data. For g as floods in presence of S-wi, beta (g) was found to increase with S-wi and a new cor relation between beta (g) and a mean-pore radius (r) over bar is proposed. Gas/condensate (C-1-C-3 mixtures) steady-state experiments showe d that beta (g) values increased with the total liquid saturation.