Numerical and experimental investigation of a novel perforation technique in petroleum wells - Perforation by drilling Conference Paper uri icon

abstract

  • The objective of perforating is to maximize well productivity by establishing good connectivity between the wellbore and formation. It is known that conventional method of perforation, using explosive charges, does not achieve expected well productivity due to a region of reduced permeability around the perforation tunnel. The results of an experimental and numerical program developed to investigate the impact of Perforating by Shooting (PS) in cylindrical sand samples with varying amounts of strength and porosity are presented in this paper. A new technique, Perforating by Drilling (PD) is proposed and the performance PD technique is compared with that of the PS technique. Furthermore, in order to gain an appreciation of a "perfect" perforation, results are compared with the Casting technique. Fluid flow rate and differential pressure across the perforated samples were measured for three different types of samples using "Geotechnical Digital System" triaxial testing set-up. Fluid flow rate with changing differential pressure and finally pressure build-up data with time profile indicates the PD technique can achieve maximum wellbore productivity compared to the PS technique. Results indicate that at 100 kPa differential pressure the PS, PD and Casting techniques can achieve 0.20 mL/s, 0.65 mL/s and 1.00 mL/s fluid flow rates respectively across a sample. A 1-D time dependent porous media flow model was implemented to simulate flow across the perforated cylindrical samples created by the PS, PD and Casting techniques. Good consistency is obtained between the experimental and numerical results.

author list (cited authors)

  • Rahman, M. A., Biazar, J., Koksal, M., & Islam, M. R.

publication date

  • December 2005