The Detectable Radius of an Oil Well Considering Pressure Gauge Resolution Ratio

Abstract:

For a case of constant-rate liquid production from a single well centered in a horizontal, homogeneous-acting, isopachous, and infinite reservoir, based on fundamentals of fluid flow in porous media the bottom hole flowing pressure never stabilize. In the process of field well testing, however, pressure values measured by the pressure gauge which has a definite resolution value will not change after a period, so the bottom hole flowing pressure can be considered to be stabilized. According to this situation, through theoretical derivation, a stabilized time formula is firstly proposed, by which the time after which the bottom hole flowing pressure measured with a pressure gauge will be stabilized can be calculated, and the stabilized time for a given pressure gauge is in direct proportion to the liquid producing rate, but in inverse proportion to the resolution ratio of the pressure gauge. Applied the stabilized time formula, a new formula of detectable radius can be derived, by which the effect of resolution of the pressure gauge can be considered. Secondly, the time after which the value of the pressure gauge measured in the bottom hole of the observation well starts to change during interference testing is obtained, and the time is related to the fluid flow rate and the distance between the producing well and the observation well. The conclusion can be applied as a reference in the design process of working system during well testing.

• Periodical: Advanced Materials Research (Volumes 560-561)
• Pages: 1188-1194
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.560-561.1188
• Online since: August 2012
• Authors: Jun Tai Shi, Xiang Fang Li, Lei Zhang, Wei Na Ren, Le Zhong Li, Hui Du
• Keywords: Detectable Radius, Interference Testing, Pressure Gauge, Resolution Ratio, Well Testing

References

[1] W. J. Lee, Well Testing, Texas: Textbook Series, SPE, Richardson, 1977.

[2] J. Lee, R.A. Wattenbarger, Gas Reservoir Engineering, Texas: Textbook Series, SPE, Richardson, 1996.

[3] R. C., Earlougher. Advances in Well Test Analysis, Texas: Monograph Series, SPE, Richardson, 5.

[4] J. Zhang, G. Lei, Y. Zhang, Fluids flow in porous media, Dongying: China Petroleum University Press, 2006.

[5] Z. Lang, Oil and gas fluids flow in porous media underground, Dongying: China Petroleum University Press, 2001.

[6] X. Wang, S. Ma, A simple method for determination of radius of investigation for non-newtonian fluids and other non-ideal systems, Paper SPE 37410 presented at the Production Operations Symposium, Oklahoma City, Oklahoma, 9-11 March 1997, SPE 37410-MS.

DOI: 10.2118/37410-ms

[7] X. Wang, T. Lei, J. Yang, S. Lei, The Relationship between Investigation Radius and Formation Damage, Well testing, 2002, 11(3): 1-2.

[8] W. Mao, New computing method for radius of investigation based on flow rate, PGRE. 2006, 13(1): 77-78.

[9] C. Li, Deliberation on the paper "New computing method for radius of investigation based on flow rate, PGRE. 2007, 14(3): 77-79.

[10] L. Qi, X. Wang, Study on determination of radius of investigation, Well testing. 2007, 16(2): 1-3.

[11] Z. Wang, X. Wang, The radius of investigation in pressure sensitive reservoir, Journal of Oil and Gas Technology. 2005, 27(4): 440-441.