Gas-Condensate Flow in Perforated Regions
- Mahmoud Jamiolahmady (Heriot-Watt University) | Ali Danesh (Heriot-Watt University) | Mehran Sohrabi (Heriot-Watt University) | Rahim Ataei (Heriot-Watt University)
- Document ID
- Society of Petroleum Engineers
- SPE Journal
- Publication Date
- March 2007
- Document Type
- Journal Paper
- 89 - 99
- 2007. Society of Petroleum Engineers
- 5.2.2 Fluid Modeling, Equations of State, 5.4 Enhanced Recovery, 5.4.2 Gas Injection Methods, 5.1 Reservoir Characterisation, 3.2.3 Hydraulic Fracturing Design, Implementation and Optimisation, 5.3.1 Flow in Porous Media, 5.2 Reservoir Fluid Dynamics, 4.6 Natural Gas, 5.6.4 Drillstem/Well Testing, 4.1.2 Separation and Treating, 4.3.4 Scale, 1.6.9 Coring, Fishing, 5.3.2 Multiphase Flow, 2.2.2 Perforating, 1.2.3 Rock properties, 5.2.1 Phase Behavior and PVT Measurements
- 8 in the last 30 days
- 883 since 2007
- Show more detail
- View rights & permissions
|SPE Member Price:||USD 10.00|
|SPE Non-Member Price:||USD 30.00|
The most crucial region with regard to affecting well productivity is the perforated region. Considerable effort has been directed to study this subject mathematically by many investigators, but they have been mainly focused on single-phase flow, while two-phase flow has received less attention.
It has been demonstrated, first by Danesh et al. (1994) and subsequently by other researchers (Henderson et al. 1995; Blom et al. 1997; Ali et al. 1997), that the gas and condensate relative permeability (kr ) can increase significantly by increasing the flow rate, contrary to the common understanding. This effect, known as positive coupling, complicates the flow of gas and condensate near the wellbore even further when it competes with the inertial forces at higher velocities typical of those around perforation tips.
The flow of gas and condensate in the perforated region was studied in this work using a finite-element modeling approach. The model allows for changes in fluid properties and accounts for the positive coupling and negative inertial effects using a fractional-flow-based relative-permeability correlation. A sensitivity analysis on the impact of perforation characteristics such as density, phasing, length, and radius as well as that of fluid properties, rock characteristics, wellbore radius, fractional flow, and rate on well productivity was conducted, resulting in some valuable practical guidelines for optimum perforation design.
The effect of perforation characteristics on the well flow efficiency has been studied by many investigators. Muskat presented the first analytical treatment of the problem (1943). In his analysis, perforations were represented by mathematical sinks distributed spirally around the wellbore but did not extend into the formation. Other early investigators used the finite-difference modeling technique to examine the productivity aspects of perforated completions (Harris 1966; Hong 1975). However, because of the limitations of the finite-difference method, these studies considered mostly unrealistic perforation geometries to avoid mathematical complexities. Later investigators applied the finite-element method, which models the geometry of the perforation with greater precision (Locke 1981; Tariq 1987).
Tariq (1987) presented results of finite-element modeling of single-phase steady-state flow in perforated completions with and without the non-Darcy (inertial) effect for a linear core and a full 3D system. Although his results for single-phase flow are widely used, there are reports on lack of required accuracy at large perforation lengths and in the non-Darcy cases (Behie and Settari 1993; Jamiolahmady et al. 2006a).
|File Size||1 MB||Number of Pages||11|
Ali, J.K., McGauley, P.J., and Wilson, C.J. 1997. The Effects of High-Velocity Flow andPVT Changes Near the Wellbore on Condensate Well Performance. Paper SPE38923 presented at the SPE Annual Technical Conference and Exhibition, SanAntonio, Texas, 5-8 October. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=38923-MS.
Behie, G.A. and Settari, A. 1993. Perforation Design Models forHeterogeneous, Multiphase Flow. Paper SPE 25901 presented at the SPE LowPermeability Reservoirs Symposium, Denver, 26-28 April. DOI: http://www.spe.org/elibrary/servlet/spepreview?id=25901-MS.
Blom, S.M.P., Hagoort, J., and Soetekouw, D.P.N. 1997. Relative Permeability atNear-Critical Conditions. Paper SPE 38935 presented at the SPE AnnualTechnical Conference and Exhibition, San Antonio, Texas, 5-8 October. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=38935-MS.
COMSOL (Femlab) Multiphysics Reference Manuals. 2002. Version 220.127.116.11.COMSOL Inc.
Danesh, A., Khazam, M., Henderson, G.M., Tehrani, D.H., and Peden, J.M.1994. Gas Condensate Recovery Studies. Paper presented at the DTI Improved OilRecovery and Research Dissemination Seminar, London, June.
ECLIPSE Reference Manuals. 2002. Version 2002A. Schlumberger.
Forchheimer, P. 1914. Hydraulik. Ch. 15. Berlin. 116-118.
Harris, M.H. 1966. The Effect ofPerforating on Well Productivity. JPT 18 (6): 518-528;Trans., AIME, 237. SPE-1236-PA. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=1236-PA.
Henderson, G.D., Danesh, A., Tehrani, D.H., and Peden, J.M. 1995. The Effectof Velocity and Interfacial Tension on the Relative Permeability of GasCondensate Fluids in the Wellbore Region. Paper presented at the EuropeanSymposium on Improved Oil Recovery, Austria.
Henderson, G.D., Danesh, A., and Tehrani, D.H. 2001. Effect of Positive RateSensitivity and Inertia on Gas Condensate Relative Permeability at HighVelocity. Petrol. Geosci. 7: 45-50.
Hong, K.C. 1975. Productivity ofPerforated Completions in Formations With or Without Damage. JPT27 (2): 1027-1038; Trans., AIME, 259. SPE-4653-PA. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=4653-PA.
Jamiolahmady, M. and Danesh, A. 2005. Flow in Perforated Region IncludingNonlinear Effects. Paper presented at the EAGE Conference and Exhibition,Spain, June.
Jamiolahmady, M., Danesh, A., Tehrani, D.H., and Duncan, D.B. 2001. A Mechanistic Model ofGas-Condensate Flow in Pores. Transport in Porous Media41(1): 17-46. DOI: http://dx.doi.org/10.1023/A:1006645515791.
Jamiolahmady, M., Danesh, A., Tehrani, D.H., and Duncan, D.B. 2003. PositiveEffect of Flow Velocity on Gas-Condensate Relative Permeability: NetworkModelling and Comparison with Experimental Results. Transport in PorousMedia 52 (2): 159-183. DOI:http://dx.doi.org/10.1023/A:1023529300395.
Jamiolahmady, M., Danesh, A., and Duncan, D.B. 2005. An improvedunderstanding of positive velocity dependency of gas-condensate relativepermeability: a mechanistic approach. Paper presented at the World Congress ofChemical Engineering, Glasgow, July.
Jamiolahmady, M., Danesh, A., and Sohrabi, M. 2006a. Flow around a rockperforation surrounded by damaged zone: Experiments vs. Theory. J. Petrol.Sci. Engng. 50: 102-114.
Jamiolahmady, M., Danesh, A., and Duncan, D.B. 2006b. Measurement andModelling of Gas Condensate Flow Around a Rock Perforation. Transport inPorous Media 63 (2): 323-347.
Jamiolahmady, M., Danesh, A., Tehrani, D.H., and Sohrabi, M. 2006c. Variations of Gas/Condensate RelativePermeability With Production Rate at Near-Wellbore Conditions: A GeneralCorrelation. SPEREE 9 (6): 688-697. SPE-83960-PA. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=83960-PA.
Locke, S. 1981. An AdvancedMethod for Predicting the Productivity Ratio of a Perforated Well.JPT 33 (2): 2481-2488. SPE-8804-PA. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=8804-PA.
Matlab Reference Manuals. 2003. Version 6.5. MathWorks Inc.
Muskat, M. 1943. Effect of Casing Perforations on Well Productivity.Trans., AIME, 151. 175-187.
Sage, B.H., Hicks, B.L., and Lacey, W.N. 1940. Phase equilibria inhydrocarbon systems: The Methane-n-Butane systems in the two-phase region.Industrial and Engineering Chemistry 32: 1058-1092.
SUPERTRAPP (NIST Thermophysical Properties of Hydrocarbon Mixture Database)User's Guide by National Institute of Standards and Technology (NIST). 1992.Version 1.0. NIST Standard Reference Database 4.
Tariq, S.M. 1987. Evaluation ofFlow Characteristics of Perforations Including Nonlinear Effects With theFinite-Element Method. SPEPE 2 (2): 104-112; Trans.,AIME, 283. SPE-12781-PA. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=12781-PA.
Weinaug, C.F. and Katz, D.L. 1943. Surface Tension of Methane-PropaneMixtures. Industrial and Engineering Chemistry 35 (2):239-246.