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Nodal Analysis Estimates of Fluid Flow from the BP Macondo MC252 Well



George Guthrie, Rajesh Pawar, Curt Oldenburg, Todd Weisgraber, Grant Bromhal, Phil Gauglitz, John Bernardin, David Dixon, Rick Kapernick, Bruce Letellier, Brett Okhuysen, Robert Reid, Barry M. Freifeld, Karsten Pruess, Lehua Pan, Stefan Finsterle, George J. Moridis, Matthew T. Reagan, Thomas A. Buscheck, Christopher M. Spadaccini, Roger D. Aines, Brian Anderson, Robert Enick, Roy Long, Shahab Mohaghegh, Bryan Morreale, Neal Sams, Doug Wyatt, L A. Mahoney, J A. Bamberger, J Blanchard, J Bontha, C W. Enderlin, J A. Fort, P A. Meyer, Y Onishi, D M. Pfund, D R. Rector, M L. Stewart, B E. Wells, S T. Yokuda, Antonio Possolo, William F. Guthrie, Pedro I. Espina


The Nodal-Analysis Team within the Flow Rate Technical Group predicted the flow-related pressure drops from the reservoir to release points to estimate flow rates for various time periods for the Macondo well. These estimates were based on predictions from teams at five different DOE national labs, each using different approaches. The data used in the effort were restricted to publically available information and a limited amount of proprietary information provided as part of the regulatory process. Nevertheless, the nodal analysis provided bounds for the flow rates that were consistent across the approaches and were consistent with estimates of flow developed by other techniques (including direct measurement of pressure drops across the blow-out preventer). In addition, the Nodal Analysis Team explored the uncertainty in the estimates associated with incompletely known and variable parameters (such as reservoir permeability, as reflected in variations in bottom hole pressures) and associated with unknown parameters (such as flow path within the wellbore). This uncertainty analysis showed that flow scenario in the wellbore was the single biggest factor in estimating flow rate, resulting in two possible distributions of rate (based on the uncertainties in the other factors). Other factors that were found to be important in determining flow rate included bottom-hole pressure, resistance in the blowout preventer, casing roughness, gas-oil ratio, and resistance associated with closure or reduced flow in the drill pipe.
Assessment of Flow Rate Estimates for the Deepwater Horizon / Macondo Well Oil Spill
Publisher Info
U.S. Department of the Interior, Washington, DC


nodal analysis of fluid flow, BP Macondo MC252 well, uncertainty assessment, Flow Rate Technical Group.


Guthrie, G. , Pawar, R. , Oldenburg, C. , Weisgraber, T. , Bromhal, G. , Gauglitz, P. , Bernardin, J. , Dixon, D. , Kapernick, R. , Letellier, B. , Okhuysen, B. , Reid, R. , Freifeld, B. , Pruess, K. , Pan, L. , Finsterle, S. , Moridis, G. , Reagan, M. , Buscheck, T. , Spadaccini, C. , Aines, R. , Anderson, B. , Enick, R. , Long, R. , Mohaghegh, S. , Morreale, B. , Sams, N. , Wyatt, D. , Mahoney, L. , Bamberger, J. , Blanchard, J. , Bontha, J. , Enderlin, C. , Fort, J. , Meyer, P. , Onishi, Y. , Pfund, D. , Rector, D. , Stewart, M. , Wells, B. , Yokuda, S. , Possolo, A. , Guthrie, W. and Espina, P. (2011), Nodal Analysis Estimates of Fluid Flow from the BP Macondo MC252 Well, Assessment of Flow Rate Estimates for the Deepwater Horizon / Macondo Well Oil Spill, U.S. Department of the Interior, Washington, DC (Accessed April 18, 2024)
Created March 9, 2011, Updated October 12, 2021