Mantecon J.C.,SPT Group |
Society of Petroleum Engineers - SPE Asia Pacific Oil and Gas Conference and Exhibition 2012, APOGCE 2012 | Year: 2012
This paper describes the use of multiphase flow numerical transient simulation to assist a petroleum engineer in making proper critical decisions during supervision of well cleanup operations on a rig, and initial well startup operations on a Floating Production Storage and Offloading facility (FPSO). Eni JPDA 06-105 operates the Kitan oil field located in the Joint Petroleum Development Area (JPDA) between East Timor and Australia. The Kitan oil field consists of three subsea intelligent wells, subsea flowlines, risers, and one FPSO. The three wells were completed and cleaned up using the rig before the FPSO arrived on location. The intelligent completions were modeled in detail using commercial dynamic simulation software to establish a sound and safe operating procedure for the well cleanup and well test. The simulation results provided the petroleum engineer on the rig with key operational information, such as the time for the oil to arrive at surface, expected pressure at the down-hole gauges (DHGs) and upstream of the choke manifold, etc. This enhanced the ability of rig site supervisors to anticipate well behavior, enabling a significant risk reduction. The well models were successfully validated with the data obtained after the well cleanup and well testing campaign was finished. The validated well models were integrated with flowline and riser models to investigate the optimum field startup operations and to overcome constraints in the production system which emerged late in the project. Different topside choke and multi-stage hydraulic down-hole flow control valves (FCVs) opening schedules were tested to predict pressure and temperature at the DHGs, the subsea tree (SST) and the FPSO, as well as the flow rates and oil arrival time at the FPSO. The dynamic simulation results played an important role in defining a sound and safe operating procedure for the well cleanup and well test, and initial field startup, providing the offshore petroleum engineer with reliable operating guidelines. Copyright 2012, Society of Petroleum Engineers.
Zubarev D.I.,SPT Group
JPT, Journal of Petroleum Technology | Year: 2010
A comparative study was made of proxy-modeling methods (also known as surrogate modeling or metamodeling) as a computationally inexpensive alternative to full numerical simulation in assisted history matching, production optimization, and forecasting. The study demonstrated the solutionspace complexity for different simulation models and the applicability of the proxy models to mimic it. Focus was given to practical aspects of model construction and to limitations of which engineers should be aware.
Kumar L.,Norwegian University of Science and Technology |
Lawrence C.,Institute for Energy Technology of Norway |
Lawrence C.,SPT Group |
Sjoblom J.,Norwegian University of Science and Technology
RSC Advances | Year: 2014
Pressure propagation in the soft gels is commonly considered either in terms of acoustic waves or gel degradation. However, in a complete description, acoustic, viscous and gel degradation effects should all be considered simultaneously. Here a creep model is discussed with a suitable time scale. The model predicts a specific mechanism of pressure propagation, indicating that gel behaves like a creeping fluid rather than a fluid shearing only above a critical yield stress. The characteristics of pressure propagation can be used to distinguish between creeping and yield stress fluid. The presented results provide a new physical interpretation of recent experimental data. It is also shown that heterogeneity in the gel can cause center-core cohesive failure, as opposed to the near-wall failure which occurs in homogeneous gels. © 2014 the Partner Organisations.
Hissong D.W.,ExxonMobil |
Pomeroy J.,ExxonMobil |
Norris H.L.,SPT Group
Journal of Loss Prevention in the Process Industries | Year: 2014
For releases of hydrocarbons from a subsea pipeline, riser, or production facility, the shape of the plume rising through the water must be predicted prior to any assessment of gas dispersion, liquid pools, or fire above the water surface. The location and size of the plume at the water surface are key parameters for subsequent consequence modeling. A mechanistic model has been developed to predict the plume trajectory and size, based on mass and momentum balances and an empirical water entrainment ratio from the literature. With suitable physical property values available, the model is applicable to releases of gas and/or liquid hydrocarbons, predicting the vaporization and vapor expansion due to decreasing hydrostatic pressure as the plume rises through the water. Some validation of the model was obtained with 16 tests in a small-scale transparent tank. The data cover a wide range of flow rates, including both choked and unchoked flow. The predicted and measured trajectories (centerline displacement) agreed reasonably well. Predictions of the model are presented for three fluids. The model is valuable for assessing the consequences of underwater hydrocarbon releases, providing input for subsequent modeling of gas dispersion or liquid pools and pool fires. © 2013 Elsevier Ltd.
Shi H.,British Petroleum |
Norris L.,SPT Group
Proceedings - SPE Annual Technical Conference and Exhibition | Year: 2011
A subsea single line tie back in the deepwater of the Gulf of Mexico was recently started up. In order to validate the three-phase transient models used in the studies of the field operations, simulations of the activities actually performed in the initial startup were conducted. Comparisons between simulated and actual start-up operations also serve to improve multiphase flow modeling capabilities for future field design and operations. Formation drawdown, Production Index (PI), arrival pressure, and dead oil circulation rate were all constrained to track actual values during the initial startup. The impact of using different fluid properties was also investigated. In addition, dead oil circulation was simulated by several options to determine which method best matches the field data. The simulated values of liquid flow rates, pressures and temperatures were found to be in reasonable agreement with the data. The slugging event experienced by the field was also captured by the simulation. Comparisons between the simulations and field data served to identify both the strengths and weaknesses of the simulator applied to field operations. Copyright 2011, Society of Petroleum Engineers.