Inflow Performance and Pressure Interference in Dual-Completed Wells With Water Coning Control

2002 ◽  
Vol 124 (4) ◽  
pp. 253-261 ◽  
Author(s):  
Andrew K. Wojtanowicz ◽  
Ephim I. Shirman
Keyword(s):  
Three Dimensional ◽  
Maximum Pressure ◽  
Water Drainage ◽  
Two Phase ◽  
Drainage Rate ◽  
Water Coning ◽  
Water Cut ◽  
Downhole Water Sink ◽  
Inflow Performance ◽  
Well Completions

Dual-completed wells with Downhole Water Sink (DWS) are used for water coning control in oil reservoirs with bottom water drive. In DWS wells, the second (bottom) completion—placed in the water column—is used for draining water. This prevents the water cone invasion and allows free oil inflow in the top completion. The decision on using DWS or a conventional (single-completed) well is based upon deliverability comparison of the two wells. This paper shows how to describe DWS well deliverability in terms of the top and bottom production rates, water cut, and pressure drawdown. Also, the effect of pressure interference between two well completions on deliverability limits has been studied and qualified experimentally. DWS well deliverability depends on two variables, pressure drawdown and water drainage rate, and is described by a three-dimensional Inflow Performance Domain (IPD). Visual-Basic software based on a new analytical model of IPD has been developed to calculate critical (fluid breakthrough) rates for oil and water. The critical rates identify inflow conditions to the well’s completions—single or two-phase inflow. Also calculated are the values of water cut and maximum pressure drawdown at the well. An example demonstrates the procedure and a complete IPD plot. The experimental study, using a Hele-Shaw physical model of DWS well, demonstrates the reduction of well’s deliverability caused by pressure interference from the second (bottom) completion. The experiments have shown, however, that the deliverability decrease is small and over-compensated by the increase of oil rate due to simultaneous reduction of water cut.

scholarly journals Two-Phase Non-Newtonian Pulsatile Blood Flow Simulations in a Rigid and Flexible Patient-Specific Left Coronary Artery (LCA) Exhibiting Multi-Stenosis

2021 ◽  
Vol 11 (23) ◽  
pp. 11361
Author(s):  
Abdulgaphur Athani ◽  
Nik Nazri Nik Ghazali ◽  
Irfan Anjum Badruddin ◽  
Abdullah Y. Usmani ◽  
Sarfaraz Kamangar ◽  
...  
Keyword(s):  
Blood Flow ◽  
Coronary Artery ◽  
Left Coronary Artery ◽  
Solid Wall ◽  
Three Dimensional ◽  
Patient Specific ◽  
Maximum Pressure ◽  
Three Dimensional Model ◽  
Two Phase ◽  
Pressure Drops

Coronary artery disease (CAD) is stated as one of the most common causes of death all over the world. This article explores the influence of multi stenosis in a flexible and rigid left coronary artery (LCA) model using a multiphase blood flow system which has not yet been studied. Two-way fluid–solid interaction (FSI) is employed to achieve flow within the flexible artery model. A realistic three-dimensional model of multi-stenosed LCA was reconstructed based on computerized tomography (CT) images. The fluid domain was solved using a finite volume-based commercial software (FLUENT 2020). The fluid (blood) and solid (wall) domains were fully coupled by using the ANSYS Fluid-Structure Interaction solver. The maximum pressure drops, and wall shear stress was determined across the sever stenosis (90% AS). The higher region of displacement occurs at the pre-stenosis area compared to the other area of the left coronary artery model. An increase in blood flow velocity across the restricted regions (stenosis) in the LCA was observed, whereas the recirculation zone at the post-stenosis and bifurcation regions was noted. An overestimation of hemodynamic descriptors for the rigid models was found as compared to the FSI models.

Vertical Interference Test in Wells With Downhole Water Sink Completions

2009 ◽  
Vol 131 (3) ◽  
Author(s):  
Ephim Shirman ◽  
Andrew Wojtanowicz
Keyword(s):  
Analysis Method ◽  
Type Curves ◽  
Two Fluids ◽  
Testing Method ◽  
Water Coning ◽  
Interference Test ◽  
Permeability Anisotropy ◽  
Downhole Water Sink ◽  
Well Completions ◽  
Vertical Interference Test

Downhole water sink (DWS) well completions segregate production in the wellbore by producing water from the underlying aquifer and oil—from the oil zone of the reservoir. A pump drains water from the bottom completion to create a pressure drawdown that prevents water from coning up to the top, oil producing zone. Successful application of DWS technology in wells with water-coning problem requires effective isolation between the top and bottom completions of the well. Since DWS technology requires dual completion, the completion is configured for vertical interference testing. The problem is that such test involves flow of two fluids, water and oil. This paper presents a new mathematical model and analysis method for vertical interference testing using top completion (in the oil leg) for production and bottom completion (in the water leg) for observation. The model is analytical and accommodates partial penetration and permeability anisotropy. The analysis method employs a family of type-curves. Examples of possible applications of this new testing method are also shown in this paper.

scholarly journals A new three-dimensional effective water-flooding unit model for potential tapping of remained oil in the reservoirs with rhythmic conditions

2021 ◽  
Vol 11 (3) ◽  
pp. 1375-1391
Author(s):  
Weiyao Zhu ◽  
Cunjia Zou ◽  
Jiulong Wang ◽  
Wenchao Liu ◽  
Jiqiang Wang
Keyword(s):  
Water Injection ◽  
Three Dimensional ◽  
Water Flooding ◽  
Two Phase ◽  
Unit Model ◽  
Vertical Heterogeneity ◽  
Remaining Oil ◽  
Water Cut ◽  
Seepage Channel ◽  
Effective Water

AbstractAfter long-term water injection development, most of the oilfields in China have entered the stage of high-water cut, which has reached up to 90%. Due to the strong heterogeneity of the reservoir, more than 50% of the oil remains underground in most oilfields. Therefore, how to predict the distribution and content of remaining oil quickly and accurately in heterogeneous reservoir has become the key of EOR. In this paper, a new effective water-flooding unit model is established based on a three-dimensional flow function, which can characterize the influence of vertical heterogeneity on flow and the streamline distribution. In addition, two shape functions are defined in the model to characterize the oil–water two-phase flow characteristics in an injection-production unit. The results show that the streamline in the lower part of the positive rhythm reservoir is denser, which leads to the formation of dominant seepage channel with ease. However, for the reverse rhythm reservoir, dominant seepage channel forms in the upper part of the reservoir. Besides, for the two types of reservoirs, the greater the permeability difference is, the faster the water cut increases. Furthermore, under the same rhythm condition, the positive rhythm reservoir reaches 90% water cut half a year earlier than the anti-rhythm reservoir. This study provides new insight and guidance for the development of remaining oil in rhythmic reservoirs.

Assessment and Inclusion of Capillary Pressure/Relative Permeability Hysteresis Effects in Downhole Water Sink (DWS) Well Technology for Water Coning Control

2001 ◽  
Author(s):  
Solomon O. Inikori ◽  
Andrew K. Wojtanowicz
Keyword(s):  
Capillary Pressure ◽  
Relative Permeability ◽  
Oil Production ◽  
Well Performance ◽  
Water Drainage ◽  
Well Design ◽  
Water Coning ◽  
Capillary Pressures ◽  
Reservoir Simulator ◽  
Downhole Water Sink

Abstract The objective of this study is to assess the effects of capillary pressures and relative permeability hysteresis on the performance of wells using the downhole water sink (DWS) technology for water coning control. In the study a commercial reservoir simulator has been adopted to evaluate well performance under conditions of stabilized oil production/water drainage rates for various combinations of these rates. Operational domain of water-free oil production, Inflow Performance Window (IPW), was used to quantify the effects of capillary pressure transition zone and relative permeability hysteresis on the water coning - control performance of DWS wells. Field data from wells in Canada, West Africa and Louisiana exhibiting severe problems of water coning were used in this study. The simulation results show that the basic concept of the DWS is unchanged by the inclusion of capillary pressure and relative permeability hysteresis. However, these effects may cause considerable reduction in the size of the water-free oil production domain and lead to increase in water production. The results also indicate that, for the same reservoir, converting conventional wells with prior water coning history to DWS application would not be as beneficial as DWS completions on new wells. Thus the effect of drainage-imbibition relative permeability hysteresis should be included in the DWS well design practice.

scholarly journals Three-Dimensional Analysis of the In Vivo Motion of Implantable Cardioverter Defibrillator Leads

2021 ◽  
Author(s):  
Tamas Szili-Torok ◽  
Jens Rump ◽  
Torsten Luther ◽  
Sing-Chien Yap
Keyword(s):  
Three Dimensional ◽  
Second Phase ◽  
Two Phase ◽  
Maximum Curvature ◽  
Phase Study ◽  
Absolute Curvature ◽  
Icd Leads ◽  
Lead Testing ◽  
Design And Testing

Abstract Better understanding of the lead curvature, movement and their spatial distribution may be beneficial in developing lead testing methods, guiding implantations and improving life expectancy of implanted leads. Objective The aim of this two-phase study was to develop and test a novel biplane cine-fluoroscopy-based method to evaluate input parameters for bending stress in leads based on their in vivo 3D motion using precisely determined spatial distributions of lead curvatures. Potential tensile, compressive or torque forces were not subjects of this study. Methods A method to measure lead curvature and curvature evolution was initially tested in a phantom study. In the second phase using this model 51 patients with implanted ICD leads were included. A biplane cine-fluoroscopy recording of the intracardiac region of the lead was performed. The lead centerline and its motion were reconstructed in 3D and used to define lead curvature and curvature changes. The maximum absolute curvature Cmax during a cardiac cycle, the maximum curvature amplitude Camp and the maximum curvature Cmax@amp at the location of Camp were calculated. These parameters can be used to characterize fatigue stress in a lead under cyclical bending. Results The medians of Camp and Cmax@amp were 0.18 cm−1 and 0.42 cm−1, respectively. The median location of Cmax was in the atrium whereas the median location of Camp occurred close to where the transit through the tricuspid valve can be assumed. Increased curvatures were found for higher slack grades. Conclusion Our results suggest that reconstruction of 3D ICD lead motion is feasible using biplane cine-fluoroscopy. Lead curvatures can be computed with high accuracy and the results can be implemented to improve lead design and testing.

scholarly journals Investigation of Pressure Oscillation and Cavitation Characteristics for Submerged Self-Resonating Waterjet

2021 ◽  
Vol 11 (15) ◽  
pp. 6972
Author(s):  
Lihua Cui ◽  
Fei Ma ◽  
Tengfei Cai
Keyword(s):  
Sudden Change ◽  
Three Dimensional ◽  
Pressure Oscillation ◽  
Experimental Tests ◽  
Low Pressure ◽  
The Self ◽  
Two Phase ◽  
Cavitation Phenomenon ◽  
Pressure Zone ◽  
Unsteady Characteristics

The cavitation phenomenon of the self-resonating waterjet for the modulation of erosion characteristics is investigated in this paper. A three-dimensional computational fluid dynamics (CFD) model was developed to analyze the unsteady characteristics of the self-resonating jet. The numerical model employs the mixture two-phase model, coupling the realizable turbulence model and Schnerr–Sauer cavitation model. Collected data from experimental tests were used to validate the model. Results of numerical simulations and experimental data frequency bands obtained by the Fast Fourier transform (FFT) method were in very good agreement. For better understanding the physical phenomena, the velocity, the pressure distributions, and the cavitation characteristics were investigated. The obtained results show that the sudden change of the flow velocity at the outlet of the nozzle leads to the forms of the low-pressure zone. When the pressure at the low-pressure zone is lower than the vapor pressure, the cavitation occurs. The flow field structure of the waterjet can be directly perceived through simulation, which can provide theoretical support for realizing the modulation of the erosion characteristics, optimizing nozzle structure.

Analysis of Single- and Two-Phase Flows in Turbopump Inducers

1967 ◽  
Vol 89 (4) ◽  
pp. 577-586 ◽  
Author(s):  
P. Cooper
Keyword(s):  
Equation Of State ◽  
Flow Field ◽  
Thermal Effects ◽  
Single Phase ◽  
Fluid Pressure ◽  
Three Dimensional ◽  
Pressure Rise ◽  
Recent Theory ◽  
Two Phase ◽  
Overall Efficiency

A model is developed for analytically determining pump inducer performance in both the single-phase and cavitating flow regimes. An equation of state for vaporizing flow is used in an approximate, three-dimensional analysis of the flow field. The method accounts for losses and yields internal distributions of fluid pressure, velocity, and density together with the resulting overall efficiency and pressure rise. The results of calculated performance of two sample inducers are presented. Comparison with recent theory for fluid thermal effects on suction head requirements is made with the aid of a resulting dimensionless vaporization parameter.

Thermal Characterization of Interlayer Microfluidic Cooling of Three-Dimensional Integrated Circuits With Nonuniform Heat Flux

2010 ◽  
Vol 132 (4) ◽  
Author(s):  
Yoon Jo Kim ◽  
Yogendra K. Joshi ◽  
Andrei G. Fedorov ◽  
Young-Joon Lee ◽  
Sung-Kyu Lim
Keyword(s):  
Integrated Circuits ◽  
Mass Flow Rate ◽  
Thermal Management ◽  
Mass Flow ◽  
Flow Rate ◽  
Single Phase ◽  
Hot Spot ◽  
Three Dimensional ◽  
Two Phase ◽  
Two Phase Cooling

It is now widely recognized that the three-dimensional (3D) system integration is a key enabling technology to achieve the performance needs of future microprocessor integrated circuits (ICs). To provide modular thermal management in 3D-stacked ICs, the interlayer microfluidic cooling scheme is adopted and analyzed in this study focusing on a single cooling layer performance. The effects of cooling mode (single-phase versus phase-change) and stack/layer geometry on thermal management performance are quantitatively analyzed, and implications on the through-silicon-via scaling and electrical interconnect congestion are discussed. Also, the thermal and hydraulic performance of several two-phase refrigerants is discussed in comparison with single-phase cooling. The results show that the large internal pressure and the pumping pressure drop are significant limiting factors, along with significant mass flow rate maldistribution due to the presence of hot-spots. Nevertheless, two-phase cooling using R123 and R245ca refrigerants yields superior performance to single-phase cooling for the hot-spot fluxes approaching ∼300 W/cm2. In general, a hybrid cooling scheme with a dedicated approach to the hot-spot thermal management should greatly improve the two-phase cooling system performance and reliability by enabling a cooling-load-matched thermal design and by suppressing the mass flow rate maldistribution within the cooling layer.

Development and Validation of a Three-Dimensional Multiphase Flow CFD Analysis for Journal Bearings in Steam and Heavy Duty Gas Turbines

2012 ◽  
Author(s):  
Stephan Uhkoetter ◽  
Stefan aus der Wiesche ◽  
Michael Kursch ◽  
Christian Beck
Keyword(s):  
Experimental Data ◽  
Multiphase Flow ◽  
Gas Turbines ◽  
High Speed ◽  
Three Dimensional ◽  
Air Entrainment ◽  
Journal Bearings ◽  
Heavy Duty ◽  
Present Contribution ◽  
Two Phase

The traditional method for hydrodynamic journal bearing analysis usually applies the lubrication theory based on the Reynolds equation and suitable empirical modifications to cover turbulence, heat transfer, and cavitation. In cases of complex bearing geometries for steam and heavy-duty gas turbines this approach has its obvious restrictions in regard to detail flow recirculation, mixing, mass balance, and filling level phenomena. These limitations could be circumvented by applying a computational fluid dynamics (CFD) approach resting closer to the fundamental physical laws. The present contribution reports about the state of the art of such a fully three-dimensional multiphase-flow CFD approach including cavitation and air entrainment for high-speed turbo-machinery journal bearings. It has been developed and validated using experimental data. Due to the high ambient shear rates in bearings, the multiphase-flow model for journal bearings requires substantial modifications in comparison to common two-phase flow simulations. Based on experimental data, it is found, that particular cavitation phenomena are essential for the understanding of steam and heavy-duty type gas turbine journal bearings.

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