Fully coupled modelling of complex sand controlled completions Michael Byrne
Outline Background Objectives Reservoir, Fluid Properties and Pressure Validating Modelling Fluid Flow Through Inflow Control Device (ICD) Sector Model Geometry and Results Complete Model Geometry and Results Summary
1385m 1717m 1737m 1808.4m 2195.1m 2502.9m 2595.8m 2619.1m 2737.7m Typical Sector 1 set-up, 1000 s of Perforations Background Well Length = 1352.7m Split into 4 Completion sections and 8 Reservoir sectors 9-5/8 40# Casing, 12spf 5-1/2 SAS 9-5/8 40# Casing and 7 29# Casing 6-5/8 SAS 5-1/2 SAS Sector 1: To Be Recompleted 332m Sector 4 386.7m Sector 5 307.8m Sector 8 118.6m Sector 1 Reservoir B1 Sand (10D) Annular Perm 5D Completion 9-5/8 40# Cased + Perf 5-1/2 SAS + ICD Sector 2 20m Completion 9-5/8 40# Casing Sector 3 71.4m Completion 7 29# Casing Sector 4 Reservoir B1 Sand (10D) Annular Perm 5D Completion 9 Open Hole 1 port 33 x 6-5/8 SAS (1 SP) Sector 5 Reservoir A3 Sand (2D) Annular Perm 1D Completion 9 Open Hole 1 x 6-5/8 SAS (1 SP) 10 port Crossover 25 x 5-1/2 SAS (1 SP) 10 port Sector 6 92.9m Reservoir B1 Sand (10D) Annular Perm 5D Completion 9 Open Hole 8 x 5-1/2 SAS (1 SP) 1 port Sector 7 23.3m Reservoir A3 Sand (2D) Annular Perm 1D Completion 9 Open Hole 2 x 5-1/2 SAS (1SP) 1 port Sector 8 Reservoir A3 Sand (2D) Annular Perm 1D Completion 9 Open Hole 9 x 5-1/2 SAS (1SP) 10 port2 Sector 1 B1 Sand Sector 4 B1 Sand Sector 5 A3 Sand Sector 6 B1 Sand Sectors 7 + 8 A3 Sand
Objectives The modeling was undertaken with the following objectives: 1. To determine if addition of a new cased and perforated interval would improve well oil productivity and retain production from original open hole section. 2. To quantify the productivity of 12 shots per foot (spf) vs 6 spf vs OH options. (The open hole option here is included merely as a benchmark). 3. To determine the productivity of the cased and perforated interval when connected to the existing open hole section.
Reservoir, Fluid Physical Properties and Pressure Reservoir Section Length (m) Completion Type Fluid No of ICDs and SAS No of ICD Ports Open Reservoir Permeability (md) Annulus Permeability (md) S01 332 12 SPF Oil 28 10 10,000 5,000 S02 20 Casing Shoe N/A N/A N/A N/A N/A S03 71.4 Casing Shoe N/A N/A N/A N/A N/A S04 386.7 Open Hole Water 31 1 10,000 12.15 S05 307.8 Open Hole Water 26 10 2,000 2.45 S06 92.9 Open Hole Water 8 1 10,000 12.15 S07 23.3 Open Hole Water 2 1 2,000 2.45 S08 118.6 Open Hole Water 9 10 2,000 2.45 Fluid Property Vermillion Oil Vermillion Water Density (kg/m 3 ) 889 1,016 Viscosity (cp) 15.0 0.6 Reservoir Pressure (psi) 783 OH Bottom Hole Flow Pressure (psi) 682 C&P Bottom Hole Flow Pressure (psi) 673
Validating Fluid Flow Through Inflow Control Device (ICD) ICD open nozzles 10 Ports ICD open nozzles 10 Ports CFD Modelling
Pressure Drop Across ICD (psi) Pressure Drop Across ICD (psi) Validating Fluid Flow Through Inflow Control Device (ICD) 300 250 200 1 Port Open Actual 1 Port Open CFD Pressure Drop Across ICD 150 100 50 Pressure Drop for1 Port Open, 50 bpd of water: from 30 psi to 14 psi (16 psi pressure drop) Excellent Correlation Between CFD Pressure Drop and Measured Pressure Drop 0 40 60 80 100 120 140 160 180 200 Water Volume Flow Rate (bpd) 100 80 60 40 20 2 Port Open Actual 2 Port Open CFD Pressure Drop Across ICD 0 40 60 80 100 120 140 160 180 200 Oil Volume Flow Rate (bpd)
Open Hole Sector Model (1 Joint ~ 39 ft Long) Geometry Reservoir Drainage Layer ICD Wellbore Annulus Drainage Layer Length Detail Completion Modelling
C & P 6 spf Sector Model (1 Joint ~ 39 ft Long) Geometry Detail Completion Modelling
C & P 12 spf Sector Model (1 Joint ~ 39 ft Long) Geometry Detailed Completion Modelling
Pressure (psi) Pressure Drop Calculation Pressure Drop 160 140 120 100 80 60 10 Darcy Permeability 40 20 0 Reservoir Inlet Wellbore Inlet MicroAnnulus Inlet Drain Holes Inlet The major pressure loss component in the system is at the ICD, proving that the ICD is the dominant factor that influences the fluid inflow into the well
Volume Flow Rate (bbl/day) Inflow Performance Comparison Comparison of Inflow Performance 1400 1200 130 psi (local) Pressure Draw Down 1000 800 600 400 200 0 Open Hole 12SPF 6SPF The C & P configuration introduces further restriction (pressure drop) hence less flow rate The ICD in all three cases had 10 ports open to minimize its influence.
Volume Flow Rate (bbl/day) Productivity Index Inflow Performance Against Drawdown 700 600 500 400 300 6 SPF 12SPF Linear (6 SPF) Linear (12SPF) y = 4.278x + 32.994 y = 2.7065x + 13.626 200 100 0 0 20 40 60 80 100 120 140 (Local) Pressure Draw Down (psi) For the 12 spf configuration, increasing the drawdown results in higher inflow compared to the 6 spf configuration hence higher Productivity Index 12 spf is to be used for the complete model
Toe Heel C&P Completion Flow Structure Near the Wellbore Insignificant pressure drop from reservoir to wellbore annulus away from the ICD and drainage layer ~ No inflow away from the drainage layer
The Complete Geometry: 12 spf C&P coupled to OH Completion 332 m of 12 SPF C&P 28 x Stand Alone Screen (SAS), 28 x Inflow Control Device (ICD) More than 10,000 Perforations 930 m of OH 76 x Stand Alone Screen (SAS), 76 x Inflow Control Device (ICD) Over 500 million cells For multiphase runs up to 30,000 iterations Using 1024 parallel cores...48 hours to convergence
Volume Flow Rate (bpd) Water Production; OH Completion On Its Own OH Completion Only 4,500 4,000 2 D Permeability 10 ICD Port Open 307.8 m long 3,500 3,000 2,500 2,000 1,500 1,000 500 0 10 D Permeability 1 ICD Port Open 386.7 m long 10 D Permeability 1 ICD Port Open 92.9 m long S04 OH Only S05 OH Only S06 OH Only S07 OH Only S08 OH Only Reservoir Section 2 D Permeability 1 ICD Port Open 23.3 m long 10 D Permeability 10 ICD Port Open 118.6 m long S04 OH Only S05 OH Only S06 OH Only S07 OH Only S08 OH Only Section S05, despite having lower reservoir permeability and shorter length than the section S04, produces most of the water, due to all 10 ICD ports being open, compared to just 1 port being open on the S04 section; indicating that the ICD is the dominant factor to control the flow rate
Volume Flow Rate (bpd) Water and Oil Production; Coupled C&P and OH 16,000 Water & Oil Volume Flow Rate 14,000 12,000 10,000 8,000 6,000 13,801 14,667 4,000 2,000 8,333 6,976 0 Water: OH Only Water: C&P + OH Oil: C&P + OH Oil: C&P Only When the C&P recompletion section is connected to the existing OH completion, there is reduction in both the water and oil production compared to OH and C&P on their own This is expected as the water and oil flow would work against each other, and it suggests the importance of modelling the entire well as one system
The 1 st ICD in the C&P Section Flow Structure Around the ICD and the Tubing Outlet A cross section through the 1 st ICD in the C&P Section Red : 100% Oil Blue : 100% Water Tubing Outlet ICD Near the Heel
Summary A complex numerical challenge was solved using CFD and HPC Addition of the new completion will improve well productivity and still preserve drainage from the open hole section The sector model sensitivity runs proved that the perforations located away from the drainage layer of the screens had minimal contribution to the well s productivity The sector models also proved that in terms of productivity, the OH ranked the best followed by the 12spf and 6spf completion ICD is the dominant factor in controlling the flow rate There is a considerable importance to model the C&P well and the OH well as one fully connected system
Slide 20 Acknowledgements Dr. Lesmana Djayapertapa, Ken Watson, Senergy Barry Goodin, Vermilion Oil & Gas Australia Pty Ltd Ken Ichihashi for his significant contribution in the early stages of this study Vermillion and Senergy Management for permission to publish this material Thank You Any Questions?