This document provides an overview of CMG reservoir simulation software. It describes the main CMG components, including BUILDER for model creation, IMEX for black oil simulation, GEM for compositional simulation, STARS for thermal and advanced processes, and CMOST for history matching and optimization. It also outlines the typical workflow, from model construction in BUILDER, running the simulators, and using RESULTS for post-processing. Key applications are highlighted for each simulator, such as primary/secondary recovery for IMEX, compositional and thermal EOR processes for GEM and STARS.

1. CMG | Reservoir Simulator
Soran University - Faculty of Petroleum Engineering -
Reservoir Simulation - 4th Stage
Prepared by: Anas Razaq; Rawa Sarbaz; Rahel Abdurrahman; Mohammed Omer;
Goran Mohammed | GROUP A
Supervised by: Mr. Sarkar M. Hama; Ms. Fenk A. Sulaiman
2023 - 2024

2. Outli
ne
 Computer Modelling Group Ltd. | CMG Software
 CMG Components
 CMG workflow
 CMG Overview
 Simulator Data Organization
 Phase Behaviour & Fluid Property Program
 Builder
 IMEX
 GEM
 STARS
 CMOST
 Result
 Key Steps in a Simulation Study
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3. CMG Software
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4. CMG Software
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5. LAUNCHER = File Management & Job Scheduling
BUILDER = Simulation Model Creation/Editing
WINPROP = PVT Phase Behavior Characterization
IMEX = 3-phase, 4-components Black Oil Simulator
GEM = 3-phase, n-component EOS Compositional Simulator
STARS = 4-phase, n-component Thermal/CEOR Simulator
CMOST = History Matching, Optimization, Sensitivity & Uncertainty Analysis
COFLOW= Integrated Production & Reservoir Simulation
RESULTS = X-Y Plots, Grid Visualization & Data Extraction
CMG Components
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6. CMG workflow
Pre-Processing Post-Processing
Simulator
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7. CMG Overview
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8. .Results – Template file for post processing in Results software
Basic file extensions
.dat - Simulator input file that contains all information that
simulator requires to perform its flow calculations
.inc - Additional input files referred to in .dat file
.fhf - Historical data can be stored in this file type
out - File output by the simulator containing information
on the model in ASCII text
.sr3 - Binary file containing the simulator results
Simulator Data Organization
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9. Phase Behaviour & Fluid Property Program
Phase Behaviour Modelling & PVT Creation using WinProp
•Characterize the heavy fraction of the petroleum fluids
•Lump and split components
•Match laboratory PVT data through regression
•Simulate first and multiple contact miscibilities
•Perform multiphase equilibrium calculations
•Perform phase diagram generation
Laboratory Results Output of Winprop
• “Black-oil” PVT description (IMEX)
• EOS PVT description (GEM)
• K value PVT description (STARS)
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10. Builder
• User Interface for preparing reservoir simulation models
• Use BUILDER to construct IMEX, GEM and STARS datasets
Builder Sections
I/O Control: Simulation or text results output, Restart, etc.
Reservoir: Grid structure, properties, etc.
Components: Fluid model
Rock-Fluid: Relative permeability, capillary pressure, etc.
Initial Conditions: Initial pressure/saturations, Pb, etc.
Numerical: Convergence criteria, explicit/implicit, etc.
Geomechanics (optional): Stress dependent properties, etc.
Wells & Recurrent: Well trajectories, perforations, constraints, etc.
Builder
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11. Builder
Geomodel: Create in Builder
Builder integrates all the static and dynamic properties to construct a reservoir model
• Use BUILDER to CONSTRUCT IMEX, GEM and STARS datasets
• Use BUILDER to CONVERT IMEX to GEM and STARS
Builder can handle two different approaches for PVT modelling:
• Laboratory Results ( Winprop)
Typically include composition and experiments
• Limited data (Correlations)
Basic information related to gas and oil densities, Saturation Pressure and Reservoir
Temperature is required
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12. Simulators
Generalized Equation-of-State Model Reservoir Simulator (GEM)
• GEM is a full equation-of-state compositional reservoir simulator with advanced features for modelling
recovery processes where the fluid composition affects recovery.
• GEM also models asphaltenes, coal bed methane and the geochemistry of the sequestration of various gases
including acid Gases and CO2.
IMplicit-EXplicit Black Oil Simulator (IMEX)
• IMEX is a full -featured three-phase, four-component black oil reservoir simulator for modelling
primary depletion and secondary recovery processes in conventional oil and gas reservoirs.
• IMEX also models pseudo-miscible and polymer injection in conventional oil reservoirs, and
primary depletion of gas condensate reservoirs, as well as the behavior of naturally or
hydraulically fractured reservoirs.
Steam, Thermal andAdvanced processes Reservoir Simulator (STARS)
• STARS is a thermal, K-value compositional, chemical reaction and geomechanics reservoir
simulator ideally suited for advanced modelling of recovery processes involving the injection of
steam, solvents, air and chemicals.
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13. IMEX
Applications
Black Oil & Unconventional Simulator
IMEX models primary and secondary oil recovery processes in conventional and
unconventional reservoirs.
 Primary recovery
Black Oil & Volatile Oil
Dry & Wet Gas
Gas Condensate
 Secondary recovery
Waterflooding
Polymer Flooding
Dry Gas Injection
Pseudo-miscible Displacement
 Gas Storage
Abandoned Gas Fields
Aquifer Storage
 Naturally Fractured Reservoirs
Gas Oil Gravity Drainage (GOGD)
 Explicit Modelling of Hydraulically fractured wells
with non-Darcy flow and Compaction
IMEX
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14. IMEX
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15. IMEX
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16. IMEX
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17. IMEX
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18. GEM
Applications
Compositional &Unconventional Simulator
GEM is the world-leading Equation-of-State (EoS) reservoir simulator for
compositional, chemical and unconventional reservoir modelling.
 Secondary Recovery
Miscible & Immiscible gas injection (CO2, N2, Sour Gas, Flue Gas) in
Continuous, WAG and SWAG modes
Gas condensate production with dry/lean gas cycling to recover liquids
VAPEX heavy oil recovery (isothermal and thermal)
 CBM & Shale Gas Production
Multi-component desorption/adsorption, diffusion & coal
swelling/shrinkage
 Gas Storage
Abandoned Oil Reservoirs (to model light oil/condensate recovery)
Tracking gas composition
CO2 & Acid Gas Sequestration
Oil reservoirs, Saline aquifers & Coal beds (ECBM)
Geochemical reactions
GEM
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19. GEM
Applications
Asphaltene modelling during primary and secondary recovery
Precipitation, Flocculation, Deposition & Plugging
Naturally Fractured Reservoirs
Gas Oil Gravity Drainage (GOGD) in naturally fractured reservoirs
CBM & Shale Reservoirs
Explicit Modelling of Hydraulically fractured wells with non-Darcy flow &
Compaction
Single Plane Fractures (Vertical & Horizontal Wells in Tight reservoirs)
Complex Fracture Networks ( Vertical & Horizontal Wells in Shale
reservoirs)
Coupled Surface Facilities
Branched surface networks using hydraulics tables and FORGAS
Looped surface networks coupled to GAP and PIPEPHASE
Coupled Geomechanics
GEOMECH
GEM
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20. STARS
Applications
Thermal & Advanced Process Simulator
STARS is the undisputed industry standard for the advanced modelling of recovery
processes involving steam, solvents, air and chemicals.
Thermal EOR
Hot water flooding
Steam flooding & Cyclic Steam Stimulation
SAGD & ES-SAGD
In-Situ Combustion (LTO & HTO)
In-Situ Conversion of Oil Shale (Shell ISC process)
Chemical EOR
Emulsions, Gels, Foams
ASP
, SP
, ASG (foam surfactant)
MEOR
LoSAL waterflooding
Brightwater polymer flooding
Gas Storage
Salt Cavern Storage
STARS
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21. STARS
Applications
Naturally Fractured Reservoirs
Steam Oil Gravity Drainage (SOGD) in naturally fractured reservoirs
Cold Heavy Oil Recovery (CHOPS model built with AITF)
Natural Gas Hydrates
Geothermal
Complex Thermal Wellbore Completions
Discretized Wells (transient, segregated flow of steam, oil, gas &
water in single tubing horizontal wells)
FlexWells (transient, segregated flow of steam, oil, gas & water in
multiple tubing, undulating wells)
Coupled Surface Facilities
PIPEPHASE
Coupled Geomechanics
GEOMECH
STARS
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22. Intelligent Optimization & Analysis Tool
CMOST
• Use AI and Machine Learning
with human expertise to
identify optimal solutions
• Data driven proxies allow for
quick and interactive “what if ”
analysis
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23. RESULTS
• Automatic Repeat Plots
• Analyze 2D and 3D results together in one window
• Reporting
Post-Processor: Visualization & Analysis
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24. Key Steps in a Simulation Study
Reservoir
Characterization
Model Selection
Model Construction
Model Validation
Predictions
Documentation
Compare & Adjust
History Macthing
with CMOST
Construct model
with BUILDER
RESULTS
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25. Thank you
Any Questions?
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26. References:
• https://www.cmgl.ca/
• https://www.cmgl.ca/events
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