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Development of COMSOL-based applications for heavy oil reservoir modelling
S. Cambon(1) – I. Bogdanov(1) – A. Godard(2)
October 15th, 2015
(1) Open & Experimental Centre for Heavy Oil, University of Pau, Pau, France
(2) Jean Féger’s Scientific & Technical Centre, TOTAL S.A., Pau, France
Industrial challenge – Heavy oil reserves
2
Huge potential - around 500 billion barrels
- almost double Saudi Arabia’s reserves
(greatest volume of conventional oil)
Growing energy needs - extend the world’s energy reserves by
15 years
Significant challenges - only 3% are produced or under active
development
Oil sands and Bitumen (our interest)
- specific gravity from 7 to 9 °API
- viscosity of up to 10.000 cP Source: TOTAL website www.total.com
This unconventional oil is
becoming essential
so viscous that they are
non-mobile
… but …
Sébastien CAMBON - COMSOL Conference Grenoble 2015
Existing recovery technologies
3
Source: TOTAL website www.total.com
In-situ cold production - for low mobility, a diluent is injected
and production is made by depletion
Open-pit mining - effective for non-mobile oil but feasible
only if depth is lower than 100 meters
Thermal recovery (our interest) - Requires an input of energy to reduce
the viscosity and so increase mobility
(most widely used: SAGD, CSS)
SAGD: Steam Assisted Gravity Drainage
CSS: Cyclic Stream Stimulation
For deep non-mobile reserves, only thermal recovery can be applied
highly increases the production cost
Sébastien CAMBON - COMSOL Conference Grenoble 2015
Thermal enhanced oil recovery (EOR)
4
Oil sands and Bitumen Mobile oil
1
10
100
1000
10000
100000
1000000
10000000
0 50 100 150 200 250 300
Oil
vis
co
sit
y c
P
Temperature °C
°API<10 and viscosity up
to 10.000 cP
°API>20 and viscosity
lower than 100 cP Heating effect
Can be combined with conventional recovery techniques
Production is therefore feasible but as complex as costly
Energy efficiency becomes a key factor
Sébastien CAMBON - COMSOL Conference Grenoble 2015
Electromagnetic heating technology
5 Sébastien CAMBON - COMSOL Conference Grenoble 2015
Transmission lines
EM. antennas
Production well
Objectives
(1) Limit transmission lines loss
(2) In-situ generate heating power
(3) Create and extend steam chamber
Water vaporization open a way to heat deeper in the reservoir
Works at low reservoir pressure (contrary to SAGD)
Vaporization depends on the working pressure
Example of studied pattern
PROS & CONTRAS
6
PROS
Avoids injectivity problem (EHO deposits)
Removes heat loss from well (cf. SAGD)
In-situ heats a reservoir and can generate steam
Reduces environmental impact (opposed to mining)
CONTRAS
Exhibits energy loss in transmission line
Production efficiency and economics to be improved
Technology is still not mature
Further research necessary to improve both
energy efficiency and recovery factor
Require an accurate and efficient simulator
Sébastien CAMBON - COMSOL Conference Grenoble 2015
A multi-physics problem
Several kind of physics:
Multiphase flow in porous media
Phase transition
Heat transfer
Electromagnetic field
7
How to solve that problem ?
Sébastien CAMBON - COMSOL Conference Grenoble 2015
A multi-physics problem
Several kind of physics:
Multiphase flow in porous media
Phase transition
Heat transfer
Electromagnetic field
8
How to solve that problem ?
Accurate numerical methods
Take into account all the physics
Interface is easy to handle
Too consuming at reservoir scale
Not a reservoir simulator !
First idea
using only COMSOL Multiphysics ?
Sébastien CAMBON - COMSOL Conference Grenoble 2015
A multi-physics problem
Several kind of physics:
Multiphase flow in porous media
Phase transition
Heat transfer
Electromagnetic field
9
How to solve that problem ?
Accurate numerical methods
Take into account all the physics
Interface is easy to handle
Too consuming at reservoir scale
Not a reservoir simulator !
More than 50 years of research
Efficient at reservoir scale
Suited to complex fluid composition
Not adapted to EM. field simulation
First idea
using only COMSOL Multiphysics ?
Second idea
using only reservoir simulator ?
Sébastien CAMBON - COMSOL Conference Grenoble 2015
A multi-physics problem
Several kind of physics:
Multiphase flow in porous media
Phase transition
Heat transfer
Electromagnetic field
10
How to solve that problem ?
First idea
using only COMSOL Multiphysics ?
Second idea
using only reservoir simulator ?
Sébastien CAMBON - COMSOL Conference Grenoble 2015
An innovative idea
To couple both simulator together !
EMIR – ElectroMagnetism Interacting with Reservoir
EMIR - Loose coupling approach
11 11 Sébastien CAMBON - COMSOL Conference Grenoble 2015
Coupling foundations
1. Reservoir simulator only requires a global heating energy estimation 𝑃𝑤 in J/day at each
coupling time and for each reservoir grid blocks
2. Time-harmonic electromagnetic propagation
Restrictions (example in 2D)
The reservoir part of the electromagnetic mesh must be a sub-mesh of the reservoir grid
Reservoir grid (CMG-STARS)
Electromagnetic mesh (COMSOL)
Not allowed (too complex) Naturally usable
𝑃𝑤 𝑀 = 𝑄 𝑥, 𝑦, 𝑧 𝑑𝑒𝑒∩𝑀𝑒∈𝐸ℎ
𝑒∩𝑀≠∅
EMIR - Algorithm
12 12
Reservoir
simulation
start
Reservoir
simulation
finished
EMIR
EMIR time step
EMIR EMIR EMIR EMIR EMIR
0 1 2 n-2 n-1 n
Reservoir sub-time
step
time
EMIR computes physical
parameters
COMSOL computes EM fields
EMIR retrieves heating power
STARS updates
evolution JAVA API
EMIR
Sébastien CAMBON - COMSOL Conference Grenoble 2015
13
Reservoir simulator grid
20 m
Vertical antenna integration (simplified design)
COMSOL Multiphysics grid
Sébastien CAMBON - COMSOL Conference Grenoble 2015
EMIR – Example “Dipole antenna”
Antenna design efficiently made in COMSOL (not possible in STARS)
Matching between both grids easily controlled by the JAVA API
Antenna internal heating is not handled in the reservoir simulation
Air
Glass
Dipole
conductor
Steel
Power supply
𝑷𝒘
EM. window
EM model - performance
Around 950 coupling time-steps (step average 1.5 days)
COMSOL requires almost 4 minutes to solve each coupling time-step
Solver: PARDISO (shared memory parallelization)
Number of threads: 16 (one cluster node fully used)
Reservoir grid blocks: almost 350 000
Required days of computation for 3D models
14 Sébastien CAMBON - COMSOL Conference Grenoble 2015
Simulation period: almost 4 years & Input power: 120 kW
0
10
20
30
40
50
60
70
80
0 90 180 270 360 450 540 630 720 810 900 990 1080 1170 1260 1350 1440 1530
Cu
mu
late
d c
om
pu
tati
on
al T
ime
(h)
COMSOL
STARS
INTEGRATION
REPORT
Total time ≈ 135 hours
15
EM model - results
Sébastien CAMBON - COMSOL Conference Grenoble 2015
Conclusions
16
EMIR is an innovative tool for petroleum industries
Prove its operational applicability to 2D and 3D problems
Extend reservoir simulation capabilities to direct EM applications
COMSOL successfully provides a way to couple powerful simulators together
Java API is really easy to handle
If needed, adding new dedicated petroleum (or not) simulator is still possible
Sébastien CAMBON - COMSOL Conference Grenoble 2015
Future works
Evaluate the distributed memory solver “MUMPS” on several cluster nodes
Couple the RF module with the AC/DC one to model an antenna tuner
Use COMSOL “If+End If” feature to optimize the computational domain along time
17
Thank you for your attention
Sébastien CAMBON - COMSOL Conference Grenoble 2015
Acknowledgment
TOTAL S. A is gratefully acknowledged for sponsoring the research work of the
Open & Experimental Centre for Heavy Oil (CHLOE)