History Matching in Eclipse

All Reservoir Simulation aspects

Moderator: Simulation_team

User avatar
FANARCO
Administrator
Administrator
Posts: 2063
Joined: Mon Jul 10, 2006 9:56 pm
Contact:

Re: History Matching in Eclipse

Post by FANARCO »

Important to know which variables may have a significant effect on the history match and which may not.

Thus, at the beginning of the history matching process a sensitivity analysis of the key parameters is suggested.
User avatar
FANARCO
Administrator
Administrator
Posts: 2063
Joined: Mon Jul 10, 2006 9:56 pm
Contact:

Re: History Matching in Eclipse

Post by FANARCO »

Before starting to history match: define the data to be matched and the tolerances.

Final Match tolerances depend on:


- The study objectives
- The data quality
- The model coarseness
- Time and money available History





.
User avatar
FANARCO
Administrator
Administrator
Posts: 2063
Joined: Mon Jul 10, 2006 9:56 pm
Contact:

Re: History Matching in Eclipse

Post by FANARCO »

There are no “hard and fast” rules for history matching.

However, the following may be of some help:

- Keep it simple (KISS)
- Keep it physical
- Use common sense
- Don’t panic!
- Run model under voidage control until pressures matched, then switch to principal product rate
- Proper use of pseudos is more consistent than rock curves
- Correct the problem, not the symptom
- The most difficult problems may require a rethink of the base data
User avatar
FANARCO
Administrator
Administrator
Posts: 2063
Joined: Mon Jul 10, 2006 9:56 pm
Contact:

Re: History Matching in Eclipse

Post by FANARCO »

Pressure match


- Run the model under reservoir voidage control

- Examine the overall pressure levels, adjust the pore volume/aquifer properties to match overall pressure

- Match the well pressures, modify local PVs/aquifers to match overall pressures; modify local transmissibility to match pressure gradient








.
engrsajid
Posts: 21
Joined: Sun Feb 09, 2014 10:31 am
Location: pakistan
Contact:

Re: History Matching in Eclipse

Post by engrsajid »

thanks alot sir very useful post for new beginners
User avatar
FANARCO
Administrator
Administrator
Posts: 2063
Joined: Mon Jul 10, 2006 9:56 pm
Contact:

Re: History Matching in Eclipse

Post by FANARCO »

engrsajid wrote:thanks alot sir very useful post for new beginners

Thanks sajid,

We will continue.....
User avatar
FANARCO
Administrator
Administrator
Posts: 2063
Joined: Mon Jul 10, 2006 9:56 pm
Contact:

Re: History Matching in Eclipse

Post by FANARCO »

Saturation match


- Normally attempted once pressures matched
- Most important parameters are rel. perm. curves and permeabilities
- Try to explain the reasons for the deviations and act accordingly
- Changes to rel. perm. tables should affect the model globally
- Changes to permeabilities should have some physical justification
- Consider the use of well pseudos
- Assumed layer KH allocations may be incorrect (check PLTs, etc.)






.
User avatar
FANARCO
Administrator
Administrator
Posts: 2063
Joined: Mon Jul 10, 2006 9:56 pm
Contact:

Re: History Matching in Eclipse

Post by FANARCO »

Well PI match

- Not usually matched until pressures and saturations are matched, unless BHP affects production rates

- Must be matched before using model in prediction mode

- Match FBHP data by modifying KH, skin or PI directly
User avatar
FANARCO
Administrator
Administrator
Posts: 2063
Joined: Mon Jul 10, 2006 9:56 pm
Contact:

Re: History Matching in Eclipse

Post by FANARCO »

Automatic history matching does not exist. New Eclipse SimOpt program is a history matching aid.


Try to minimize an objective function over the time period of the history:

Image
User avatar
FANARCO
Administrator
Administrator
Posts: 2063
Joined: Mon Jul 10, 2006 9:56 pm
Contact:

Re: History Matching in Eclipse

Post by FANARCO »

History Matching Adjustments


Simulation field pressure too high

Image

Possible Changes


Pore Volume?
Aquifer?
Oil Initially in Place
(Contacts, So)
Energy?
Gas cap size








..
User avatar
FANARCO
Administrator
Administrator
Posts: 2063
Joined: Mon Jul 10, 2006 9:56 pm
Contact:

Re: History Matching in Eclipse

Post by FANARCO »

Break Through: OK, After BT WC too high

Image


Possible Changes



Krw / Kro ratio decrease?
Aquifer size?







..
User avatar
FANARCO
Administrator
Administrator
Posts: 2063
Joined: Mon Jul 10, 2006 9:56 pm
Contact:

Re: History Matching in Eclipse

Post by FANARCO »

Water BT too early, After BT slope - OK

Image


Possible Changes


Effective end point Krw ?
Horiz. Permeability of well to aquifer layer?
Shale or barrier between wells and water?
Vertical permeability between wells and water?
Numerical dispersion / grid effect?








..
User avatar
FANARCO
Administrator
Administrator
Posts: 2063
Joined: Mon Jul 10, 2006 9:56 pm
Contact:

Re: History Matching in Eclipse

Post by FANARCO »

Gas BT simulation very late, After BT slope OK


Image


Possible Changes



Effective Krg end point?
Shale or barrier effecting coning?
Vertical permeability between wells and gas?
Numerical dispersion / grid effect?







..
User avatar
FANARCO
Administrator
Administrator
Posts: 2063
Joined: Mon Jul 10, 2006 9:56 pm
Contact:

Re: History Matching in Eclipse

Post by FANARCO »

Gas BT OK, After BT simulation slope in error


Image


Possible Changes

Krg / Kro ratio increase?
Supply of gas?







.
User avatar
FANARCO
Administrator
Administrator
Posts: 2063
Joined: Mon Jul 10, 2006 9:56 pm
Contact:

Re: History Matching in Eclipse

Post by FANARCO »

Predictions


Most simulation models are used to produce production forecasts. Exact details of prediction cases depend on particular field, so difficult to generalize.


- During predictions, well rates usually controlled primarily by FTHP/FBHP

- Most simulators can model a wide variety of operating constraints

- Check that the transition from “history” to “prediction” is smooth

- Monitor carefully “automatic” workovers

- Take care when using the model to plan infill drilling

- Simulation model recoveries are usually optimistic




..
Post Reply