Well drawn down pressure
Moderator: Simulation_team
Well drawn down pressure
Having no experience in practical reservoir simulation I have a question.
The description
I have a gas reservoir with a very strong aquifer support. I have two wells in the reservoir. Now I am producing them at a rate of
WELDRAW
--Name Max P drawdown Phase
P1 4 GAS YES MAX/
P2 30 GAS YES MAX/
/
My
WCONPROD
'P1' 'OPEN' 'GRAT' 2* 40000/
'P2' 'OPEN' 'GRAT' 2* 40000/
/
My reservoir depletes very very fast. In 200 days I have aquifer influx. The reason I am producing at such a high rate in p2 is that I need to shit it at a certain water cut and inject polymers to it.
That is at a later stage, but as of now can you help me out with my problem of the aquifer influx which is too fast.
Regards
Tejaswy
The description
I have a gas reservoir with a very strong aquifer support. I have two wells in the reservoir. Now I am producing them at a rate of
WELDRAW
--Name Max P drawdown Phase
P1 4 GAS YES MAX/
P2 30 GAS YES MAX/
/
My
WCONPROD
'P1' 'OPEN' 'GRAT' 2* 40000/
'P2' 'OPEN' 'GRAT' 2* 40000/
/
My reservoir depletes very very fast. In 200 days I have aquifer influx. The reason I am producing at such a high rate in p2 is that I need to shit it at a certain water cut and inject polymers to it.
That is at a later stage, but as of now can you help me out with my problem of the aquifer influx which is too fast.
Regards
Tejaswy
-
Abdelkader
- Junior member
- Posts: 72
- Joined: Thu Aug 31, 2006 7:33 am
- Location: algiers
Tejaswy,
try to check the permeability you imposed perhaps it's too high and so makes the influx come preferentially to P2 rather than a balance between your 2 wells!
Another point would be the draw down you are choosing t produce your well, try to comment it and let the software compute the THP using the VFPs of the wells!
Cheers,
Abdelkader
try to check the permeability you imposed perhaps it's too high and so makes the influx come preferentially to P2 rather than a balance between your 2 wells!
Another point would be the draw down you are choosing t produce your well, try to comment it and let the software compute the THP using the VFPs of the wells!
Cheers,
Abdelkader
Thank you for you excellent suggestion. Yes my permeability is indeed very high,250md in y direction. I really cannot change that.....Or may be I can. I will let you know. I need some aquifer fingering in it. I other wise had a piston like push
I do no know how this can be done. Can you give an example please ?Another point would be the draw down you are choosing t produce your well, try to comment it and let the software compute the THP using the VFPs of the wells!
Cheers,
-
Abdelkader
- Junior member
- Posts: 72
- Joined: Thu Aug 31, 2006 7:33 am
- Location: algiers
Tejaswy
what I meant was to let the software control the THP, I guess you are using a VFP table for the well to account for the completions of the wells and the pressure loss along the tubing, this is done by an export from Prosper check that also!
regarding the Y perm of corse you can modify it but using perm modifiers multiplyers using MULTIPLY key word or WPIMULT check both in the manual!
always keep the Manual open it's the most valuable source of information and don't go for short-cuts, read the description of the keyword till the example!
keep us informed of your evolution!
regards,
Abdelkader
what I meant was to let the software control the THP, I guess you are using a VFP table for the well to account for the completions of the wells and the pressure loss along the tubing, this is done by an export from Prosper check that also!
regarding the Y perm of corse you can modify it but using perm modifiers multiplyers using MULTIPLY key word or WPIMULT check both in the manual!
always keep the Manual open it's the most valuable source of information and don't go for short-cuts, read the description of the keyword till the example!
keep us informed of your evolution!
regards,
Abdelkader
NO, I do not have any VFP or THP for the wells. No completions nothing. Just a gas reservoir with two wells in eclipse producing at a constant gas rate from all the layers.
I have reduced the permeability considerably. I have to keep the Perm Y a little higher than Perm x as it is a up dip reservoir and I need a fingering movement in it.
I have reduced the permeability considerably. I have to keep the Perm Y a little higher than Perm x as it is a up dip reservoir and I need a fingering movement in it.
-
Abdelkader
- Junior member
- Posts: 72
- Joined: Thu Aug 31, 2006 7:33 am
- Location: algiers
Tejaswy,
would you mind to explain me how you could produce from a well (I mean in the simulation) without using a VFP table?! if you are a Prosper user you already know that we need to generate IPR/VLP curves to compute extrapolate the production rates and their relation to the Tubing head pressure (or BHP either) it is the so called Nodal Analysis.
As the IPR (Inflow Performance Relationship) is directly related to the Reservoir (Skin, KH Pres) and the VLP (Vertical Lift Performance) that represents the pressure drop along the tubing which depends on the ID of the tubing, the nature of the fluids in place (Multiphase flow) and the Delta between the BHP and the WHP.
Having said this, you could imagine that the cross point between the two curves will give you the actual working point (that we usually want to be as accurate as any separator test or field test result) as you enter the measured (real data) and you want to match it with your curve.
Regarding the permeability, you should also affect or act on your vertical perm (to account for heterogeneity) usually as a Rule of Thumb we just take the 10th of Kx or Ky so Kz=Kx/10.
Hope it'll help you figure out what is going on!
Regards,
Abdelkader
would you mind to explain me how you could produce from a well (I mean in the simulation) without using a VFP table?! if you are a Prosper user you already know that we need to generate IPR/VLP curves to compute extrapolate the production rates and their relation to the Tubing head pressure (or BHP either) it is the so called Nodal Analysis.
As the IPR (Inflow Performance Relationship) is directly related to the Reservoir (Skin, KH Pres) and the VLP (Vertical Lift Performance) that represents the pressure drop along the tubing which depends on the ID of the tubing, the nature of the fluids in place (Multiphase flow) and the Delta between the BHP and the WHP.
Having said this, you could imagine that the cross point between the two curves will give you the actual working point (that we usually want to be as accurate as any separator test or field test result) as you enter the measured (real data) and you want to match it with your curve.
Regarding the permeability, you should also affect or act on your vertical perm (to account for heterogeneity) usually as a Rule of Thumb we just take the 10th of Kx or Ky so Kz=Kx/10.
Hope it'll help you figure out what is going on!
Regards,
Abdelkader
I think we are missing something here.
Here is a screenshot of the reservoir
Am I missing something here ?
I have done nodal analysis using "pipesim" VLP and THP, IPR OPR but I don't think that they are need here...are they.?
I understand that VLP, IPR and THP are important in production history and data matching But i don't think that they have anything to do with defining a simulation case.
I am just trying to show a increase in gas recovery with injection in polymers in the gas reservoir.
I am still new to eclipse so...
Here is a screenshot of the reservoir
Am I missing something here ?
I have done nodal analysis using "pipesim" VLP and THP, IPR OPR but I don't think that they are need here...are they.?
I understand that VLP, IPR and THP are important in production history and data matching But i don't think that they have anything to do with defining a simulation case.
I am just trying to show a increase in gas recovery with injection in polymers in the gas reservoir.
I am still new to eclipse so...
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