Water moving at its connate saturation value

[DAH7542]

Dear Vinomarky and 06pg22,

Taking a look at the provided data set (EPS.DATA) some questions and comments arised:

1. To 06pg22 and vinomarky: according to SWOF table, water is mobile at Sw = 0.295 (as vinomarky said), this means Swir = 0.24, at this point Kro = 0.784; howerver 06pg22 has one more Sw value below Swir (where Kro = 1), how can this be?, going back in time, if oil migrated into the reservoir it could only be able to displaced water at a minimum Sw = 0.24. Connate water sat could be greater than Irreducible water saturation, but could connate water sat be lower than Swir ?

2. To 06pg22 and vinomarky: following point #1 takes me to the second question, how can Kro be greater than Kro at Swir ?, in the provided SWOF table Kro at Swir = 0.784 but there is an additional value of Kro = 1.0.

3. To 06pg22: I'm not pretty sure by taking a look at your SWOF table of what your reference permeability is, I'm sure it's not Ko at Swir, so it should be Ko at Sw = 15% because you have Kro = 1 at Sw = 15%, but this takes me again to questions #1 and #2.

4. To 06pg22 and vinomarky: I use to adding an extra value of Krw = 1.0 at Sw = 100% (extra data point in SWOF table) to reproduce flow within water zone, which is 100% water saturated so effective perm equals absolute perm (using this one as a reference); the provided data set has Krw = 0.7 at Sw = 100%, which is not consistent with what I explained here, why is that?

Thanks in advanced for clarifying this doubts, it'll be interesting to discuss this topics....

[vinomarky]

1. To 06pg22 and vinomarky: according to SWOF table, water is mobile at Sw = 0.295 (as vinomarky said), this means Swir = 0.24, at this point Kro = 0.784; howerver 06pg22 has one more Sw value below Swir (where Kro = 1), how can this be?, going back in time, if oil migrated into the reservoir it could only be able to displaced water at a minimum Sw = 0.24. Connate water sat could be greater than Irreducible water saturation, but could connate water sat be lower than Swir ?

Not exactly - you can't take the rel perm table built to describe imbibition process under project execution timeframes and categorically state it is wrong because when extending it to geological timeframes and drainage scenarios it doesn't work. As constructed, it simply means that a given grid block at 0.15 Sw initially needs to increase to a Sw of 0.24 before any water will flow out of it (under reasonable timeframe), and that during the increase in water saturation oil is flowing out. This is the difference between the connate water (SWL) and the critical water saturation (SWCR) - have a read of the saturation scaling section of the Eclipse Technical manual

2. To 06pg22 and vinomarky: following point #1 takes me to the second question, how can Kro be greater than Kro at Swir ?, in the provided SWOF table Kro at Swir = 0.784 but there is an additional value of Kro = 1.0.

Per above, it's not - SWL = 0.15, Kromax = 1.0

4. To 06pg22 and vinomarky: I use to adding an extra value of Krw = 1.0 at Sw = 100% (extra data point in SWOF table) to reproduce flow within water zone, which is 100% water saturated so effective perm equals absolute perm (using this one as a reference); the provided data set has Krw = 0.7 at Sw = 100%, which is not consistent with what I explained here, why is that?

Here I would agree - generally the Krw at Sw=1.0 (ie in Aquifer) should be unity, and the Kro at SWL should be at or (more normally) something less than unity. If you take a look at the sheet I put togeather at

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