Well test beginner question(2)

[mohammed105]

what kind of K(permeability) obtained from well test???
absolute or effective

[Chee Koh Peh]

You should only have single phase flow in your welltests if you plan to interpret them using analytical techniques. If you have mutilphase flow you require numerical techniques to analyse the welltest due to the relative permeability effects. Effective permeability is a measurement in a multiphase flow situation.. Thus you are measuring the absolute permeability provided you are in single phase flow i.e. testing above the bubble point. You are measuring relative permeability testing below the bubble point when in multiphase flow as both the gas and oil phases are present.

[mohammed105]

Thanks Chee Koh Peh

[manish.7417@gmail.com]

what kind of K(permeability) obtained from well test???
absolute or effective

Permeability obtained from Well Test is termed as Dynamic Equivalent Liquid Permeability which is coming from Middle Time Region i.e. Where Radial flow is obtained.

[mohammed105]

Dear manish7417,
can you explain it easier,plz

[mohamed_B]

the measured permeability by well test is the effective permeability.

[dhiaa12]

effective permeability one gets from well test

[arashrabiei]

the absolute permeability is defined when there is only one fluid available in the media, and as we have different fluids such as water, oil and free gas we have relative permeability concept. so in fact we have relative permeability, and even when we have connate water we have relative permeability at end point saturation (e.g. sw=swc).
the permeability which obtained from the core analysis is a local permeability and we can't extension that permeability to the whole reservoir ,but in well testing we get total permeability which give an overall permeability that include matrix and fracture permeability ( overall permeability ) in the well drainage which our test can investigate. so this permeability can represent the actual permeability of the reservoir rock better.
it should be noted that during well testing when we have 2 phases flow the interpretation would change.

[awaadalkh]

friend
the K obtained from well test analysis is the effective K

[braindrain]

Which permeability is mos reliable for dynamic modeling Permeability obtain from core analysis and from well test permeability.

please let me clear... If any literature available please give me....


thanks..!

[mohamed_B]

Hey, Can we interpret a build up test without the presence of a draw down test before, I mean no draw down test was carried out before the shut in of the well.

[arashrabiei-PUT]

usually they do both of the tests for confirmation, i mean the results from both of the tests should be consistent. but if you just want to use Build up test , the duration which the well produce is important (tp). while production time usually is so much longer than shut in time so in this case the exact amount of tp is not necessary .