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Reservoir EngineeringPermeability and Flow

Normalized Saturation Formula

Son=1SwSor1SwiSorS_{on}=\frac{1-S_w-S_{or}}{1-S_{wi}-S_{or}}

Normalized Saturation calculates normalized saturation for permeability and flow workflows in reservoir engineering.

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How engineers use this formula

Use this formula when the listed inputs (S_w, S_or, S_wi) are known and the assumptions behind the cited permeability and flow relationship match the engineering case being checked.

Assumptions

  • Input values are representative for the well, reservoir, fluid, or equipment case being evaluated.
  • The declared units match the field-unit constants used in the formula.
  • The cited formula applies to the selected petroleum engineering workflow.

Limitations

  • The calculation does not replace a full engineering model or operating procedure.
  • Accuracy depends on the source correlation, assumptions, input quality, and unit consistency.

Common mistakes

  • Mixing unit systems without converting the inputs.
  • Using default example values as field recommendations.
  • Applying the formula outside the source assumptions.

Default example

Using the default inputs, S_on equals 0.833333 fraction.

S_wfraction

0.3

S_orfraction

0.2

S_wifraction

0.2

Inputs

S_w

fraction

Water Saturation

S_or

fraction

Residual Oil Saturation

S_wi

fraction

Initial Water Saturation

Outputs

S_on

fraction

Normalized Saturation

S_w

fraction

Water Saturation

S_or

fraction

Residual Oil Saturation

S_wi

fraction

Initial Water Saturation

Source and review

reviewed

Wikipedia.org.

Source

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