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Reservoir EngineeringWaterflooding and EOR

Water Cut - Stiles Formula

fw=khMwokhMwo+kthtkhf_w=\frac{khM_{wo}}{khM_{wo}+k_th_t-kh}

Water Cut - Stiles calculates water cut for waterflooding and eor workflows in reservoir engineering.

Calculate

How engineers use this formula

Use this formula when the listed inputs (k, h, M_wo, k_t, h_t) are known and the assumptions behind the cited waterflooding and eor 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, f_w equals 0.421053 fraction.

kmD

100

hft

20

M_wofraction

2

k_tmD

150

h_tft

50

Inputs

k

mD

Breakthrough-Layer Permeability

h

ft

Cumulative Thickness for Breakthrough Layer and Above

M_wo

fraction

Water-Oil Mobility Ratio

k_t

mD

Average Permeability for the Whole Model

h_t

ft

Total Model Thickness

Outputs

f_w

fraction

Water Cut

M_wo

fraction

Water-Oil Mobility Ratio

k

mD

Breakthrough-Layer Permeability

h

ft

Cumulative Thickness for Breakthrough Layer and Above

k_t

mD

Average Permeability for the Whole Model

h_t

ft

Total Model Thickness

Source and review

reviewed

Enhanced Oil Recovery, Ehrlich, R. (2016)

Ehrlich, R. 2016. Enhanced Oil Recovery, Lecture Notes.

source conflict
Source

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