Page 74 - Formulas and Calculations for Petroleum Engineering

Reservoir engineering formulas and calculations Chapter 1 67

Output(s)

W: Water Content (fraction)

Formula(s)

W ¼ y Whc + yco Wco + yhs Whs

Reference: Campbell, J. M., (1992, Houston, TX (United States)), Gas Conditioning and Processing, Vol. 1, Campbell
Petroleum Series, Page: 149.

1.154 Water cut—Stiles

Input(s)
k: Permeability (mD)
h: Cumulative Thickness for Breakthrough Layer & Above (ft)
M wo : Mobility Ratio (fraction)
k t : Cumulative Flow Capacity for Breakthrough Layer & Above (mD ft)
h t : Cumulative Flow Capacity for the Whole Model (mD ft)

Output(s)
f w : Water Cut (fraction)

Formula(s)

k h M wo
f ¼
w
k h M + k h k h
wo t t
Reference: Ehrlich, R. 2016. Enhanced Oil Recovery, Lecture Notes.

1.155 Water-drive index for gas reservoirs

Input(s)
W e : Cumulative Water Influx (bbl)
W p : Cumulative Water Production (bbl)
B w : Water Formation Volume Factor (rb/STB)
G p : Cumulative Gas Production at Depletion Pressure (MSCF)
B g : Gas Formation Volume Factor at Depletion Pressure (bbl/SCF)

Output(s)
WDI: Water Drive Index (dimensionless)

Formula(s)

W W B w
e
p
WDI ¼
G B
p g
Reference: Ahmed, T., McKinney, P.D. 2005. Advanced Reservoir Engineering, Gulf Publishing of Elsevier, Chapter: 3,
Page: 211.