Page 44 - Formulas and Calculations for Petroleum Engineering

Reservoir engineering formulas and calculations Chapter 1 37

Output(s)

k: Permeability (mD)

Formula(s)

3 2
B Ø d
k ¼
τ
Reference: Mark D. Zoback, Reservoir Geomechanics, Cambridge University Express, UK, Page: 41.

1.84 Leverett J-function

Input(s)
2
s: Fluid interfacial tension (dyn/cm )
y: Angle of wettability (fraction)
Pc: Capillary Pressure (dyn/cm)
k: Permeability (mD)
ø: Porosity (fraction)

Output(s)

J: Leverett J-function (dimensionless)

Formula(s)

0:5
Pc k

J ¼
s cos yðÞ ø
Reference: Reservoir Engineering Handbook, Fourth Edition, Ahmed, Page: 224.

1.85 Line-source solution for damaged or stimulated wells

Input(s)
P i : Initial Pressure (psi)
t: Time of production (h)
k: Permeability (mD)
B: Volume factor (RB/STB)
Ø: Porosity (fraction)
c t : Compressibility (1/psi)
h: Thickness of reservoir (ft)
m: Viscosity of Oil (cP)
r: Radius of wellbore (ft)
q: Flow Rate (STB/day)
s: Skin Factor (dimensionless)

Output(s)

P wf : Line-Source Solution for Damaged or Stimulated Wells (psi)