Page 66 - Formulas and Calculations for Petroleum Engineering

Reservoir engineering formulas and calculations Chapter 1 59

1.135 Underground fluid withdrawal—Havlena and Odeh

Input(s)
G p : Cumulative Gas Production (SCF)
B g : Gas Formation Volume Factor (bbl/SCF)
W p : Cumulative Water Production (STB)
B w : Water Formation Volume Factor (bbl/STB)

Output(s)
F: Fluid Withdrawal (bbl)

Formula(s)

F ¼ G B +W B
p g p w

Reference: Ahmed, T., McKinney, P.D. 2005. Advanced Reservoir Engineering, Gulf Publishing of Elsevier, Chapter: 3,
Page: 259.

1.136 Vertical well critical rate correlations—Craft and Hawkins method
Input(s)

b: Penetration Ratio, (h p /h) (dimensionless)
r e : Radius of Drainage (ft)
r w : Radius of Wellbore (ft)
h p : Thickness of Perforated interval (ft)
h: Oil Column Thickness (ft)
m o : Oil Viscosity (cP)
B o : Oil Formation Volume Factor (RB/STB)
k o : Effective Oil Permeability (mD)
p ws : Static Well Pressure Corrected to the Middle of the Producing Interval (psi)
p wf : Flowing Well Pressure at the Middle of the Producing Interval (psi)

Output(s)

PR: Productivity Ratio (dimensionless)
q o : Critical Rate (Maximum Oil Rate without Coning) (STB/day)

Formula(s)

r w

0:5
PR ¼ b 1+ 7 cos b 90°ð Þ
2 b h

0:007078 k h p p wf
ws
o
q ¼ PR
o
r
m B ln e
o o
r
w
Reference: Joshi, S. D. 1991, Horizontal Well Technology. Tulsa, Oklahoma: PennWell Publishing Company. Chapter: 8,
Page: 254.