Page 113 - Formulas and Calculations for Petroleum Engineering
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106 Formulas and calculations for petroleum engineering
Formula(s)
r ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi
n o
2
1
x tðÞ ¼ H + H +2 Hx + ⁄2x 2 + Gt
f f,o f,o
( )
m k k 1 eff s
n o. Ø f
o 1
G ¼ k p pð Þ=m Ø
1 m r f eff
m k k ð 1 Ø Þ 1 f
f 3 2 c s
" # ( )
x Ø f m k L . m k k Ø f
f ,o eff s o 1 o 1 1 eff s
H ¼
ð 1 Ø Þ 1 f m k m k k ð 1 Ø Þ 1 f
c s f 3 f 3 2 c s
Reference: Chin, W. C. (1995). Formation Invasion, Page: 16.
2.73 Effective weight during drilling
Input(s)
w s : Weight of Drillstring Material (lbs)
r o : Density of Mud (ppg)
r s : Density of Drillstring Material (ppg)
Output(s)
w o : Effective Weight (lbs)
Formula(s)
r o
w ¼ w 1
s
o
r s
Reference: Samuel. E Robello. 501 Solved Problems and Calculations for Drilling Operations. Sigma Quadrant. 2015.
Houston, Texas, Page: 26.
2.74 Effective wellbore radius for finite-conductivity fractures
Input(s)
k f : Fracture Conductivity (mD)
b f : Fracture Width (ft)
k: Formation Conductivity (mD)
x f : Fracture Half Length (ft)
Output(s)
F CD : Dimensionless Fracture Conductivity (dimensionless)
r w : Effective Wellbore Radius (ft)
