Page 145 - Formulas and Calculations for Petroleum Engineering

138 Formulas and calculations for petroleum engineering

Output(s)

V r : Required Volume of water/diesel/any liq (bbl)

Formula(s)

W W 2
1
V ¼ V
r m
W D
2 w
Reference: Formulas and Calculations for Drilling, Production and Workover, Second Edition, Lapeyrouse, Page: 85.

2.151 Mudcake growth equation—Formation invasion

Input(s)
f s : Mud Solid Fraction (fraction)
Ø c : Mudcake Porosity (fraction)
v N : Darcy Velocity of the Filtrate through the cake and past the paper (in./s)

Output(s)
dx c tðÞ : Mudcake Growth by time (in./s)
dt

Formula(s)

!
dx tðÞ f s
c
v

¼ n
dt 1 f ð 1 Ø Þ
s
c
Reference: Chin, W. C. (1995). Formation Invasion, Page: 39.
2.152 Mudcake growth equation-2—Formation invasion
Input(s)
Ø eff : Effective Porosity (fraction)
f s : Mud Solid Fraction (fraction)
Ø c : Mudcake Porosity (fraction)
x f : Transient Invasion Front (in.)
x f, o : Initial Displacement, i.e., Spurt (in.)

Output(s)

x c (t): Mudcake Growth by time (in./s)

Formula(s)

h i

x tðÞ ¼ Ø f = 1 Ø Þ 1 f x x
ð
c eff s c s f f,o
Reference: Chin, W. C. (1995). Formation Invasion, Page: 45.