Page 194 - Formulas and Calculations for Petroleum Engineering

Well test analysis formulas and calculations Chapter 3 187

Formula(s)

0 1

B C
A 2:2458
B C
P ¼ 2 p t DA +0:5 ln B ! C +0:5 ln +0:5 2:77
D
L Ah
B 2 C C
@ A
4
2
Reference: Joshi, S. D. 1991, Horizontal Well Technology. Tulsa, Oklahoma: PennWell Publishing Company. Chapter: 7,
Page: 216.
3.26 Dimensionless production time

Input(s)
t D : Dimensionless time (dimensionless)
2
A: Drainage Area (m )
r w : Well Radius (m)

Output(s)
t DA : Dimensionless Production time (dimensionless)

Formula(s)

r 2 w
t ¼ t
DA D
A
Reference: Ramey Jr., H. J. (1981). Reservoir Engineering Assessment of Geothermal Systems. Department of Petroleum
Engineering, Stanford University, Page: (5.7).

3.27 Dimensionless rate (radial flow/constant pressure production)
Input(s)

p i : Initial Reservoir Pressure (psi)
q: Flow Rate (STB/day)
B: Formation Volume Factor (RB/STB)
m: Oil Viscosity (cP)
k: Permeability (mD)
h: Reservoir Thickness (ft)
p wf : Well Flowing Pressure (psi)

Output(s)

q d : Dimensionless Rate (dimensionless)

Formula(s)

q B m
q ¼
d
0:00708 k h p p
i wf
Reference: Lee, J., Rollins, J. B., & Spivey, J. P. (2003). Pressure Transient Testing (Vol. 9). Richardson, Texas: Society of
Petroleum Engineers, Page: 9.