Page 253 - Formulas and Calculations for Petroleum Engineering

246 Formulas and calculations for petroleum engineering

4.92 Temperature at choke outlet

Input(s)
T u : Upstream Temperature (R)
z u : Z Factor of Upstream Gas Flow (dimensionless)
z o : Z Factor of Upstream Gas Flow in Outlet (dimensionless)
k: Specific Heat Ratio (dimensionless)
P o : Outlet Pressure (psi)
P u : Upstream Pressure at Choke (psi)

Output(s)
T dn : Downstream Temperature (R)

Formula(s)

k 1

z u P o k
T ¼ T
dn u
z P
o u
Reference: Boyun, G., William, C., & Ali Ghalambor, G. (2007). Petroleum Production Engineering: A Computer-Assisted
Approach, Page: 5/62.

4.93 The z component of the force of the fluid on the wetted surface of the pipe

Input(s)
po: Pressure at initial point (Pa)
pL: Pressure at point L (Pa)
R: Radius (m)
L: Length (m)
3
ρ: Density (kg/m )
2
g: Gravitational Acceleration (m/s )
Output(s)

Fz: z-Component of Force (Newton)

Formula(s)

2 2
Fz ¼ π R po pLð Þ + π R L ρ g

Reference: Transport Phenomena, Second Edition, Bird, Page: 51.

4.94 Total skin in partially depleted wells for a buildup test
Input(s)

r ew : Dimensionless Parameter in terms of Perforated Length and Wellbore Radius (dimensionless)
ø: Porosity (fraction)
μ: Viscosity (cP)
c t : Total Compressibility (1/psi)
k: Permeability (mD)