Page 238 - Petroleum Production Engineering, A Computer-Assisted Approach

Guo, Boyun / Computer Assited Petroleum Production Engg 0750682701_chap15 Final Proof page 236 22.12.2006 6:14pm

15/236 PRODUCTION ENHANCEMENT

Temperature
Noise Amplitude
> 600 Hz

Gas
zone

Gas
Gas
Oil
Oil
production Oil
zone

Figure 15.12 Temperature and noise logs identifying gas channeling behind casing (Economides et al., 1994).

Depth Temperature ( F)
Fluid density (g/cc)

A

B
C

D

Figure 15.13 Temperature and fluid density logs identifying a gas entry zone (Economides et al., 1994).

p ffiffiffiffiffiffiffiffiffi
E ksl ¼ 0:04 sr L : (15:27) droplets from falling) plus the transport velocity of the
In gas wells producing water, typical values for water–gas droplets, that is,
interfacial tension and water density are 60 dynes/cm and v gm ¼ v sl þ v tr : (15:28)
3
65 lb m =ft , respectively. This yields the minimum kinetic
3
energy value of 2:5lb f -ft=ft . In gas wells producing conden- The transport velocity v tr may be calculated on the
sate, typical values for condensate–gas interfacial tension basis of liquid production rate, geometry of the conduit,
3
and condensate density are 20 dynes/cm and 45 lb m =ft , and liquid volume fraction, which is difficult to quantify.
respectively. This yields the minimum kinetic energy value Instead of trying to formulate an expression for
3
of 1:2lb f -ft=ft . the transport velocity v tr , Guo et al. used v tr as an empir-
The minimum gas velocity required for transporting the ical constant to lump the effects of nonstagnation ve-
liquid droplets upward is equal to the minimum gas ve- locity, drag coefficients for solid spheres, and the critical
locity required for floating the liquid droplets (keeping the Weber number established for drops falling in air. On the