Turner Critical Gas Rate for Liquid Loading Formula
Turner Critical Gas Rate for Liquid Loading calculates critical gas rate for well performance workflows in production engineering.
How engineers use this formula
Use this formula when the listed inputs (P_wh_abs, T_R, rho_L, sigma_l, gamma_g, z, D_i) are known and the assumptions behind the cited well performance relationship match the engineering case being checked.
Assumptions
- Input values are representative for the well, reservoir, fluid, or equipment case being evaluated.
- The declared units match the field-unit constants used in the formula.
- The cited formula applies to the selected petroleum engineering workflow.
Limitations
- The calculation does not replace a full engineering model or operating procedure.
- Accuracy depends on the source correlation, assumptions, input quality, and unit consistency.
Common mistakes
- Mixing unit systems without converting the inputs.
- Using default example values as field recommendations.
- Applying the formula outside the source assumptions.
Default example
Using the default inputs, q_gc equals 0.578199 MMscf/day.
400
580
67
60
0.6
0.9
1.995
Inputs
P_wh_abs
psiaFlowing Wellhead Pressure
T_R
degRFlowing Wellhead Temperature
rho_L
lbm/ft3Liquid Density
sigma_l
dyne/cmLiquid Surface Tension
gamma_g
dimensionlessGas Specific Gravity
z
dimensionlessGas Compressibility Factor
D_i
inTubing Inside Diameter
Outputs
q_gc
Critical Gas Rate
v_gc
Turner Critical Gas Velocity
rho_g
Gas Density at Wellhead Conditions
A_t
Tubing Flow Area
Source and review
reviewedTurner et al. 1969 critical velocity correlation; Pengtools liquid-loading workflow and Cranfield liquid-loading review.
Source