Production EngineeringWell Performance
API RP 14E Gas-Liquid Mixture Density Formula
API RP 14E Gas-Liquid Mixture Density calculates gas-liquid mixture density for well performance workflows in production engineering.
How engineers use this formula
Use this formula when the listed inputs (S_L, P, R, S_g, T, Z) 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, rho_m equals 12.291613 lb/ft3.
S_Lspecific gravity
1.0470588235294118
Ppsia
1615
Rscf/bbl
5882.35294117647
S_gspecific gravity
0.66
TdegR
580
Zdimensionless
0.81
Inputs
S_L
specific gravityAverage Liquid Specific Gravity
P
psiaOperating Pressure
R
scf/bblGas-Liquid Ratio
S_g
specific gravityGas Specific Gravity
T
degROperating Temperature
Z
dimensionlessGas Compressibility Factor
Outputs
rho_m
lb/ft3
Gas-Liquid Mixture Density
Source and review
reviewedReview of the API RP 14E erosional velocity equation, Eq. 2 mixture-density form.
SourceRelated formulas and calculators
Effective Wellbore Radius of a Well in Presence of Uniform Flux Fractures
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Effective Wellbore Radius of a Horizontal Well – Method 1 (Anisotropic Reservoirs)
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Effective Wellbore Radius of a Horizontal Well – van der Vlis et al. Method
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