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Real Gas Pseudopressure Difference for Constant Mu-Z Calculator

Δm=p22p12μgz\Delta m=\frac{p_2^2-p_1^2}{\mu_g z}

Enter the required inputs, confirm the units, and run the calculator to solve Delta_m. Review the formula source and assumptions before using the result in engineering work.

Tabular solver

Inputs

Defaults provide a quick field-unit example for the equation.

4 variables

Your input values and calculation stay in this browser.

Engineering reference summary

Calculation context and source notes

Real Gas Pseudopressure Difference for Constant Mu-Z calculates real gas pseudopressure difference for gas properties workflows in phase behavior and thermodynamics. The page keeps the declared variables, units, source relationship, and output definition visible for technical review.

Use this formula when the listed inputs (p_1, p_2, mu_g, z) are known and the assumptions behind the cited gas properties relationship match the engineering case being checked.

Solves for

Delta_m (psi^2/cp)

Formula reference

Formula, variables, and default calculation

Δm=p22p12μgz\Delta m=\frac{p_2^2-p_1^2}{\mu_g z}

Reproducible default result

With the default values shown below, the calculation returns Delta_m = 470,588,235.294118 psi^2/cp. Defaults demonstrate the implementation; they are not recommended field values.

p_1psia

1000

p_2psia

3000

mu_gcp

0.02

zdimensionless

0.85

Input definitions

p_1

psia

Lower Pressure

p_2

psia

Upper Pressure

mu_g

cp

Gas Viscosity

z

dimensionless

Gas Compressibility Factor

Output definitions

Delta_m

psi^2/cp

Real Gas Pseudopressure Difference

p_2

psia

Upper Pressure

p_1

psia

Lower Pressure

mu_g

cp

Gas Viscosity

z

dimensionless

Gas Compressibility Factor

Engineering use, assumptions, and limits

Use this formula when the listed inputs (p_1, p_2, mu_g, z) are known and the assumptions behind the cited gas properties 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.

Frequently asked questions

What inputs does the Real Gas Pseudopressure Difference for Constant Mu-Z calculator need?

The calculation uses Lower Pressure (p_1), Upper Pressure (p_2), Gas Viscosity (mu_g), Gas Compressibility Factor (z). Enter values on the units shown beside each field.

What result does this calculator return?

The primary result is real gas pseudopressure difference in psi^2/cp. The formula section shows the declared relationship, variables, and a reproducible default calculation.

What should I check before using the result?

Confirm the unit basis, source applicability, and input quality. The calculation does not replace a full engineering model or operating procedure. Mixing unit systems without converting the inputs.

Source and record status

Source metadata identifies the relationship implemented by the calculator. Check the cited edition, unit basis, and scope against the engineering case before operational use.

reviewedguidance published

Gas permeability measurements from pressure pulse decay laboratory data using pseudo-pressure and pseudo-time transformations, Abdelmalek, B. et al.

Abdelmalek et al. 2017. Gas permeability measurements from pressure pulse decay laboratory data using pseudo-pressure and pseudo-time transformations.

Open source reference

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