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Reservoir EngineeringFluid Flow in Porous Media

Darcy's Law for Linear Single-Phase Flow Formula

q=0.001127kAΔPμLq = \frac{0.001127 k A \Delta P}{\mu L}

Darcy's Law for Linear Single-Phase Flow calculates volumetric flow rate for fluid flow in porous media workflows in reservoir engineering.

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How engineers use this formula

Use this formula when the listed inputs (k, A, DeltaP, mu, L) are known and the assumptions behind the cited fluid flow in porous media 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 equals 2.8175 bbl/day.

kmD

100

Aft²

500

DeltaPpsi

100

mucP

2

Lft

1000

Inputs

k

mD

Permeability

A

ft²

Cross-Sectional Flow Area

DeltaP

psi

Pressure Drop

mu

cP

Fluid Viscosity

L

ft

Flow Length

Outputs

q

bbl/day

Volumetric Flow Rate

k

mD

Permeability

A

ft²

Cross-Sectional Flow Area

DeltaP

psi

Pressure Drop

mu

cP

Fluid Viscosity

L

ft

Flow Length

Source and review

reviewed

Lyons, W.C. 2010. Working Guide to Reservoir Engineering. Darcy equation discussion.

Source

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