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Separator Minimum Diameter from Gas Capacity Formula

Dmin=4qaπFGVGmaxD_{min}=\sqrt{\frac{4q_a}{\pi F_GV_{Gmax}}}

Separator Minimum Diameter from Gas Capacity calculates minimum separator inside diameter for well performance workflows in production engineering.

Calculate

How engineers use this formula

Use this formula when the listed inputs (q_a, F_G, V_Gmax) 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, D_min equals 2.888901 ft.

q_aft3/s

10

F_Gfraction

1

V_Gmaxft/s

1.5256146302392357

Inputs

q_a

ft3/s

Actual Gas Flow Rate at Separator Conditions

F_G

fraction

Fraction of Vessel Cross-Section Available for Gas Flow

V_Gmax

ft/s

Maximum Allowable Superficial Gas Velocity

Outputs

D_min

ft

Minimum Separator Inside Diameter

q_a

ft3/s

Actual Gas Flow Rate at Separator Conditions

F_G

fraction

Fraction of Vessel Cross-Section Available for Gas Flow

V_Gmax

ft/s

Maximum Allowable Superficial Gas Velocity

Source and review

reviewed

John M. Campbell / PetroSkills. Gas-Liquid Separators Sizing Parameter.

Source

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