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Required Water Section Length in Separator Formula

Lw=twqwAwL_w=\frac{t_wq_w}{A_w}

Required Water Section Length in Separator calculates required water section length for well performance workflows in production engineering.

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How engineers use this formula

Use this formula when the listed inputs (t_w, q_w, A_w) 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, L_w equals 2 ft.

t_wmin

12

q_wft3/min

2

A_wft2

12

Inputs

t_w

min

Water Residence Time

q_w

ft3/min

Water Volumetric Flow Rate

A_w

ft2

Water Flow Area

Outputs

L_w

ft

Required Water Section Length

t_w

min

Water Residence Time

q_w

ft3/min

Water Volumetric Flow Rate

A_w

ft2

Water Flow Area

Source and review

reviewed

John M. Campbell. 1992. Gas Conditioning and Processing, Campbell Petroleum Series, Oklahoma, Vol. 2, Page 80.

Source

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