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Shape Factor Expressed as Skin Factor for Vertical Wells Formula

sCA=ln[(31.62CA)0.5]s_{CA}=\ln\left[\left(\frac{31.62}{C_A}\right)^{0.5}\right]

Shape Factor Expressed as Skin Factor for Vertical Wells calculates shape-related skin factor for well performance workflows in production engineering.

Calculate

How engineers use this formula

Use this formula when the listed inputs (C_A) 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, s_CA equals 0.026296 dimensionless.

C_Adimensionless

30

Inputs

C_A

dimensionless

Shape Factor

Outputs

s_CA

dimensionless

Shape-Related Skin Factor

C_A

dimensionless

Shape Factor

Source and review

reviewed

Joshi, S.D. 1991. Horizontal Well Technology, Chapter 7, Page 208.

Source

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