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Production EngineeringWell Performance

Newton Law Droplet Settling Velocity Formula

Vt=1.74gDp(ρpρc)ρcV_t=1.74\sqrt{\frac{gD_p(\rho_p-\rho_c)}{\rho_c}}

Newton Law Droplet Settling Velocity calculates terminal droplet settling velocity for well performance workflows in production engineering.

Calculate

How engineers use this formula

Use this formula when the listed inputs (g, D_p, rho_p, rho_c) 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, V_t equals 2.074883 m/s.

gm/s2

9.80665

D_pm

0.005

rho_pkg/m3

900

rho_ckg/m3

30

Inputs

g

m/s2

Gravitational Acceleration

D_p

m

Droplet Diameter

rho_p

kg/m3

Droplet Phase Density

rho_c

kg/m3

Continuous Phase Density

Outputs

V_t

m/s

Terminal Droplet Settling Velocity

D_p

m

Droplet Diameter

rho_p

kg/m3

Droplet Phase Density

rho_c

kg/m3

Continuous Phase Density

g

m/s2

Gravitational Acceleration

Source and review

reviewed

GPSA Engineering Data Book, Section 7 Separation Equipment, Eq. 7-8.

Source

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