Weber Number Calculator

Engineering calculator reviewed for preliminary design use · Last updated: March 2026

Calculate Weber number We = ρv²L/σ. Apply to droplet breakup, bubble formation, and mist generation analysis. Use for spray nozzle design and gas-liquid contactor evaluation.

What this calculator is used for

The Weber number compares inertial forces to surface tension forces and is used to assess droplet and bubble stability in multiphase systems.

Typical engineering use cases

  • Spray and atomization analysis
  • Gas-liquid contact equipment screening

Governing equation and methodology

We = ρ · v² · L / σ

Engineering assumptions and limitations

  • Representative characteristic length

Practical design notes

Weber number should be reviewed alongside Reynolds and Froude numbers to understand interfacial behavior.

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Frequently Asked Questions

What does Weber number predict?

We = ρv²L/σ predicts whether a droplet or jet will remain intact or break up. High We (>12 for droplets) indicates breakup is likely. Low We means surface tension holds the droplet together.

How is Weber number used in spray design?

In spray nozzle design, We determines the droplet size distribution. Higher We at the nozzle exit produces finer droplets. It also affects spray penetration distance and evaporation rate.

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Editorial Responsibility
  • Last reviewed: March 2026
  • Reviewed by: EngiCompute Editorial Team
  • Intended for preliminary engineering use

These results are preliminary estimates for screening-level design use. They do not replace detailed engineering, code compliance verification, or vendor-certified calculations.