Weber Number Calculator
Ratio of inertia to surface tension — governs droplet breakup and atomization.
We ≈ 12 is the classic critical Weber number for bag breakup of a falling drop — central to spray-nozzle and irrigation design.
Formula
Weber Number Calculator is a free weber number for process, mechanical and water engineers — instant, accurate and 100% client-side, with the governing formula and reference shown next to the result so the number can be defended, not just quoted.
About Weber Number Calculator
Ratio of inertia to surface tension — governs droplet breakup and atomization. The calculation implements We = ρ·V²·L / σ (Lefebvre & McDonell, Atomization and Sprays). We ≈ 12 is the classic critical Weber number for bag breakup of a falling drop — central to spray-nozzle and irrigation design.
How to use Weber Number Calculator
- 1Enter Fluid density in kg/m³.
- 2Enter Characteristic velocity in m/s.
- 3Enter Characteristic length (droplet/jet dia) in mm.
- 4Enter Surface tension σ in mN/m (Water–air 20 °C = 72.8).
- 5Read Weber number instantly — no submit button needed.
- 6Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Weber Number Calculator?
- ✓Implements the standard formula — We = ρ·V²·L / σ
- ✓Reference cited on-page: Lefebvre & McDonell, Atomization and Sprays
- ✓One-click SI ⇄ Imperial toggle — values convert in place, physics stays in SI
- ✓Live worked example: the substitution recomputes from your numbers
- ✓Built-in engineering verdict flags out-of-range results instantly
- ✓Runs entirely in your browser — nothing uploaded, free forever
Frequently asked questions
What formula does the Weber Number Calculator use?+
It computes We = ρ·V²·L / σ, per Lefebvre & McDonell, Atomization and Sprays. The formula is displayed under the result along with a worked example substituted with your own inputs.
What should I keep in mind when using this calculator?+
We ≈ 12 is the classic critical Weber number for bag breakup of a falling drop — central to spray-nozzle and irrigation design.
Does this work for any fluid?+
Yes — density and viscosity are inputs (with common fluids suggested in the field hints), so the same physics applies to water, oils, gases and process fluids. Compute always runs in SI internally, so unit mix-ups can't corrupt the result.
Is the Weber Number Calculator free to use?+
Yes — completely free, no sign-up, no limits. It runs client-side in your browser, so inputs stay private and results are instant even on slow connections.
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