Boundary Layer Thickness Calculator (Flat Plate)
Laminar/turbulent boundary-layer growth along a flat plate at distance x.
At 10 m/s in air the layer turns turbulent ~0.75 m from the leading edge — and a turbulent layer grows ~5× faster than laminar.
Formula
Boundary Layer Thickness Calculator (Flat Plate) is a free boundary layer thickness 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 Boundary Layer Thickness Calculator (Flat Plate)
Laminar/turbulent boundary-layer growth along a flat plate at distance x. The calculation implements Laminar: δ = 5x/√Re_x; Turbulent: δ = 0.37x/Re_x^0.2 (Schlichting, Boundary-Layer Theory). At 10 m/s in air the layer turns turbulent ~0.75 m from the leading edge — and a turbulent layer grows ~5× faster than laminar.
How to use Boundary Layer Thickness Calculator (Flat Plate)
- 1Enter Free-stream velocity in m/s.
- 2Enter Distance from leading edge in m.
- 3Enter Kinematic viscosity in ×10⁻⁶ m²/s (Air 20 °C = 15.1; water = 1.0).
- 4Read Re_x, BL thickness δ instantly — no submit button needed.
- 5Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Boundary Layer Thickness Calculator (Flat Plate)?
- ✓Implements the standard formula — Laminar: δ = 5x/√Re_x; Turbulent: δ = 0.37x/Re_x^0.2
- ✓Reference cited on-page: Schlichting, Boundary-Layer Theory
- ✓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 Boundary Layer Thickness Calculator (Flat Plate) use?+
It computes Laminar: δ = 5x/√Re_x; Turbulent: δ = 0.37x/Re_x^0.2, per Schlichting, Boundary-Layer Theory. 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?+
At 10 m/s in air the layer turns turbulent ~0.75 m from the leading edge — and a turbulent layer grows ~5× faster than laminar.
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 Boundary Layer Thickness Calculator (Flat Plate) 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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