Mechanical & Civil Engineering
Water Hammer (Joukowsky) Surge Pressure Calculator
Estimate the pressure surge caused by sudden valve closure in a pipeline using the Joukowsky equation.
Your inputs
Change any value to update the result instantly.
Surge pressure rise
2,400 kPa
Surge head rise
244.65 m
Total peak head
294.65 m
Wave celerity used
1,200 m/s
What this calculator does
Water Hammer (Joukowsky) Surge Pressure Calculator: Applies the standard civil and geotechnical relationship for this problem so the flow, pressure, settlement or capacity can be worked out from measured site inputs.
What your result means
The headline figure is the hydraulic or geotechnical quantity implied by your site inputs. Compare it against the design criteria in the applicable code before acting on it.
Formula and working
ΔP = ρ × a × ΔV
- 1
Collect the inputs
Fluid density = 1,000 kg/m³; Pressure wave celerity = 1,200 m/s; Flow velocity change = 2 m/s; Static pressure head = 50 m
- 2
Apply the formula
ΔP = ρ × a × ΔV
- 3
Result
Surge pressure rise = 2,400 kPa
Frequently asked questions
Symbols and assumptions
- density
- Fluid density (kg/m³)
- waveSpeed
- Pressure wave celerity (m/s)
- velocityChange
- Flow velocity change (m/s)
- staticHead
- Static pressure head (m)
- • Steady-state, single-phase conditions are assumed unless the page says otherwise.
- • Site inputs (soil properties, flow, roughness) come from the user's own survey or testing.
Sources and review
Reviewed 2026-09-22 · Next review 2027-09-22
- • This is an educational estimate for learning and checking, not a design deliverable.
- • Real design must follow the governing code or standard for your jurisdiction and be reviewed and signed off by a qualified engineer.
- • Safety factors, load combinations and material certification are the responsibility of the designer, not of this page.
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
Report a mistake or request an improvement
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