Hydraulic jump calculator

Inputs in the worked example

The live calculator starts with these values; change any of them and every result, check and diagram updates instantly.

Worked example — results

• ✓ Supercritical inflow (Fr1 > 1)

Method, formulas and assumptions

• V1 = 3/0.35 = 8.5714 m/s
• Fr1 = 8.5714/SQRT(9.81*0.35) = 4.6258
• y2 = y1/2 (√(1 + 8Fr²) − 1) = 0.35/2*(SQRT(1+8*4.6258^2)-1) = 2.1213 m
• Energy loss (y2 − y1)³/(4 y1 y2) = (2.1213-0.35)^3/(4*0.35*2.1213) = 1.8714 m
• Jump length ≈ 6 y2 = 6*2.1213 = 12.728 m

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