ENGINEERING – HYDRAULIC & OPEN CHANNEL FLOW CALCULATOR
Hydraulic Jump Depth
A precise tool.
What is the Hydraulic Jump Depth & How does it work?
A hydraulic jump occurs when a supercritical flow (high velocity, low depth) abruptly transitions to a subcritical flow (low velocity, higher depth) causing a rapid rise in the water surface. This phenomenon is governed by conservation of momentum and energy, and it is commonly observed in spillways, sluice gates, and openβchannel transitions. The relationship between the upstream depth yβ and the downstream (sequent) depth yβ can be expressed by the classic hydraulicβjump equation derived from the momentum function: The specific energy loss across the jump, ΞE, is obtained by subtracting the specific energies before and after the jump and can be written as ΞE = (yββyβ)Β³/(4 yβ yβ). This loss represents the conversion of kinetic energy into turbulence and heat.
y_{2}=\frac{y_{1}}{2}\left(\sqrt{1+8F_{1}^{2}}-1\right)
yβ = upstream depth (m), Fβ = upstream Froude number = Vβ/\sqrt{g yβ}
Parameters
Result
β
Frequently Asked Questions
What is a hydraulic jump?
A hydraulic jump is a sudden increase in water surface elevation where supercritical flow transitions to subcritical flow.
How do I calculate the downstream depth after a hydraulic jump?
Use the hydraulic jump equation, which relates upstream and downstream depths based on momentum and energy conservation.
When might I encounter a hydraulic jump in real-world applications?
Hydraulic jumps occur in spillways, sluice gates, and other open-channel flow transitions where there is a sudden change from high-velocity to low-velocity flow.
What factors affect the depth of a hydraulic jump?
The depth of a hydraulic jump is influenced by upstream depth, discharge rate, channel geometry, and friction losses.
Can you explain the difference between supercritical and subcritical flow?
Supercritical flow has high velocity and low depth, while subcritical flow has lower velocity and higher depth.
What are some common engineering applications of hydraulic jumps?
Hydraulic jumps are used in spillways to dissipate energy, in sluice gates for water level control, and in open-channel transitions to stabilize flow.
How does the hydraulic jump equation help in designing channels?
The equation helps engineers determine the appropriate channel geometry to achieve desired flow characteristics and prevent erosion.
Results are for informational purposes only and do not constitute professional advice.