During a hydraulic jump in a wide channel, the flow depth increases from 1.1 to 3.3 in. Determine the velocities and Froude numbers before and after the jump, and the energy dissipation ratio.
The velocity before the jump.
The velocity after the jump.
The Froude number before the jump.
The Froude number after the jump.
The energy dissipation ratio.
Answer to Problem 85P
The velocity before the jump is
The velocity after the jump is
The Froude number before the jump is
The Froude number after the jump is
The energy dissipation ratio is
Explanation of Solution
Given Information:
The flow depth after the jump is
Write the expression for the flow depth after the hydraulic jump.
Here, the Froude number before jump is
Write the expression for the Froude number before jump.
Here, the velocity before the jump is
Write the expression for the average velocity after the hydraulic jump.
Write the expression for the Froude number after jump.
Here, the velocity after the jump is
Write the expression for the head loss associated with the hydraulic jump.
Here, the average velocity before hydraulic jump is
Write the expression for the specific energy of water before the jump.
Write the expression for the dissipation ratio.
Calculation:
Substitute
Substitute
Substitute
Substitute
Substitute
Substitute
Substitute
Conclusion:
The velocity before the jump is
The velocity after the jump is
The Froude number before the jump is
The Froude number after the jump is
The energy dissipation ratio is
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Chapter 13 Solutions
Fluid Mechanics: Fundamentals and Applications
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