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APPH 4200 Physics of Fluids
Waves (Ch. 7)October 28, 2010
1.!! Waves2.! Linear gravity waves at a free surface
1
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Wave Energetics
20
Summary• Waves: phase fronts, phase velocity, wave
packets, group velocity.
• Linear waves (vs. nonlinear)
• Surface gravity wave:
- Velocity potential, Laplace’s Equation
- Assume top surface varies as η0cos(kx - ωt)
- Bernoulli’s Principle at surface
- No vertical flow at bottom
- Partition between Kinetic ⇔ Potential Energy21
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