#  Fluid Dynamics 

 



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### Laminar/Turbulent Flow

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Depending on conditions, either type of flow can be observed in a glass tube through which water is flowing.

### Reversible Fluid Mixing

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Surprising reversibility at low Reynolds number. Also a mechanical analog of spin echoes in NMR.  
  
\[[In-Depth Description](/presentations/reversible-fluid-mixing)\]

### Poiseuille's Law

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16-tube water tank to show relation between tube cross-section and flow rate.  
  
\[[In-Depth Description](/presentations/poiseuilles-law)\]

### Viscous Fluid

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Viscosity, Stoke's law, Reynold's number, and terminal velocity are demonstrated at 100 Pascal Sec. (100,000 centipoise); cooled glycerine can be used to show the temperature dependence.  
  
\[[In-Depth Description](/presentations/viscous-fluid)\]

### Poiseuille Double Fountain

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A hose with a smaller opening squirts water higher than an open hose, because of viscosity.

### Big Squirt / Little Squirt

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A double fountain puzzler: which fountain squirts higher—the one with the big opening or the one with the small opening?

### Parachutes

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Drag effect of cross-sectional area is demonstrated by two falling disks of paper.

### V squared Drag

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Accurate determination and analysis of g for falling bodies shows v2 dependency of drag force.

### Diffusion of Bromine Gas

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Gas jar containing bromine linked to second containing air; diffusion can be seen as brown coloration of air jar.

### Diffusion of Colored Water

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Food coloring placed at bottom of water filled jar. Diffusion seen as color moves upwards through clear water.

### Vortex Tube

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This clever tube separates hot and cold air out of a jet of room temperature air and serves as a refrigerator.

\[[In-Depth Description](/presentations/vortex-tube)\]

### Vortex Shedding in Air

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A thin wire, moving through the air, is made to vibrate in the audio range at the vortex shedding frequency.

[In-Depth Description](/presentations/vortex-shedding-air)\]

### Vortex Shedding in Water

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Water moving around a cylindrical pendulum makes the cylinder swing at the vortex shedding frequency.  
  
\[[In-Depth Description](/presentations/vortex-shedding)\]

### Turning Off g

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A cup filled with water has a hole in the bottom. What kind of trajectory does the leaking water experience when the cup is dropped from up high?

### Bernoulli's Principle

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Spinning ball in air stream moves perpendicular to flow in a way dependant on spin direction.  
  
\[[In-Depth Description](/presentations/bernoullis-principle)\]

### Bernoulli Wind Tunnel

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Tunnel with different cross sections shows that pressure is dependant on air velocity.  
  
\[[In-Depth Description](/presentations/bernoulli-wind-tunnel)\]

### Bernoulli Beach Ball

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Beach ball held aloft by an angled air stream.  
  
\[[In-Depth Description](/presentations/bernoulli-beach-ball)\]

### Curve Ball

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A styrofoam ball thrown with a Wham-O Trac-Ball racquet deviates from its principal trajectory due to the Magnus effect.

### Contact Us

**Mailing Address**: Lecture Demonstration Services, Science Center, Rm B-08A, 1 Oxford Street, Cambridge, MA 02138  
**Campus Location**: Science Center B-08A | **Tel**: (617) 495-5824 | **Email**: scidemos-at-fas.harvard.edu