 |
|
|
Venturi Effect
by Jeanette Cain
High-rise apartment buildings on the beach cause erosion. In 1989, a New Jersey town banned the building of more high-rise apartments near the beach. Tall buildings deflect winds, causing air to pass through a small area and increasing the air's velocity. The wind must move faster since it is traveling further.
When high-rise apartments are built next to each other there is only a small space between them. As the wind hits the buildings directly, it is sucked through that space by the air that is moving through it. This is called the Venturi Effect.
This project involves a simulation of showing the effect a high-rise building might have on beach erosion. Consider that moving air will pick up sand particles in front of the building and deposit these particles to the sides behind the structure.
YOU WILL NEED:
1. Wooden frame box: 2 feet by 4 or 5 feet; 1 to 2 inches deep.
2. Sand (Beach or Playground).
3. Three speed fan
4. A brick
FIRST: Make a sandbox out of wood with the above measurements. Its depth can be shallow (1 to 2 inches). Fill your box with sand; the sand needs to be level. Set the fan at one end of the box and stand your brick upright about one foot from the fan.
NEXT: Allow the fan to blow for a lengthy time while observing any sand erosion and the places where the sand is being deposited. Draw a diagram showing the results of your experiment, and make a conclusion.
EXTRA: You can carry this experiment further by calculating different wind velocities with a 3-speed fan. You can also use differing points around high-rise buildings using a hand-held anemometer.
Source:
1. Bonnet, Robert L. and Keen, G. Daniel. Earth Science: 49 Science Fair Projects. Tab Books: PA. 1990 pps12-13.
|
|
|
|
|
