Engineering STEAM Kit - Anemometer

Build an Anemometer

An anemometer is a device used to measure wind speed and wind pressure. There are different types of anemometers, but the most common type is the cup anemometer. A cup anemometer has three or four cups mounted on a vertical pole. The cups capture the wind which rotates the pole. The wind speed is determined by counting the number of rotations over a specific time period. An anemometer can be manual or digital.

There are many different uses of an anemometer, such as:

Meteorology - Used for weather forecasting, climate research and other meteorological applications.
Wind Farms and Turbines - Used to determine the best location for wind power generators and turbines. Also, large wind turbines even have built-in anemometers to measure wind speed and stop the turbines from rotating if the wind blows too fast.

Coal Mines - Used to determine how much airflow is entering or exiting mines. This helps ensure miners have good ventilation and enough air to breathe while underground.
Construction - Used to assess the wind around a building to determine its structural design and wind resistance.

Did you know?

The word ‘anemometer’ comes from the Greek word for wind, which means anemos?
NASA is considering a mission to Venus that would use an anemometer to measure wind speed on the planet to gain insight into Venus' surface and atmosphere.

Design Challenge:

Become a metrologist and build an anemometer to measure the wind speed at various locations around your home and school.

Measure the wind speed by counting the number of times the anemometer spins around in a minute (rotational rate).

Find 2 - 3 locations around your home or school. Using your anemometer, take three measurements at each location. Calculate the average rotational rate of your anemometer at each location. Which locations had the highest and lowest rotational rates?

Materials:

5 - 3 oz paper cups
2 - Straws
1 - Pushpin
1 - Sharpened pencil with eraser
1 - Pen or Marker

Build Instructions:

Use the tip of a sharpened pencil (or a hole punch) to punch four holes in a paper cup just below the rim, forming a "+" shape (two pairs of holes opposite each other).
Press two straws through the holes (See Figure 1)
Use a sharpened pencil to poke a hole in the center of the bottom of the cup (See Figure 2)
Use the pencil to punch two adjacent holes in each of the other four cups. The holes should be about 2–3 cm apart, and about halfway along the cup's height (See Figure 3)
Push the end of a straw through the two holes in each one of the cups, as shown in Figure 3. Make sure the cups are all facing in the same direction (all clockwise or all counterclockwise). There should be enough friction to hold the cups in place so they do not twist on the straws. If the cups twist easily, use a bit of tape to secure them.
Push the pencil, eraser end first, through the hole in the bottom of the central cup.
Press a pushpin lightly through both of the straws and into the eraser, as shown in Figure 4. Do not press the pushpin into the eraser all the way, or there will be too much friction and your anemometer will not spin.
Use a pen or marker to draw an easily recognizable symbol (for example, a dark circle or band) on the side of one of the cups, so you can easily tell it apart from the other cups. This will make it easier to count revolutions when the anemometer is spinning.