An anemometer is an instrument designed to measure the speed of the wind. There is a various range of anemometers created for specific types of environments, measurements, and situations. One of the basic models is the cup anemometer, and newer, more accurate devices are based on laser or ultrasonic measuring technology.
A Robinson anemometer, a utilized name for the cup anemometer, uses cup-like pieces to catch the wind, making the device rotate. The number of the spins in a limited time interval allows you to calculate how quickly the wind is moving. This article represents an example of how an anemometer can be built.
Materials needed to build an anemometer
A cup anemometer is an uncomplicated device, which means that you can start your own science project and create one yourself. You do not need any complicated things like a lab bench or like a lab cabinet, nor other types of lab devices.
For this experiment, you need five paper cups, a hole punch, scissors, duct tape, three wooden dowels, an empty water bottle and a stopwatch.
Steps in building an anemometer
First, make a hole in each of the paper cups, using the hole punch.
Secondly, again using the hole punch, make four evenly spaced holes around the rim of the fifth cup. This will represent the center of the device.
Afterward, through the holes in the center cup, slide two of the wooden dowels. If everything is done correctly so far, they should cross in an “x”.
The next step is to insert the ends of the dowels into each hole of the other four cups, and then tape them into place. Do make sure all the cups are oriented in the same direction.
Next, make a hole in the bottom of the center cup with the last wooden dowel.
Then, you should push the dowel up, until it meets the “x”. When you are done, tape everything together. This will be the rotation axis.
Last, out the center dowel into an empty water bottle, and you are almost done! You have made your very own homemade anemometer.
Calibrating your anemometer
After you have finished your construction, it is time to calibrate data. Here is an elementary example of how you could do that: on a day with no wind, have someone drive you at 10 miles per hour.
When the desired speed has been reached, hold the device out the window and simply count the number of spins per 30 seconds.
Regardless of how many times the anemometer rotates over 30 seconds, the rotations will correspond to a wind blowing at 10 miles per hour.
On multiple windy days, you can take your device outside, and measure its speed and then compare the data you got. If you take it to different locations, you might notice you obtain various results. Try on an open field, on a beach by the sea or ocean, and in a narrow passageway.
Calibrating your anemometer is the next important step after you have finished putting together your device. This process offers you a basis for comparing the data you have collected. For instance, if your device rotates 10 times in 30 seconds, on a 10 miles per hour test run, then you can tell that 10 rotations in 30 seconds means the wind speed is 10 miles per hour. When you want to calibrate your data, you can try various speeds and make a chart of the results you have obtained.
Why build an anemometer?
As you might have noticed by reading this article, cup anemometers are uncomplicated devices that are usually used by meteorologists in order to determine the speed of the wind.
The guide above shows that you can make such a device with no difficulty, using everyday household items.
As easy as it seems to put together an anemometer, you might wonder why you should actually build one. Well, for instance, it can help you understand this subject better if you are studying in this field. If you are done with school and have no connection whatsoever, it could be a fun activity if you start it with your kids. Either way, it can prove to be a lot of fun.