Floating Water

Final Report


Table Of Content

INTRO

PROJECT DISCRIPTION

FUTURE WORK

CONCLUSION

BIBLIOGRAPHY

ACKNOWLEDGEMENTS

Intro

Our project determines the time and distance virga takes place. Virga like we explained in the summary, is the phenomenon of falling rain that we see but never reaches the ground. By analyzing the suspended drops in our wind tunnel we will see the differences of the time the drops take to disappear, by the shape and the wind speed. Our wind speed will be a constant of 849.5 rpm's. We will have to use more or less screens to change the wind speed. Barry brought the design of the wind tunnel to us in a book he was reading. We sort of did the blue print out of nowhere because all we had was a picture. We constructed the wind tunnel at school and painted it at school.
Our computer program will predict the time the drop will disappear and at what speed did it disappear. It will also, if we can, predict its volume and it's shape while in air and at what times it will change. We will use different size of drops and see the differences and the shapes they make. The results of our test will be used to draw conclusions about virga.
After studying virga and its effects, we have better understanding of why virga happens and how.

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PROJECT DISCRIPTION


Our group is going to study motion using photography and a drop of liquid. We will incorporate a drop of water suspended in a vertical wind tunnel. We will take pictures of the drop at different wind speeds and drop sizes. The pictures will then be analyzed by us and studied. We will then use the pictures to see the differences of the drops by shape and speed. We will then use that data to make a c++ program to calculate the drops shape and its change in form at the different speeds. Our reason for this project is to determine the conditions on which virga can occur.

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FUTURE WORK

The United States Air Force supplied us with all the materials for the wind tunnel. Our group will have to get permission from the Air Force in order to obtain the wind tunnel.
After clearance is given by the Air Force, the wind tunnel will either be donated to the science department of Bernalillo High School, or it will be used for future A.i.S. Challenges. We would like students at our high school to get an opportunity to benefit from such a diverse way of learning.
If the wind tunnel is used for future A.i.S. Challenges, our group will expand further on the topic of motion with water droplets, through the Internet and e-mail exchanges with students from around the state who are also interested in the same topic.

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CONCLUSION

The results from our experiment are inconclusive so far. Our original design did not work so we are still trying different modifications. The four to five screens that are suppose to control the air speed and the turbulence have proved to be too much resistance for the amount of air speed our fan puts out. We pulled two of the screens out, redesigned the third, and by taking out the bottom half of our wind tunnel we have increased the air speed to hold the drop in mid-air. From our trial and error techniques we can see the basic shape of the drop as it falls. We have seen the effect of virga on the drop as the wind surrounds the forming water droplet. The effect doesn't take more than a few seconds to take place and as it does, controlling the drop becomes more difficult.
The drop forms a dome shape as it falls from the dropper which makes it hard to control. If the drop forms too large the shape is more like a flat bubbly plane. At that point, the strain on the drop is too much for the surface tension to hold it together. As the larger drops float around much like a puck in air-hockey it slides around quite a bit until it breaks up into smaller drops. The smaller the drops are easier to control, but they don't last long due to the virga effect. We are continuing the experiments until we produce more accurate results.

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BIBLIOGRAPHY

http://www.mit.edu
http://www.rit.edu
http://www.go2net.com
http://www.grainger.com
Dr. James E. McDonald

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ACKNOWLEDGEMENTS



Our group would like to thank the following individuals:

Mr. Barry Berendberg
Ms. Ronda Cole
Ms. Candace Martinez
Ms. Jennifer Coughlin
Mr. William Brooke

Thank you for all your help and dedication, Which was essential in making this project a success.

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LINKS



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Progress & Plans

Materials & Supplies

Timeline

Formulas

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