What is the drag coefficient of a square piece of paper in aerodynamics?

AI Thread Summary
The drag coefficient of a square piece of flat photocopying paper is estimated to be around 1.7-1.9 when traveling against its face. The discussion also highlights the potential for paper deformation during experiments, which could affect the drag coefficient. The user is exploring low-mass materials with high drag coefficients for their aerodynamic experiment, finding paper to be the most practical option. They initially considered aluminum foil but determined it is lighter than paper, making it less suitable. Overall, the user seeks reliable data on drag coefficients for thin-sheet materials while conducting freefall time measurements under varying pressures.
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Hi,

I am designing an experiment for an individual project and it happens to involve aerodynamic. I wonder if someone can give me some idea of the drag coefficient of a square piece of flat paper (the normal 80grams photocopying paper) traveling through air against its face? (i.e. not traveling along the edge)

I'm guessing roughly 1.7-1.9 according to the data for "flat surface (square)" from a website. Is this supposed to be right? Is there any other shape I can make out of this kind of paper which will give higher drag coefficient?

Thanks!

*EDIT: Oh and also, does anyone know the approximate mass per area of those thin aluminium foil used for food wrapping? Because if it doesn't weigh too much more than the photocopying paper then it'd probably suit the experiment better (the area will be somewhere around 25sq.cm.)

*EDIT2: Never mind about the aluminium foil thing, I managed to work it out by using density data. Turns out that it weighs even less than the paper. Information about thin-sheet square drag coefficient would still be appreciated though ^^
 
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That is a good starting point, but do understand that the paper is going to deform and thus change geometry and drag coef.

Did you look here?
http://aerodyn.org/Drag/tables.html#bluff
 
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Hmm.. I didn't expect the paper to deform at around 100psi actually.. I'm just planning on measuring freefall time under different pressures.. I guess I'll have to see.. (I wouldn't imagine a large amount of deformation over a 3m freefall actually, I might be wrong though)

I'm just looking for something with really really low mass and high drag coefficient actually. Been playing around with the graphs and found that paper is the best candidate so far for the experiment as it's the most "practical" to measure the data.

And yes, that was the page I got my data from.
 
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