List of drag coefficient for basic shapes has no angles

B92X
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When I type "drag coefficient" in Google, and view some of the images, the standard list of geometrical shapes come into view, such as this one:

https://upload.wikimedia.org/wikipedia/commons/thumb/3/37/14ilf1l.svg/220px-14ilf1l.svg.png

If we take the cone for example, there is a drag coefficient of 0.50. But I can't see the degrees, or the angle of the sides. Is not that very relevant?

Is there a "standard cone" with certain ratios?
 
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B92X said:
When I type "drag coefficient" in Google, and view some of the images, the standard list of geometrical shapes come into view, such as this one:

https://upload.wikimedia.org/wikipedia/commons/thumb/3/37/14ilf1l.svg/220px-14ilf1l.svg.png

If we take the cone for example, there is a drag coefficient of 0.50. But I can't see the degrees, or the angle of the sides. Is not that very relevant?

Is there a "standard cone" with certain ratios?
What is your guess?
 
Chestermiller said:
What is your guess?

I looked at the Collins dictionary, and it states that "a cone is a shape with a circular base and https://www.collinsdictionary.com/dictionary/english/smooth curved sides https://www.collinsdictionary.com/dictionary/english/ending in a point at the top."

I can't seem to find a definitive ratio, this would be far more obvious for a cube as it's edges are clearly at 90 degrees.
 
The value is just an approximation. Certainly, the drag coefficient will also be a function of the Reynolds number and of the cone angle. But, to get a rough estimate, using 0.5 is probably going to give a decent approximation over a typical range of Reynolds numbers and cone angles. My advice is to keep looking for additional information and references if you need a more accurate estimate.
 
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