Reference area, in drag coefficient formula

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In the drag coefficient formula, the reference area for boats and ships is not solely the submerged surface area; it varies based on the type of drag being measured. For automobiles, the reference area is typically the frontal area, while for airfoils, it is the chord length. The specific reference area can differ significantly depending on the object's shape and the medium it moves through. Understanding these distinctions is crucial for accurate calculations of drag. The topic emphasizes the importance of context in determining the appropriate reference area for different applications.
Demson
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hi

small question

in the drag coefficient formula

for boats and ships, is the reference area, the surface area of the submerged part of the ship/boat?

demson
 
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Welcome to PF!

Hi Demson! Welcome to PF! :smile:

It depends … see http://en.wikipedia.org/wiki/Drag_coefficient" for details :wink: …
The reference area depends on what type of drag coefficient is being measured. For automobiles and many other objects, the reference area is the frontal area of the vehicle (i.e., the cross-sectional area when viewed from ahead). For example, for a sphere A = π r2 (hence not the surface area = 4 π r2).

For airfoils, the reference area is the chord …

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Thread 'Mousetrap Car Energy efficiency'

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