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Rippey574
I am having a hard time right now remembering what the formula is and what its called.

Trying to figure out force and or pull.

What this is basically a fan.
I know the total surface area of the blade is 220.5 square inches, the angel of the blades are 45 degrees.
So I come up with 220.5/45=4.9

Is this the correct way to show the force or pull?
If it is what is the units?
Do you just multiply for more blades?
Does it require the blades to be reciprocal?

Does any one know a better way to do this in another fashion?

Thank you for your time.
mathman
QUOTE (Rippey574+Jul 24 2012, 12:48 AM)
I am having a hard time right now remembering what the formula is and what its called.

Trying to figure out force and or pull.

What this is basically a fan.
I know the total surface area of the blade is 220.5 square inches, the angel of the blades are 45 degrees.
So I come up with 220.5/45=4.9

Is this the correct way to show the force or pull?
If it is what is the units?
Do you just multiply for more blades?
Does it require the blades to be reciprocal?

Does any one know a better way to do this in another fashion?

Thank you for your time.

I am not too familiar with this. However I suspect that to get the force you need to multiply the area by the sine (or cosine?) of the angle, not divide by the angle. For 45° it won't matter. This gives an effective area. To get a force you need a factor for rotating speed as well.
Rippey574
Ok, so you would calculate this as:
220.5*(45sin)=Effective Area
mathman
QUOTE (Rippey574+Jul 25 2012, 02:26 AM)
Ok, so you would calculate this as:
220.5*(45sin)=Effective Area

It is 220.5sin(45°), sin(45°) = √(1/2)
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