number of rotor blades

I got the formula in the rotorcraft forum. If i remember correctly
it was written by Chuck Beaty
The units is in pounds and feet, thus imperial.
Yes we use the metric system but I was still brought up with the
imperial system so I still think that way.

Regards

Hennie


wrote in message ...
Just guessing, but your formula uses Velocity and his uses RPM. The
2900 is probably due to the conversion of RPM to velocity in Miles Per
Hour.

V = (2*R*RPM)/28 (where units are V=Miles Per Hour, R=Feet)

Also, your formula is apparently using Kg's and M's instead of Feet
and pounds. Then again, I may be totally wrong as CAC is from South
Africa and they use the metric system too. (I know this because I did
a search for apartments in South Africa and all the square 'footage's
were in square meters.)

It would help if somebody would say for sure what the units are.

Dennis.

"Cam" wrote:

Hi, I was wondering if there was a simplified formula for working out
centrifugal force with a constant mass rotor.
Unfortunately I can't make sence of it, what is the constant 2900 derived
from?
When using, F= MV^2/r
F= force
M= mass
V= velocity
r= radius
By summing each calculation -- say at r=1m, 'X'm/s,M=1Kg
r=2m
'X'm/s,M=2Kg
and so on .(the smaller the increments the better)
The end result is not even close to the formentioned formula.
Where have I gone wrong?

Cheers Cam
(excuse the metric system)

"Hennie" wrote in message
om...
The centrifugal force generated by a rotor blade
is (W*r*rpm^2)/2900 W is the blade weight. r is the distance from
the hub center to the CG of the blade



Dennis Hawkins
n4mwd AT amsat DOT org (humans know what to do)

"A RECESSION is when you know somebody who is out of work.
A DEPRESSION is when YOU are out of work.
A RECOVERY is when all the H-1B's are out of work."
To find out what an H-1B is and how they are putting
Americans out of work, visit the following web site
and click on the "Exporting America" CNN news video:
http://zazona.com/ShameH1B/MediaClips.htm