http://www.alton-moore.net/wind_calculations.html
http://www.warlock.com.au/bladecalc-abstract.htm
Both of these are very good blade calculators, my favorite is warlock's because it converts meters to inches and feet for you.
Now,as an example put in warlock's calc. click on the metric button
3 blades
6 tsr
.35 eff
1 m radius blade size
10.1 kph
now click imperial button your chord should read 2.404" long ,at the tip. at an angle of 0.3 degrees, angle beta.
maybe i have been spoiled because i can change the angle of attack of the whole blade even after its done. Just by pivoting the blades a tad this way or that.a nice feature to be sure
What happens if you want to change the length ( radius) of the blade and get the calc to output in inches? easy , just go back and click the metric button , put in .875 m radius , click solve , then click imperial this gives you a blade radius of 2.9 feet , if you then click solve again, notice the length is back to 3 feet it must be a conversion problem in th program , dont know..
some things i've noticed and have some questions on:
for a given TSR , both calculators assume a AOA , let me explain
TSR - Altons - Warlock
9 - 4.2 - 4.2
8 - 4.7 - 4.8
7 - 5.4 - 5.4
6 - 6.3 - 6.3
5 - 7.6 - 7.6
4 - 9.4 - 9.5
at these angles for each calculator the tip ends up at 0 degrees ,when you change the airfoil from NACA 2412 to a user defined airfoil
how is it that the NACA 2412 is defined by its Cl of .85 at an alpha of 6 degrees?
another observation i've made is that for any given set of parameters , lowering the lift coefficient , increases the chord length to make up for the lower Cl .
.