theroretical calculation of acfm of a radial blade fan

[PNA]

with knowing blade thickness, inner and outer diameter, it has a back support, depth of blade is known

any ideas

thanks

paul

 

[imok2]

This may be of some help for you

http://www.hudsonproducts.com/products/tuflite/flowfans.pdf

 

[PNA]

thanks, but its more to do with axial fans which are very predictable from a design standpoint, where the centrifugal fan designs are not as much...

i know there are efficiencies lost with various designs, sizes, speeds, etc, but there must be a way to calculate ideal air flow based on a prototype design without having to build it

 

[ChrisConley]

Computational Fluid Dynamics are used for predicting flow without building. Quite a few of the major fan manufacturer's are using CFD now.

 

[PNA]

hmmmm....if i had a few grand or better, i would just run out and buy that instead...thanks anyways

 

[KiwiMace]

If you want a cheap way of estimating the performance of a given fan design, go download the performance curves of a geometrically similar model from a quality manufacturer.

What you are asking for is specialist knowledge beyond a normal engineering curriculum or experience typically acquired in this discipline.

To Chris' point, CFD is a lot cheaper than prototype trial and error. If you are serious about building fans, then it is not a big outlay. If this is for one fan, then buy one. If you simply must build your own, then copy someone elses and good luck.