Thread: 50hz versus 60 hz cyclone

You will get slightly better preformance from a forward curved impellor, but with alot more noise.
Backward curved impellers are quieter than forward curves or flat ones
For those that care - a typical material handling impeller generates at best about 45% efficiency versus roughly 80% for an airfoil but airfoill impellers are designed to work with a constant suply of air and very little resistance. with too little air or too much resistance, they can stall producing vibration which can be destuctive.
It's always going to be a trade off, and while some people are determined to redesign the wheel, i'm happy with thousands of hours of design that's already gone into it.
Perhaps you'd like to comission an engineer to design a more efficient fan, have a one off fabricated and tested, and come back and let us know how much it cost and whether or not it was worth the extra dollars for the extra 3% airflow, But Seriously, alot of design has already gone into these things.