View Full Version : Building a Cyclone - question!

Niels J. Larsen
10-21-2005, 3:19 AM
I've decided to try to build a Cyclone based on Bill Pentz' design and since first thing's first - I've been trying to track down a usable motor for the unit.

Bill Pentz bases his Fan Table and all other calculations on a motor that runs at 3450rpms (regardless of HP).

The motors I can get my hands on here in Denmark run a maximum of 2800rpms. If I need more rpms I'll have to add some type of gearbox or use drivebelt to connect the Cyclone to the motor.

How much airflow will I loose by using 2800rpms instead of the 3450rpms and will I need to go for a bigger motor than I'm currently planning to use (which is a 4kW/5.5HP motor with 14" wheel) ?

I should point out that this Cyclone will be driving a small 1-car garage with either 6" or 7" ducting with a max run of about 15 feet.

I guess there must be a formula to calculate this, so any help appreciated!