Leaf Blower Airflow

Hello Guest,

A while back, there was a leaf blower thread that has a lot of information. I suggest you check it out at:

http://cr4.globalspec.com/thread/16979#comment189034

One of the nice things too is that, if you post a comment in that thread, all of the people that were involved in that thread will get emails alerting them to another post. All of the people that were knowlegeable on that topic can offer assistance fairly quickly as opposed to starting a new thread (I'm not saying you were wrong for doing that - this is just a better/quicker way).

It is easy to join CR4 and, if you've just a little patience, you can become a member rather quickly. I remember being in school and everything seemed dire and immediate, but becoming a member is well worth it.

Best Regards,

Mike

cfm would be the rpm times the displacement of the blower. Displacement being roughly the volume of the impeller chamber minus the volume the impeller it self takes up. Air speed will be determined by the cfm and the nozzle diameter. Note as you reduce the nozzle diameter pressure increase in the blower. If pressure to high may over load motor or cause blow by around the impeller. If the motor can handle the load the blow by can be reduce by reducing clearances between the impeller and chamber walls.

Actually, I use large blowers a lot and we control the volume by closing or opening the outlet. As the outlet in increased the load increases and as the output is closed the load decreases. We use an amp gauge to judge the relative volume of air and as we open the outlet the amp draw will increase.

I, know that this seems wrong but put your hand over the exhaust on your vacuum cleaner and you can hear the motor running faster because of the decreased load!

We use the INLET, and a funny thing about using the inlet, we don't see a change in amps.

I would have thought the opposite would happen to what you describe. Why wouldn't the draw increase as you close, your building pressure behind your control device, and the amps would decrease as you open it. Very interesting.