SMALL - espritmodel.com SMALL - Telemetry SMALL - Radio
Reply
Thread Tools
Old Feb 25, 2004, 11:42 PM
Registered User
CSU Monterey Bay
Joined Dec 2003
33 Posts
gws75x4 vs. gws75x6

Hi there, just a curiosity question. Why does the gws75 with 4 fan blades have more thrust than the gws75 with 6 fan blades?
-Rich
RichRacerMX5 is offline Find More Posts by RichRacerMX5
Reply With Quote
Sign up now
to remove ads between posts
Old Feb 26, 2004, 12:08 AM
Scratch fly,Scratch crash
Roswell, N.M.
Joined Nov 2003
384 Posts
Good question! That one was MY next!

It seems like more would be better! (blades that is.)
scratchbildr is offline Find More Posts by scratchbildr
Reply With Quote
Old Feb 26, 2004, 12:10 AM
EDF rules... :)
AirX's Avatar
Joined Nov 1999
13,648 Posts
Less drag on the motor with 4 blades the motor has less drag (2 less blades to move thru the air) produces more thrust from more rpms albeit only a small amount. Actually this large of a fan with that small of a motor equals low efflux velocity. There is only so much power that can be produced by a speed 400 ie total watts absorbed by the rotor.

Cheers,

Eric B.

Edit: A speed 400 in the 64mm fan would produce more thrust and a greater efflux velocity than in the 75mm fan simply by applying a greater power source to a smaller rotor operating at a more efficient rpm.

Edit 2: For those that are just begining to get into fans, there is only one thing that reigns supreme and that is high rpms and high HP to fly like a jet.
AirX is offline Find More Posts by AirX
Last edited by AirX; Feb 26, 2004 at 12:16 AM.
Reply With Quote
Old Feb 26, 2004, 09:31 AM
Registered User
CSU Monterey Bay
Joined Dec 2003
33 Posts
thanks for clarifying! that makes sense. So if I could change the motor out of the gws75 and put in a more powerful motor with the same diameter I should get more thrust right? Now to find a better motor that doesn't cost alot.....
-Rich
RichRacerMX5 is offline Find More Posts by RichRacerMX5
Reply With Quote
Old Feb 26, 2004, 10:25 AM
EDF rules... :)
AirX's Avatar
Joined Nov 1999
13,648 Posts
Yes, to a point. That poin is reached when the plastic used cannot transfer its energy to airflow and the pitch flattens due to the force of the air on the blades.

Cheers,

Eric B.
AirX is offline Find More Posts by AirX
Reply With Quote
Reply


Thread Tools