ceiling fan blades
 

We see ceiling fans with 3, 4 and 5 blades. Does blade number matter
for performance, quiet, vibration, etc?

Thanks

Lynn Willis
Indianapolis

ceiling fan blades
 

On Nov 13, 12:43 am, " wrote:
We see ceiling fans with 3, 4 and 5 blades. Does blade number matter
for performance, quiet, vibration, etc?

Thanks

Lynn Willis
Indianapolis


Fans with three or four blades move more air than five or six blade
fans. They are harder to balance than the five or six blade fans
though.

ceiling fan blades
 

Fans with three or four blades move more air than five or six blade
fans. They are harder to balance than the five or six blade fans
though.


I completely disagree. I would never buy a four blade fan. Five
blade fans move MUCH more air. I've replaced all the 4 blade fans in
my house with 5 blade fans and the results are much better.

Go for the biggest diameter you can, too. Makes a difference.

ceiling fan blades
 

"spammer" wrote in message
ups.com...
On Nov 13, 12:43 am, " wrote:
We see ceiling fans with 3, 4 and 5 blades. Does blade number matter
for performance, quiet, vibration, etc?

Thanks

Lynn Willis
Indianapolis


Fans with three or four blades move more air than five or six blade
fans. They are harder to balance than the five or six blade fans
though.


The number of blades indicates nothing. The size, pitch, airfoil design,
and rotational speed determines how much air it will move. Take a look at
airplane propellers.

ceiling fan blades
 

You proved the other poster's point. Many light civil aircraft have
two bladed props. Light and low powered WWI had two. High performance
fighters and heavy bombers from WWII have four blades. More blades
move more air.


On Nov 13, 5:51 am, "Edwin Pawlowski" wrote:
"spammer" wrote in message

ups.com...

On Nov 13, 12:43 am, " wrote:
We see ceiling fans with 3, 4 and 5 blades. Does blade number matter
for performance, quiet, vibration, etc?

Thanks

Lynn Willis
Indianapolis

Fans with three or four blades move more air than five or six blade
fans. They are harder to balance than the five or six blade fans
though.

The number of blades indicates nothing. The size, pitch, airfoil design,
and rotational speed determines how much air it will move. Take a look at
airplane propellers.

ceiling fan blades
 

ceiling fan blades
 

On Nov 13, 12:43 am, " wrote:
We see ceiling fans with 3, 4 and 5 blades. Does blade number matter
for performance, quiet, vibration, etc?

Thanks

Lynn Willis
Indianapolis

Here's my response from an earlier thread regarding ceiling fan
blades:

Disclaimer: I don't work for a fan company so none of this is a
testmonial or sales pitch. It's just info...

Here's some quick info on ceilings fans, both of which include some
verbage on blades angles.


http://www.garbes.com/inform/fanfaq.html
http://www.ehow.com/how_110234_choose-ceiling-fan.html


Stolen without permission from http://www.hansenwholesale.com/ceili...anca/about.asp


*** Begin Included Text ***


"Don't let your ceiling fan leave you hot under the collar... Just
because a ceiling fan moves air doesn't mean it moves enough air to
keep you comfortable. The blade pitch (or angle) determines how much
air is moved when the fan is on. Some fans have blades with a very
shallow pitch because their motors are not powerful enough to handle
the extra demand made by steeper blade pitches. Casablanca fans use a
motor which is engineered to be more than powerful enough to operate
fan blades with a full 14 degree pitch. So you always get the right
amount of air to keep cool and comfortable."


*** End Included text ***


Interesting fact: The first 3 fans listed under the model section at
that site are 3, 4 and 5 blade fans. The 3 blade has an air flow
rating
of 4 out 5, while the 4 & 5 bladers are rated 5 out of 5. Casablanca
claims 5 is the best, but I don't know if that's their standard or an
industry standard.


Bottom line: If a fan isn't bragging about it's blade angle and motor
quality as selling points, that may mean it's not as steep or strong
as one would like. My guess is that no one is putting a motor that
can
handle a 14 degree pitch on a fan with an 8 degree pitch, if you know
what I mean.

ceiling fan blades
 

George wrote:

You proved the other poster's point. Many light civil aircraft have
two bladed props. Light and low powered WWI had two. High
performance fighters and heavy bombers from WWII have four blades. More
blades move more air.


Actually he didn't. The number of blades have nothing to do with
efficiency. The most efficient propeller is actually one blade. Multi
blade designs are used for other reasons.

Like modern submarines with, what, TWENTY blades on the propeller?

ceiling fan blades
 

HeyBub wrote:
George wrote:
You proved the other poster's point. Many light civil aircraft have
two bladed props. Light and low powered WWI had two. High
performance fighters and heavy bombers from WWII have four blades. More
blades move more air.

Actually he didn't. The number of blades have nothing to do with
efficiency. The most efficient propeller is actually one blade. Multi
blade designs are used for other reasons.

Like modern submarines with, what, TWENTY blades on the propeller?



Now you're touching on why you want more blades - they run quieter.

--Steve

ceiling fan blades
 

wrote in message
ps.com...
You proved the other poster's point. Many light civil aircraft have
two bladed props. Light and low powered WWI had two. High performance
fighters and heavy bombers from WWII have four blades. More blades
move more air.

Still goes back to total design, not just numbers. Look at the blades on
the huge windmills used to generate electric. Usually three long narrow
blades.

As for aircraft, one reason to use the three or four blades over just two is
ground clearance. When the tail comes up, you don't want the blade to hit.

ceiling fan blades
 

Steve wrote:
HeyBub wrote:
George wrote:
You proved the other poster's point. Many light civil aircraft have
two bladed props. Light and low powered WWI had two. High
performance fighters and heavy bombers from WWII have four blades.
More blades move more air.

Actually he didn't. The number of blades have nothing to do with
efficiency. The most efficient propeller is actually one blade. Multi
blade designs are used for other reasons.

Like modern submarines with, what, TWENTY blades on the propeller?


Now you're touching on why you want more blades - they run quieter.

--Steve

Exactly, a lot more to do with trying to achieve stealthier operation
than any other reason.