2006-11-29 06:52:42 · 14 answers · asked by pankaj s 1 in Science & Mathematics ➔ Engineering
Look for blade sets which are balanced for stable operation. To prevent warping, blades should be sealed against seasonal moisture. Outdoor fan blades are constructed of a man-made material that won't warp under changes of humidity. Blade pitch ranges from 8 degrees to 15 degrees. The higher the pitch, the more air the fan circulates at slow speeds. The number of blades ranges from 3 to 5, but has little effect on the amount of air the fan moves.
Whatever be the no. of blades , major cause of concerne is balancing of the blades.all blades should in the same plane and at the same angle.
2006-11-29 16:27:12 · answer #1 · answered by Anonymous · 1⤊ 0⤋
I've never seen a 3 blade ceiling fan. The ones in my house are 5 blade and 4 blade.
2006-11-29 07:00:05 · answer #2 · answered by Chris J 6 · 0⤊ 1⤋
Majority of ceiling fans have three blades, the blades push air downwards. More the number of blades the more air they will be able to push, but it will leave less free space through which the air can be pushed, also it will make the fan heavy, reducing its efficiency. Balancing is another issue, single blade fan will be too difficult to balance. Two blade fans are out there.
2016-05-23 02:35:22 · answer #3 · answered by Anonymous · 0⤊ 0⤋
Actually, most ceiling fans have 5 blades.
2006-11-29 06:54:56 · answer #4 · answered by bgdddymtty 3 · 2⤊ 1⤋
it depends upon the aerodynamics design of the blades , the RPM required and the power of the motor ,
high speed fans have less no of blades but produce noise of cutting air ,,,, while low speed designs employ more n. of blades ... it also depends on the cost of the fan to be manufactured ,, more no of blades increase the cost of fan
2006-11-29 20:57:15 · answer #5 · answered by amit m 1 · 0⤊ 0⤋
It just happens to be the model you have.
Some come in 4, 5, & 6 blade models.
Like overdrive in a car, (r.p.m.'s, gear ratios, fuel consumption) some use more blades at lower r.p.m.'s to increase air movement and reduce energy consumption. Some models use blade pitch for more air movement but, this requires more power to "cut" the blades through the air.
It's all a give and take thing, and buyers choice.
2006-11-29 07:02:07 · answer #6 · answered by WHY? 3 · 1⤊ 1⤋
For balance if it had fewer it would wobble so bad it would fall fron the ceiling in time. Plus three or more blades create a better airflow
2006-11-29 09:44:01 · answer #7 · answered by Scott H 1 · 0⤊ 1⤋
I have two ceiling fans and they both have five blades. It's just a design choice.
2006-11-29 06:57:04 · answer #8 · answered by Gene 7 · 2⤊ 1⤋
3 balances naturally.
Like 3 points defien one circle
ts easy to balance 3 blades and thus cost effective.
however, 4,5 and even more are not impossible.
a turbofan in aeroplane has 100s of blades
people have made fans with 1 or 2 also but that requires careful balancing and thus extra cost.
2006-11-29 07:04:43 · answer #9 · answered by adventurous 2 · 0⤊ 1⤋
To reduce wobbling. There are other configurations also such asfour or five blades; they all follow the same principle.
2006-11-29 06:58:33 · answer #10 · answered by Anonymous · 0⤊ 1⤋