|
Incomparably Quiet
- Tipless blade = Noiseless operation |
|
|
|
|
Getting rid of the cause of noise, "tip-vortex" |
Getting rid of the cause of noise, "tip-vortex"
When considering noise pollution, quiet operation is an element of a small wind turbine that can never be overlooked. Among several different sources of noise emitted by a wind turbine, a sound created at the tip of each rotating blade (tip-vortex) is far bigger than all the other sound, including mechanical and vibrating sound. Once a tip-vortex forms, noise level elevates swiftly by as much as 30dB.
Blades on this product are in a loop-shape and therefore have no pointed tip to create a vortex. This means that, fundamentally, the very cause of troublesome noise has been removed. |
|
|
Tip-vortex forms at a tip speed of 50 meters per second (m/s), regardless of rotor diameter. With its fluid dynamic characteristics, these Wind Turbines create high torque at relatively low rotation speeds. It is designed to not exceed a tip speed of 40m/s even in a wind speed of 12m/s with no load on generator, while some propeller product operates at a tip speed as high as 150m/s (540km/h).
Together with the tip-vortex-free mechanism, the low speed rotor achieves unparalleled quietness.
|
|
Noiseless even with no load on generator |
|
A test conducted at Mie University in April 2007 shows that a difference in noise level between the wind tunnel ventilator alone and the ventilator + the Wind Turbine (no-load condition) is virtually the same in wind speeds of 8m/s and 12m/s. Further test was conducted in a wind speed of 14m/s with no load on generator, and unpleasant noise deriving from the turbine was not detected by human ears. |
|
|
|
 |
