Since 30 years, over the world, antifrost windmachine are generally two bladed are really noisy
The main objective of SOA is to reduce this noise in order to protect neighbours
Compared spectral noise analysis between a 2 bladed windmachine and SOA rotor
P1 2 bladed at 120m
P1 S.O.A. fan at 120m
This fan can be fit up on any kind of existing 2 bladed machine
A major technological evolution..
The origin fan nois provid from several factors :
Interaction between vortex and blades
High speed impulse noise
Working on several of these factors and with a straight combination of those, S.O.A. has reduce drastically the noise.