Reverse Direction of Optional Features for Axial fans AND Rosenberg
The standard direction of flow is Form B, where air passes through the impeller over the motor. Reverse flow, Form A can be provided on request ( for 3 phase motor only). The resulting performances in reverse direction are:
Volume reduced by 30%.
Pressure reduced by 50%.
Power reduced by 25%.
Guide Vanes of Optional Features for Axial fans AND Rosenberg
Up stream or Down stream guide vanes can be incorporated to increase the fan performance.
Up stream (or inlet ) guide vanes create a swirl effect in the the opposite direction to the impeller rotation. It enables the following fan performance increases:
Pressure 25%.
Volume flow 20%
Motor kw 40%.
Down stream (or Outlet) guide vanes act in the opposite direction to the swirl from the impeller and straighten the discharge air, enabling an improvement in pressure capacity:
Pressure 20%.
Volume flow 0%
Motor kw 0%.
The AMCA Certified Ratings Seal does not apply to performance of guide vanes.
Two-Stage
A contra-rotating two stage axial fan consists of two single stage opposite handed impellers rotating in opposite direction
The contra-rotating system develops approximately 2 to 3 times the static pressure of a single stage impeller system of the same diameter and speed. The two stage system uses 5 to 10% less power and is quieter than a single stage system producing the same work at the same diameter. The air flow can be regulated by idling one stage. A flow reduction of 35% and a power reduction of 50% is possible without losses.
If necessary more stages can be added if pressure demands are higher than what a two stage system can meet.
The AMCA Certified Ratings Seal does not apply to performance of the two stage axial fans.
The contact addresses are to be found in the attachment, or else please phone +49 (0)7940 / 0917 186 894 or email toinfo@rosenberg.com.vn