General notes on blowing outlets
In factory heating with warm air on the overhead plenum system, the outlets are typically from 150 mm to 275 mm diameter at 3 m to 3.8 m above floor level with an average velocity of 5 m/s to 6 m/s (see Figure 3.30). The sophistication of outlet grilles is rarely merited other than for aesthetic reasons.
Figure 3.30 Typical outlets for factory plenum heating system
For general ventilation of factories, similar outlets may be used. Common examples are in the ventilation of very hot workrooms such as those for pressing and finishing of garments, laundry ironing rooms, etc. Tapered outlets have been used in some installations (see Figure 3.31 ). An outlet velocity of 3.75 m/s to 5 m/s has been found satisfactory.
Figure 3.29 Reduction of width of issuing airstream with increased angle of deflection
Posted in Fans Ventilation A Practical Guide