Hi all,

I work in dubai as HVAC designer. Can anyone please help me in sizing an exhaust fan for a generator with an exhuast of 118 m3/min. However the exhaust gas will have its own velocity to carry itself through the duct, but to avoid any back drop I have decided to provide a fan which wil boost up the flow.

Exhaust outlet of generator is of 200mm dia, & it shall be connected to a duct of 300mm dia as we proposed.

But my query is, how much shall be the capacity of exhaust fan?
I believe it shall not be equal to the exhaust flow (which is too high) but much lesser than it as the fan is just to assist in the gas flow out of the room.

I have roughly selected a fan of 470m3/hr.
Please help me know the flow & esp the fan shall have?