Duct Sizing

[westleaf]

I need to relocate the suction air filters for 2 7500 acfm blowers due to high particulate loading. The thought would be to use some existing 28" diam. duct which is available and move the filtering point about 60' away (we would also have 4 90 degree elbows) from the existing location of the blowers. Any tips on where to find estimated pressure losses for this flow in 28" diam. duct? The flow would be 7500 acfm in each duct.

 

[VEEKRISH]

For 7,500 cfm and 28" dia duct, the friction factor works out to 0.14" per 100 ft of duct. calculate equivalent length for the elbows and then use this friction factor to determine friction loss.