Exhaust Duct

Your questions indicate that you will not be designing a duct. You seem to be wanting someone else to do the design work.

You don't know how to size the duct, nor what material to use, so I'd call you a drafter, not a designer.

Just seems strange to me that you say you are designing something, but have no idea how to begin, nor what material to use.

Happy to let you expert designers take it from here!

Good luck.

Why not start with the specific engine manufacturer criteria for maximum exhaust restriction. This will help with your calculations....

Then, you may consider calculating the restriction your co-generation unit will add to your exhaust.

Then lets calculate the specific engines exhaust duct as it is presently, most that are square or rectangular in shape, eventually go to a transition and then onto normal grade pipe. I have seen both sch 40 and 80 in use on medium speed units up to 6000 kw.

You really need to be more specific and offer more information to receive any useful information.

Tim

ok thanks, you put me on the right track.

i have the Maximum Allowable Back Pressure [it is the same max restriction]

one more question, when i am calculating the losses in the duct, i use the same method to when i am calculating the losses in normal duct for normal ventilation or AC duct ?

big thanks

Back Pressure is one in the same as restriction, yes.

I am very sorry for not being able to actually help you calculate your duct losses. This goes onto one of the smarter guys in the forum once you list all your information properly I am sure someone may help you.

Good Luck

Tim