Solid metal duct pipe vs. flexible, ribbed pipe

[Treevly]

Even with the ribbed pipe fully extended, there is still a certain amount of texture which the air must flow through. Has anyone any knowledge as to whether or not there exists a comparison of airflow and constriction in the two types?
Thank you.

 

[I'mback]

a metal pipe will create a "laminar flow" (what we want) vice a turbulent one which exist with ribbed flex pipe. I grow in a tent but if I wanted a permanent set up, I would be using straight ducting

 

[GOT_BUD?]

There's a reason why the ducting in your house is sheet steel and not flexible, and it's not because the steel is easier to work with.

 

[Treevly]

Thank you, thank you.

 

[f-e]

Most hvac books have the pressure drop expected from just about everything. If they don't, you can't design anything to use it. So expect all sorts of duct, with measurements per meter. Along with any other fittings you might have. A standard 90 could be worth a few meters of straight run. It's all there in the design books, and quite interesting for everyone to look at. Though maybe just once.