My 2 cents,
Ra is the average roughness "The average height of the bumps on a surface, measured in micrometres or microinches".
From this to get the absolute roughness (to be used in the Colebrook-White expression) you simply have to calculate Ra/ID where Ra and ID have to be espressed with...
My dubt is: Can i use an oil to calculate an equivalent lenght, while in the real application the quick coupling is used with a gas (helium @20bar) ?
Thank you in advance
p.s. I don't have the Crane 401 :(
Fred
Hi all,
I'm tryng to calculate the pressure drop due to a quick coupling (Aeroquip) along an Helium high pressure line.
I have contacted the supplier, but he has not any information concerning the pressure drop due to their device; it gives me only data about pressure drop obtained with Mineral...