Singular pressure loss in a bend

1. Dec 6, 2016

Benoit0

Hello everyone,

I have difficulties estimating the singular pressure drop coefficient of a 90° bend of radius ratio 1.5, based on literature. For example, if I look at the Idel'Cik book, I find a value of 0.17. If I take a different reference: "TRW Fluid Designers Handbook", I get a coefficient of 0.6. If I take a look at a third reference: "Flow of fluids through valves, fittings, and pipe" (Crane), I get a different value (from a table not in function of radius / diameter but of the diameter...), and so on.
I cannot figure out which reference I should use and why?
Does anyone have an idea or an explanation why there are so many values?

Thanks a lot
Benoit

2. Dec 11, 2016