Subject: seeking help with solving implicit equation
From: Len de Vlaming
Date: Fri, 25 Jan 2008 09:12:25 -0800
Folks,
I'm writing a routine which makes use of the Colebrook equation for
calculating friction factors:
1/sqrt(f) = -2log(e/3.7D + 2.51 / (Re*sqrt(f))
In other words, the equation is implicit in the friction factor f.
How do I properly define the equation and solve for f once I have
defined e, D, Re? I thought it was as simple as
1/sqrt(f):= ..etc.., define the other variables via the : operator and
solve (%,f) but this makes Maxima swear at me. It seems like this
should be fairly straightforward root finding, but then again I am not a
mathematician and there's likely some fundamental problem staring me
full in the face.
A clue for the clueless?
Thanks
Len
Len de Vlaming
Project Consultant
Geomatrix Consultants
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