Quote:
Originally posted by unregistered
Alchemy
do not assume fittings are negligible (this is a repeat message)
unless the system has no fittings
get a copy of Crane #410, but similar stuff is in the textbooks
a single single mitre 90 will have an effect, and is of no benefit to cooling
or perhaps you wish to show by calculation what 'negligible' means to you
- pHaestus' article is a good starting point, and I can give you some rad and wb flow curves if you cannot use those that are posted
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Alright, clearly you want a program more precise than the one I imagine. That's fine.
My idea was to take the PQ curves for the various blocks and rads and combine them, then use the correlation with that curve to the pump curve to get the flowrate.
If you want to add more items in there, you'd want to design PQ curves for various fittings. Items that you probably don't have empirical correlations for - reservoirs and airtraps like the one in pHaestus's article where there is significant loss of energy due to chaotic flow - will have effects as high or higher than elbows and tees. These can't be correlated with Darcy or Moody.
So, does anyone have roughness coefficients for silicon tubing and form friction factors for specific fittings, then? They do vary by design, size, and manufacture, sometimes by quite a bit.
Alchemy