Fluid Property Error?

Forum about flow calculators available on pipeflowcalculations.com and how to find solution for your fluid flow problem.
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dmon53
Posts: 3
Joined: Thu May 31, 2012 5:14 pm

Fluid Property Error?

Post by dmon53 »

I have been using you Pressure drop and flow rate calculator for a cooling problem on our hydraulic system (very nice - thanks for your efforts). The cooling system is spec'd at 20 GPM min (chill water temp is about 60 deg F) and is supplied by about 5 ft of 1" copper pipe connected to a 2" header. I wanted to see what the drop (header pressure is about 21 psi) would be across the 5ft of 1"pipe so I plugged in everything and not realizing it I didn't change the units on the viscosity. I came up with a value that I pretty much expected (just under 1 psi drop). Then I noticed that the viscosity units was set to mm2/s. Your chart says that at 10 deg C (close enough) v=1.306 m2/s. If I change the units I get an astronomical value for pressure drop (35,643 psi drop). Mu and Nu seem to correlate but be off by a factor of 1000.
Is this an error or am I not understanding something?
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admin
Site Admin
Posts: 375
Joined: Mon Feb 08, 2010 7:47 pm

Re: Fluid Property Error?

Post by admin »

Please note the in the table viscosity is v*10^6=1.306m2/s, so it is actually v=1.306 mm2/s.
Pipe flow calculations - since 2000
dmon53
Posts: 3
Joined: Thu May 31, 2012 5:14 pm

Re: Fluid Property Error?

Post by dmon53 »

Sorry for the oversight. These calculators have been a great help. Thanks.
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