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Reynolds nos verification

Posted: Sat Sep 18, 2010 8:35 am
by gnikomson2000
Could somebody confirm or negate these Reynolds numbers? The Object is a ethanol still, a twin outlet (Tee fitting) vapor conduit of variable diameters, fed from a boiler which generates the vapor. The vapor speeds are known and correct. I just need clarification of the Re nos relative to pipe diameters.
vapor%20speeds.JPG
vapor%20speeds.JPG (41.89 KiB) Viewed 7034 times
Thanks in advance

Re: Reynolds nos verification

Posted: Sun Sep 19, 2010 6:12 pm
by admin
Do you know viscosity of fluid in given positions?

Re: Reynolds nos verification

Posted: Sun Sep 19, 2010 11:18 pm
by gnikomson2000
Administrator wrote:Do you know viscosity of fluid in given positions?

The fluid is ethanol-water vapor assumed to be azeotropic at all points. Azeotrope is 89 mole-% ethanol and 11 mole-% water, or roughly 96% & 4% by volume. Below is the chart I have for properties of the pure (100%) substances...
Ethanol-Water Properties.jpg
Ethanol-Water Properties.jpg (77.02 KiB) Viewed 7028 times

Many thanks for any input.

Regards Harry

Re: Reynolds nos verification

Posted: Tue Sep 21, 2010 6:59 am
by admin
With these values for viscosity you can use equation for mixtures at:
http://www.pipeflowcalculations.com/pip ... cosity.htm

And with mixture viscosity, you can calculate Re number using:
http://www.pipeflowcalculations.com/reynolds/index.htm
above calculator.

Re: Reynolds nos verification

Posted: Tue Sep 21, 2010 11:06 pm
by gnikomson2000
Thank you for pointing me in the right direction

Regards Harry