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August 24, 2013, 10:30 |
sutherland law?
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#1 |
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TPRPR1
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hi
i have a question regarding the Sutherland law for air s=110 mo=1.715 t0=273.11 does the co-efficients vary with altitude of air? for example for 10000m mo=1.458e^-5 how do i calculate S? thanks in advance Last edited by tprpr1; August 24, 2013 at 13:33. |
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August 27, 2013, 05:37 |
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#2 |
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Ehsan
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Hi
whats "mo"? didn't you get anything by searching?
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August 27, 2013, 06:49 |
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#3 |
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TPRPR1
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s=sutherland temperature
m0=reference viscosity to=reference temperature i looked at several places on the net to=remains the same for all s and m0 changes for different materials However mo will change for different altitude for air(data available) but i do not know how to calculate s corresponding to the new mo |
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August 27, 2013, 07:23 |
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#4 |
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Lefteris
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http://www.cfd-online.com/Forums/mai...rland-law.html
Anderson too in the Fundamentals of Aerodynamics 5th Edition, gives S=110
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August 27, 2013, 08:42 |
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#5 |
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Hi, I would say that for a certain fluid the coefficients are constant, viscosity only changes with temperature. The viscosity of air varies indirectly with altitude through temperature.
Cheers, Michujo. |
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August 27, 2013, 09:19 |
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#6 |
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Lefteris
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If you take air to be an ideal gas
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Lefteris |
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August 27, 2013, 13:14 |
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#7 |
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Hi, can you please elaborate?
Thanks, Michujo. |
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August 27, 2013, 13:20 |
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#8 |
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Lefteris
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I hadn't read carefully your post and I didn't know how to delete my post
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Lefteris |
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August 27, 2013, 15:26 |
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#9 |
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TPRPR1
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thank you all for replying
so in other words the 3 coefficients mo ,to,s remain the same for any altitude as long as im taking air as ideal gas in fluent the actual viscosity m will vary as a function of temperature t. that clears my doubt .thank you |
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