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Navier stokes and maxwell slip boundary

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Old   August 3, 2013, 01:43
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Mr.Alex,

The boundary conditions look correct in the way you said . May be the Maccormack method which i wrote is responsible for the errors i guess. Have you tried implementing this with the navier stokes ? . If so could you check on my entire code ?
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Old   August 3, 2013, 02:38
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For NS, i only have a small 1-dimensional (+incompressible +isothermal) code with finite differences.
I guess you will have to go the usual way by debugging your code step by step.
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Old   August 5, 2013, 13:29
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Thanks for the help Alex . I will start debug my code and find out any errors that prevents me to go further .
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Old   August 20, 2013, 17:52
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Quote:
Originally Posted by flotus1 View Post
For NS, i only have a small 1-dimensional (+incompressible +isothermal) code with finite differences.
I guess you will have to go the usual way by debugging your code step by step.
Mr.Alex ,

I recently found that my code over predicts the results . Could you help me with this ? . I dont know what is wrong with this . The results for no slip condition too is over predicted for certain plots .

thanks in advance
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Old   August 21, 2013, 02:26
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When you say your results are over-predicted, what exactly do you mean?
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Old   August 21, 2013, 02:29
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I get exactly same graphs as in t book . but slight variation in t peak values . For example , p/pinf =1.45 (from book) , p/ping=1.6 (from my code)
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Old   October 13, 2013, 23:46
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Quote:
Originally Posted by flotus1 View Post
For NS, i only have a small 1-dimensional (+incompressible +isothermal) code with finite differences.
I guess you will have to go the usual way by debugging your code step by step.
Mr Alex ,

This is the temperature plot i got for Kn=0.0156 . But when i tried the same method with kn=0.0723 . It just blows away giving complex numbers . after 7 steps. But actually this range of knudsen number falls into slip regime right ? The input conditions are as follows

Alt=10km

Pinf=2.65e4;
T=223.2625;
Kn=0.0156

Alt=20km
Pinf=5.523e3;
T=216.65
kn=0.0723
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