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-   -   IDEA viscosity (https://www.cfd-online.com/Forums/openfoam/86087-idea-viscosity.html)

mfmohdyasin March 14, 2011 07:33

IDEA viscosity
 
1 Attachment(s)
Dear all,
I tried to plot the Dynamic viscosity of different fuels that are implemented in OpenFOAM using the function given in NSRDSfunc1.H and the coefficients given in liquids/IDEA.C.

Based on the plot that I attached, IDEA dynamic viscosity increases after about 550K which is not physical. Does anyone know about this issue?

Best
Fairus

niklas March 14, 2011 11:54

Hmmm...I added that. I will look into it tomorrow.

niklas April 7, 2011 07:46

Its because the alphaMethyl napthalene properties are the way they are.
I have checked the numbers and they are correct as according to the NSRDS tables.

check the viscosity of aC11H10 and you will see how it looks.

for more info on how the idea fuel was constructed look into the file
src/thermophysicalModels/liquids/IDEA/IDEA.H

N

niklas April 7, 2011 07:50

looking into the table again I see that the valid temperature range for the liquid viscosity is only
250-450 K, which might explain the behavior.


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