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kmgraju September 18, 2010 15:55

Help needed for writing CEL expression
1 Attachment(s)
dear all

I am facing difficulties in writing CEL expression for my problem

Please see the attached expressions
here a,b,c, and d are constants .but it is not valid if i write the expression in exponential form. Kindly explain to me
but if I introduce [s^-1] for all constants I am getting plot.
and in the final expression also i am facing difficulties . Please help me. what mistake I did?
Thanks in advance

ghorrocks September 19, 2010 05:59

Obviously you need to use units s^-1 for the expression to be valid. Expressions like exp and ^ need unitless inputs. Hopefully you can work it out from there.

kmgraju September 19, 2010 09:58

Thank you for your valuable guidelines
Actually I am trying to do the analysis of non Newtonian fluid flow.
I tried to do tutorial problem Non Newtonian fluid flow in an annulus
I didn't find other models other than Sutherlands Formula . I could not find Ostwald de Waele model as stated in the tutorial problems
Please help me where can I find this information or is the installation not full?
I also couldn't find other models like Bird Carreau,Casson and so on
Thank you so much


ghorrocks September 19, 2010 18:49

All those models are in there. Set Kin Viscosity to Non-Newtonian and those options become available.

kmgraju September 20, 2010 02:49

1 Attachment(s)
Dear Mr. Glenn Horrocks

I am using ANSYS CFX 11. I have attached the front screen for your kind perusal. I couldn't find non Newtonian fluid option

Thanks in advance

ghorrocks September 20, 2010 18:30

Then either it was introduced in V12 or you need an upgraded license to access it. Not sure which. Either way it is time for an upgrade. Talk to CFX support.

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