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August 12, 2016, 07:09 |
Error in defining expression
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#1 |
Senior Member
Aja
Join Date: Nov 2013
Posts: 496
Rep Power: 14 |
Hi,
I am defining an expression, but i have a error as follows: Why does this happen? Thanks. Last edited by aja1345; August 16, 2016 at 08:06. |
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August 12, 2016, 07:24 |
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#2 |
Senior Member
urosgrivc
Join Date: Dec 2015
Location: Slovenija
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What does this mean? )(
try )*( multiplication if this is what you want? |
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August 12, 2016, 07:34 |
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#3 |
Senior Member
Aja
Join Date: Nov 2013
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August 12, 2016, 09:10 |
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#4 |
Senior Member
Aja
Join Date: Nov 2013
Posts: 496
Rep Power: 14 |
Hi,
Why does the following error happen? I want to define gas constant of air. Last edited by aja1345; August 16, 2016 at 08:05. |
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August 12, 2016, 10:07 |
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#5 |
Senior Member
Aja
Join Date: Nov 2013
Posts: 496
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Why does unit of the following expression equal to Kg^2 m s^-5 K^-2?
volumeInt(((Thermal Conductivity/(Temperature)^2)*((1/(Density*(R/(M air))))*(Pressure.Gradient X)^2+(1/(Density*(R/M air)))*(Pressure.Gradient Y)^2+(1/(Density*(R/M air)))*(Pressure.Gradient Z)^2)))@Rotary R=gas constant According to above, Unit of Volume integral should be equal to kg m^2/S^-3 K^-1 . I assumed fluid as ideal gas presently. therefore>>>>> P=Ro*R*T T=P/(RO*T) ......... Thanks. Last edited by aja1345; September 7, 2016 at 12:11. |
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August 14, 2016, 14:08 |
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#6 |
Senior Member
urosgrivc
Join Date: Dec 2015
Location: Slovenija
Posts: 365
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I dont think that [Kj] means enithing.
definitly not with smal j I am asking the experts now-> (is kilo(k) , mega(M) and other prefixes suported instead of multipliers) as I havent tried it out myself. Joul=J should work but than, for Kilo you should multiply it by 1000. so you would end up with [J kg^-1 K^-1]*1000 |
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August 14, 2016, 19:31 |
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#7 |
Super Moderator
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
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Yes, CFX supports the SI unit system with prefixes. But you have to get it correct, as urosgrivc states. Joule is J and kilo prefix is k, so the unit if kJ.
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August 15, 2016, 07:15 |
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#8 |
Senior Member
Aja
Join Date: Nov 2013
Posts: 496
Rep Power: 14 |
Thanks.
What is your suggestion about defining expression? I am grateful that guide me about this case. Last edited by aja1345; August 16, 2016 at 08:08. |
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August 15, 2016, 07:41 |
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#9 |
Super Moderator
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,746
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I think the temperature gradient functions work in CFD-Post. Have a look in the CFX reference manual for a description of the available variables and functions you can apply to them.
Also the temperature gradient variables will be available under the puzzlingly titled "..." button for plotting on surfaces, vectors etc. |
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August 15, 2016, 15:28 |
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#10 |
Senior Member
Aja
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August 15, 2016, 15:42 |
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#11 |
Senior Member
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Insert an User Defined Variable, for the method select Gradient, and select Temperature for the variable. CFD-Post will create the Temperature.Gradient variable.
You can then use it as needed. |
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