How graphing contours of expression

starry09 · January 30, 2020, 01:47

Hi,

Please let me know how to figure out the contours of expressions that I define.

Светлана · January 30, 2020, 20:09

How do you define the expression?
Can you define it as Custom Field Function?

starry09 · February 3, 2020, 22:04

Quote:

Originally Posted by Светлана

How do you define the expression?
Can you define it as Custom Field Function?

I am working on 2019R3 where expressions could be definitely named.

My question is how to get the contour graph of the defined expressions?

For example, I tried to make a report on those variables or expressions, but the error messages were just pop up, 'expression is not single-valued,' or 'Syntax invalid.'

starry09 · February 4, 2020, 08:35

In post-processing, the defined expressions can be set as the user-defined variables, which can allow users to generate contour graphs.

On the contrary, it looks like that Fluent (2019R3 ver.) helps define easy expressions alternative to UDF, but I have little knowledge in setting the expressions as the variables and graphing its contours.

https://www.dropbox.com/s/6eaufffttn...Setup.png?dl=0

vinerm · February 4, 2020, 09:50

Fluent Expressions Language is based on CFX Expression Language. CFX does not allow plotting of field expressions. You have to assign it to an additional variable to plot it. Its same in Fluent. Create a UDS and then assign the expression to UDS. Then you can plot UDS.

starry09 · February 6, 2020, 01:20

Quote:

Originally Posted by vinerm

Fluent Expressions Language is based on CFX Expression Language. CFX does not allow plotting of field expressions. You have to assign it to an additional variable to plot it. Its same in Fluent. Create a UDS and then assign the expression to UDS. Then you can plot UDS.

Thanks, vinerm

I finally found out that 'custom field function (CFF)' can lead to the contour graphing.
Could you let me know which differences between CFF and expressions are?

vinerm · February 6, 2020, 03:51

CFF and expressions are pretty similar, however, when it comes to usage, expressions are more powerful. Expressions have been borrowed from CFX and can be used for purposes where CFF cannot be used, such as to apply a boundary condition profile or may be even a property.

starry09 · February 10, 2020, 01:10

Quote:

Originally Posted by vinerm

CFF and expressions are pretty similar, however, when it comes to usage, expressions are more powerful. Expressions have been borrowed from CFX and can be used for purposes where CFF cannot be used, such as to apply a boundary condition profile or may be even a property.

Thanks a lot.

nagaanvesh · March 13, 2024, 17:22

in fluent software : while iam adding material properties data in a piecewise-linear way:

Cannot plot expression: Expressions of type Unknown are currently not plottable. Only expressions of type Double are plottable. i found this error.

Would you please anyone help me to clear this error ?

January 30, 2020, 01:47	How graphing contours of expression	#1
starry09 New Member SM Join Date: Dec 2018 Posts: 19 Rep Power: 7	Hi, Please let me know how to figure out the contours of expressions that I define.

February 4, 2020, 08:35		#4
starry09 New Member SM Join Date: Dec 2018 Posts: 19 Rep Power: 7	In post-processing, the defined expressions can be set as the user-defined variables, which can allow users to generate contour graphs. On the contrary, it looks like that Fluent (2019R3 ver.) helps define easy expressions alternative to UDF, but I have little knowledge in setting the expressions as the variables and graphing its contours. https://www.dropbox.com/s/6eaufffttn...Setup.png?dl=0 Светлана likes this.

February 4, 2020, 09:50	Same as CFX	#5
vinerm Senior Member Vinerm Join Date: Jun 2009 Location: Nederland Posts: 2,946 Blog Entries: 1 Rep Power: 35	Fluent Expressions Language is based on CFX Expression Language. CFX does not allow plotting of field expressions. You have to assign it to an additional variable to plot it. Its same in Fluent. Create a UDS and then assign the expression to UDS. Then you can plot UDS. Светлана likes this. __________________ Regards, Vinerm PM to be used if and only if you do not want something to be shared publicly. PM is considered to be of the least priority.

February 6, 2020, 03:51	Difference	#7
vinerm Senior Member Vinerm Join Date: Jun 2009 Location: Nederland Posts: 2,946 Blog Entries: 1 Rep Power: 35	CFF and expressions are pretty similar, however, when it comes to usage, expressions are more powerful. Expressions have been borrowed from CFX and can be used for purposes where CFF cannot be used, such as to apply a boundary condition profile or may be even a property. Светлана likes this. __________________ Regards, Vinerm PM to be used if and only if you do not want something to be shared publicly. PM is considered to be of the least priority.

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January 30, 2020, 20:09		#2
Светлана Senior Member Svetlana Tkachenko Join Date: Oct 2013 Location: Australia, Sydney Posts: 407 Rep Power: 14	How do you define the expression? Can you define it as Custom Field Function?

March 13, 2024, 17:22		#9
nagaanvesh New Member anvi Join Date: Jun 2021 Posts: 2 Rep Power: 0	in fluent software : while iam adding material properties data in a piecewise-linear way: Cannot plot expression: Expressions of type Unknown are currently not plottable. Only expressions of type Double are plottable. i found this error. Would you please anyone help me to clear this error ?