I want to know meaning of CFX Expression Language for numerical analysis of plasma.

Won-Ho Lee · March 10, 2020, 07:41

I am now conducting an analysis of thermal plasma.
But I don't know the meaning of CFX Expression Language as follows.
Please teach me the meaning of CFX Expression Language.

-Ignition Factor: 1e7[W*m^-3*K^-1]*ShapeRad*step(50-aitern)*step(aitern-10)*step(Ignition Target-T)
-Igntion Source: Ignition Factor*(Ignition Target-T)
-NetEmission: 3000[W*m^-3]*(exp(FNetEmission*T)-exp(FNetEmission*30[C])

karachun · March 10, 2020, 09:06

Read Chapter 13: CFX Expression Language (CEL) and Chapter 14: Functions in ANSYS CFX of Ansys CFX Reference Guide. These chapters contain everything you need to know about CFX Expressions.
You can download Reference Guide here:
http://read.pudn.com/downloads500/eb...64/cfx_ref.pdf

Won-Ho Lee · March 12, 2020, 20:52

Thank you for your answer.
Howerver, I want to know physical meaning about CFX Expression language(Especially, Ignition Factor).

ghorrocks · March 13, 2020, 00:49

CFX Expression language is just a way of defining functions and accessing data out of CFX. To learn CFX Expression language refer to the CFX Reference Guide.

But I have no idea what the "Ignition Factor" variable you defined is. You defined it, so it is what you defined it to be. Or if you got the equation from somebody else then ask whoever you got it from.

karachun · March 13, 2020, 02:16

This is just expression name. You can rename "Ignition Factor" to "Lalala", replace everywhere in project "Ignition Factor" with "Lalala" and everything work fine. It is not something hardcoded into CFX.
You should ask person who create these expressions about expressions logic.
Finally these expressions are incomplete, these expressions refer to other user expressions, like ShapeRad and FNetEmission. Without them expressions didn`t work at all.

March 10, 2020, 07:41	I want to know meaning of CFX Expression Language for numerical analysis of plasma.	#1
Won-Ho Lee New Member Won-Ho Lee Join Date: Oct 2018 Location: South Korea Posts: 2 Rep Power: 0	I am now conducting an analysis of thermal plasma. But I don't know the meaning of CFX Expression Language as follows. Please teach me the meaning of CFX Expression Language. -Ignition Factor: 1e7[Wm^-3K^-1]ShapeRadstep(50-aitern)step(aitern-10)step(Ignition Target-T) -Igntion Source: Ignition Factor(Ignition Target-T) -NetEmission: 3000[Wm^-3](exp(FNetEmissionT)-exp(FNetEmission*30[C])

March 13, 2020, 00:49		#4
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,703 Rep Power: 143	CFX Expression language is just a way of defining functions and accessing data out of CFX. To learn CFX Expression language refer to the CFX Reference Guide. But I have no idea what the "Ignition Factor" variable you defined is. You defined it, so it is what you defined it to be. Or if you got the equation from somebody else then ask whoever you got it from. __________________ Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.

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March 10, 2020, 09:06		#2
karachun Senior Member Join Date: Nov 2015 Posts: 244 Rep Power: 11	Read Chapter 13: CFX Expression Language (CEL) and Chapter 14: Functions in ANSYS CFX of Ansys CFX Reference Guide. These chapters contain everything you need to know about CFX Expressions. You can download Reference Guide here: http://read.pudn.com/downloads500/eb...64/cfx_ref.pdf

March 12, 2020, 20:52		#3
Won-Ho Lee New Member Won-Ho Lee Join Date: Oct 2018 Location: South Korea Posts: 2 Rep Power: 0	Thank you for your answer. Howerver, I want to know physical meaning about CFX Expression language(Especially, Ignition Factor).

March 13, 2020, 02:16		#5
karachun Senior Member Join Date: Nov 2015 Posts: 244 Rep Power: 11	This is just expression name. You can rename "Ignition Factor" to "Lalala", replace everywhere in project "Ignition Factor" with "Lalala" and everything work fine. It is not something hardcoded into CFX. You should ask person who create these expressions about expressions logic. Finally these expressions are incomplete, these expressions refer to other user expressions, like ShapeRad and FNetEmission. Without them expressions didn`t work at all.