Variable BC in time and space for transient run

April 12, 2006, 09:23

Dear all,

I want to set up a boundary conditions using a function with 2 variables using CFX-10 Pre. I know how to set up a function of one variable (space or time for ex.) by importing a text file (create user function), but I cannot find out how to impose a BC function of space AND time. Any help is highly appreciated! Thanks!!

Porry

KamilSobczak · February 20, 2012, 06:04

The same for me in Fluent

stumpy · February 21, 2012, 10:38

There's really no good way to do this in CFX. If you only have a few timestep, then you can set up a CEL expression that contains a series of if() statements all summed together, so different files get read at different timesteps. But that's not practical for many timesteps and it's not interpolating data in time, it's just using a different file at different timesteps.

April 12, 2006, 09:23	Variable BC in time and space for transient run	#1
Porry Guest Posts: n/a	Dear all, I want to set up a boundary conditions using a function with 2 variables using CFX-10 Pre. I know how to set up a function of one variable (space or time for ex.) by importing a text file (create user function), but I cannot find out how to impose a BC function of space AND time. Any help is highly appreciated! Thanks!! Porry

February 20, 2012, 06:04	UDF space AND time	#2
KamilSobczak New Member Kamil Sobczak Join Date: Jan 2010 Location: Warsaw, Poland Posts: 6 Rep Power: 16	The same for me in Fluent

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February 21, 2012, 10:38		#3
stumpy Senior Member Join Date: Apr 2009 Posts: 531 Rep Power: 21	There's really no good way to do this in CFX. If you only have a few timestep, then you can set up a CEL expression that contains a series of if() statements all summed together, so different files get read at different timesteps. But that's not practical for many timesteps and it's not interpolating data in time, it's just using a different file at different timesteps.