[heke402]

Hi all,

I know there are some discussion on how to use Fluent Scheme to change boundary condition and I followed their instructions and made it work. Now the only question I have is if I define the boundary condition using UDF (DEFINE_PROFILE()) then what the format of the scheme should be? The scheme file I wrote is as the following

(define (changeboundary)
(cond

((and (>= (rpgetvar 'flow-time) 0.001) (<= (rpgetvar 'flow-time) 0.002))

(ti-menu-load-string "define/boundary-conditions/zone-type 10 wall"))
(else

(ti-menu-load-string "define/boundary-conditions/zone-type 10 mass-flow-inlet")

(ti-menu-load-string "define/boundary-conditions mass-flow-inlet 10 mass_flow y"))
)
)

where "mass_flow" is my UDF name. I tried several times by executing the scheme file at each time step but it looks like Fluent did not recognize the UDF I used to define the boundary.

[AlexanderZ]

(ti-menu-load-string "define/boundary-conditions mass-flow-inlet 10 \"mass_flow\" y"))

it is possible that in your code between 10 and mass_flow should be other setting, check through TUI

[vinerm]

TUI commands are sequential, i.e., you cannot miss anything in between. Full TUI commands changes from case to case, depending upon which models are enabled. A RANS based model with flow, without any other model enabled would require

def bc mfi 10 y y y y "functionname::libraryname" n 0 n y n n y 3.7 5

This command assumes that the library is already loaded. If it is not, then you have to load the library using

def user comp load "libraryName"

[heke402]

Hi AlexanderZ,

Thanks for the help! I checked through TUI and my issue has been solved.

[heke402]

Hi vinerm,

Thank you so much for the help! I have solved this issue by using the correct TUI command as you mentioned.

[heke402]

Dear AlexanderZ,

I have one more question. By looking up the TUI and answering all the questions, I found for my case the correct TUI commands should be

ti-menu-load-string "define/boundary-conditions mass-flow-inlet 10 yes yes yes yes "udf" "mass_flow::libudf" no 0 no yes"

However, when I typed "udf" in the console window to answer the question, there is no problem about it and Fluent can recognize what I typed. But when I wrote the TUI command into a scm file and execute the file at each time step during simulation, I always got an error as "Error: eval: unbound variable; Error Object :udf". I use ANSYS 16.0 and I am confused why Fluent can recognize "udf" in console window but can not do it in scm file. Could you please help me solve this issue, thank you in advance for your help!

[heke402]

Dear vinerm,

I have one more question. By looking up the TUI and answering all the questions, I found for my case the correct TUI commands should be

ti-menu-load-string "define/boundary-conditions mass-flow-inlet 10 yes yes yes yes "udf" "mass_flow::libudf" no 0 no yes"

However, when I typed "udf" in the console window to answer the question, there is no problem about it and Fluent can recognize what I typed. But when I wrote the TUI command into a scm file and execute the file at each time step during simulation, I always got an error as "Error: eval: unbound variable; Error Object :udf". I use ANSYS 16.0 and I am confused why Fluent can recognize "udf" in console window but can not do it in scm file. Could you please help me solve this issue, thank you in advance for your help!

[AlexanderZ]

use \" not "

[vinerm]

It depends whether you are using TUI within a ti-menu-load-string command or not. Since there is already double-quote opening the command, you have to escape the second one. So, command has to be

(ti-menu... "udf" "mass_flow::libudf" ...)

i.e., just use escape character before double quotes.

[vinerm]

Apparently, cfd-online is escaping is not displaying \ character before double-quotes. Use \ before every double quote and it will work.

[heke402]

Hi vinerm and AlexanderZ,

Thank you so much for your help! After adding escape character before double quotes, the problem has been solved.