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How to map temperatures/heat flux onto a thermal model

How to map temperatures/heat flux onto a thermal model

How to map temperatures/heat flux onto a thermal model

(OP)
Ok, so I'm using Ansys Workbench, and I'd like to map temperatures and heat flux onto portions of my model as boundary conditions which vary with the x-coordinate. The distributions are not constant or linear, so the GUI tools seem to be insufficient. I've written a few "Command Object" scripts, but they don't seem to map all of the values that I input and I can't figure out why. The temperature mapping script below stops mapping at 378.3C and applies a constant temperature along the remaining length of the surface:

*DIM,temp_table,table,29,,,x
temp_table(1,0)= -0.0767, -0.0752, -0.0737, -0.0722, -0.0707, -0.0692, -0.0677, -0.0661, -0.0646, -0.0631, -0.0616, -0.0601, -0.0586, -0.0571, -0.0556, -0.0540, -0.0525, -0.0510, -0.0495, -0.0480, -0.0460, -0.0440, -0.0420, -0.0400, -0.0381, -0.0361, -0.0341, -0.0321, -0.0301
temp_table(1,1)=   745.5,   728.8,   711.5,   693.6,   675.1,   655.9,   636.2,   615.8,   594.8,   573.2,   551.0,   528.2,   504.7,   480.7,   456.0,   430.7,   404.8,   378.3,   351.2,   323.5,   282.3,   245.1,   211.7,   181.9,   155.6,   132.7,   112.9,    96.0,    82.1
d,regen_wall,temp,%temp_table%

I've written a similar script for mapping heat flux boundary conditions, but when I query the results, the heat flux doesn't seem to match that which I intended to apply. In the solve.out file I get the following warning:

 *** WARNING ***                         CP =     795.062   TIME= 01:34:30
 Some of the defined and selected elements did not require heat fluxes.  
 Use the SFELIST,ALL,HFLU command to view a list of elements that did    
 have heat fluxes stored.

The script that I've written is as follows:

*DIM,acceptor_qtable,table,11,,,x
acceptor_qtable(1,0)=  -0.0917,  -0.0911,  -0.0897,  -0.0884,  -0.0871,  -0.0857,  -0.0844,  -0.0831,  -0.0817,  -0.0804,  -0.0797
acceptor_qtable(1,1)= -30823.5, -31093.2, -31353.2, -31627.1, -35983.1, -40342.5, -47240.3, -54139.1, -65194.2, -76253.5, -87312.4
sf,accept_pass,hflux,%acceptor_qtable%
sf,heater_head,hflux,-14804

I've looked at this thing six ways to Sunday, compared it with the Ansys documentation, and I can't figure out why it doesn't work properly. Any help would be greatly appreciated.
 

RE: How to map temperatures/heat flux onto a thermal model

(OP)
Just to give a quick update, I was able to map temperatures using a tabular temperature boundary condition GUI that is available in Workbench. I'm still unsure why the script doesn't work, though.
Also, I'm still getting screwy heat fluxes. Thanks in advance for any thoughts you have.

RE: How to map temperatures/heat flux onto a thermal model

I don't see an obvious problem with the commands for applying the temperatures.  You might try listing or plotting after defining the table to see that it was interpreted correctly.

As for the fluxes, it may be that some elements do not accept them -- this depends on the KEYOPT selections.

RE: How to map temperatures/heat flux onto a thermal model

(OP)
Thanks, I'll check the element options (although I don't think that Workbench calls them KEYOPTs - same difference).

I solved one problem: one of my heat flux boundaries had the x-values in the reverse order. Apparently Ansys doesn't like that. I'm still not getting the expected results, though. I'll keep you posted with what I find out.

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