Ansys thermal contact not working

[tonyel]

I've made a model with conta174 and targe170 elements to tie together layers with dissimilar meshes. I thought it had worked fine, until, as a check, I compared it with a simplified model which had the layers glued together and meshed as one. The results were totally different. Has anyone any experience of such issues with thermal contact?

 

[Stringmaker]

Is your contact closed?

 

[tonyel]

Yes - keyopt 12 set to 5, which I believe should mean that they are always bonded.

 

[cbrn]

Hi,
also check that KEYOPT1=1 or 2 (depending on your analysis type), and that you have Real Constant 14 "TCC" Thermal Contact Conductance set to the appropriate value.

Regards

 

[tonyel]

Yep - set Keyopt 1 to 2. I've tried this all sorts of different ways, and sometimes it seems to work and other times not. The strange thing is that, although at first glance it seems to have worked fine, the results are not correct. There is some heat flow across the contact layer, but the actual results don't match my test model. I've set the conductance to 100 000 (real constant 14 set at 100 000) in units of W/mm2K, which should be pretty close to perfect conductivity.

 

[Stringmaker]

Is keyopt 5 set to 3 or 4? When you issue the CNCHECK command does contact status indicate it is closed? Bonded contact doesn't mean it's closed.