Assembly, differing areas

I'm running a thermal analysis with contact between two surfaces. The surfaces are slightly different areas and Code_aster is complaining about this.

I'm sure I've previously running mechanical analysis with contact areas that didn't tally precisely.

Is there a way around this, or a simple way of reducing one mesh group so that it matches the other? The mesh group was created from the geometry, so directly selecting the appropriate surfaces.


Thanks
Joe

Some progress.

So face_1 on solid_1 contacts face_2 on solid_2. I've partitioned solid_2 using face_1 as a tool, so I can now specify a face on solid_2 that matches exactly with face_1.

However I'm still getting differing meshes on the two faces so it still won't run it.

[code:1] LOADING=AFFE_CHAR_THER(INFO=1,
FLUX_REP=_F(GROUP_MA='heat_in',
FLUN=3.7000E4),
ECHANGE_PAROI=_F(GROUP_MA_1='mnt_cont',
GROUP_MA_2='bot_cont',
COEF_H=3000.0),
ECHANGE=_F(GROUP_MA='bot_air',
COEF_H=5.5999999999999996,
TEMP_EXT=20.0),
MODELE=MODEL,
);


!

---

!
! <EXCEPTION> <MODELISA6_22> !
! !
! !
! les 2 listes &&CAECHP.LLIST1 et &&CAECHP.LLIST2 ne sont pas de meme longueur !
! !
! !
! !
! !
!

---

![/code:1]

Google says 'the two lists are different lengths.'

I've also created a submesh on each of the two faces, but the resulting face groups still have a different number of nodes.

How can I force it to create matching meshes on these faces?<br /><br />Post edited by: Joe Dowsett, at: 2010/12/09 21:33

Problem solved, mostly.

To fix the meshing issue, I fused the two solids and then partitioned it. The two mating faces now have the same number of mesh elements.

For some reason it can't find a stationary solution, not sure why as it's a simple case of a little heat in, and a large air surface to lose heat to.

Never mind, at least I'm getting something now and shall hopefully figure out the stationary thing soon.