Thermal Stress In Abaqus

[jester86403]

Hello all,

Recently I have been asked by my company to start learning abaqus. So I have been going throuugh some problems that have recently been solved by hand and trying to model them.

One thing I can't quite figure out is how to model a problem for thermal stress. My problem is a hollow cylinder where half of it is fit snugly into a rigid body and the other half is free. It is then subjected to a 40 degree temperature increase through out. I need to find the stresses caused by the expansion of the cylinder.

Can anyone help me out with this? I assume its a coupled thermal-displacement problem, but is it really a heat transfer problem in Abaqus? I'm really lost on it at this point.

 

[corus]

It's not a coupled thermal displacement or a heat transfer problem. As it's inside a rigid body you could have rotation at the end of the cylinder where it contacts the rigid body, so it resolves down to a hollow cylinder pinned at the end of the rigid body, subject to a temperature increase. Alternatively, it could be a cylinder built in at one end with a uniform temperature increase. There's a solution in Timoshenko's theory of plates and shells.

corus

 

[sharpedge]

Do you have a pictorial representation of what you are trying to model and I may be able to help out.

As Corus already mentioned, its not a coupled thermal-displacement problem unless there is an external force system acting somewhere alongside a change in temperature ( i.e thermal expansion/contrction) of some sort, then coupled thermal-displacement analysis is out of the question. Simply put, use thermal-stress or thermal-displacement coupling technique to solve for problems where the stress (mechanical input-force system, etc) is affected by the temperature and the temperature is affected by the stress (mechanical).

Modellnig problems for thermal stress, one obvious mistake is to forget to define coefficient of thermal expansion in your material mechanical properties definiton! Hence no change of internal state of consitutive material when there is a temperature rise.