L2-norm Error 1

[YasserMamdouh]

Hi every one,

I am an electrical engineer, i have a problem in ansys, when i make solve > Current LS the following message appears:

"The L-2 norm of the residual force overflowed. This may be caused by PRED, ON or birth/dead elements. Please use PRED, OFF and try again."

My problem is in the field of Thermal analysis. And the loads are: Heat generation (Applied as Constant Value) and Convection (Applied as Function).

Please give me a prief solution for my problem and please explain the "L-2 norm".

Thanks

 

[lopessilva]

Hello,

The convergenge norm of the residual force (I think the force is your convergence criteria) is overflowed (is giving an extremely high number that does not allow its computation). This is commonly caused by the /PRED,ON value. If it´s the case, the value predicted by ANSYS is an extremely high value that does not allow computation. You should try to issue to /PRED,OFF command and see if it helps. If it does not help, the problem may be due to the mesh. The mesh may have been contaminated by other entities, mainly those originated from bolean operations, sucks as glue or overlap.To resolve this, try to mesh the model only after boolean operations are performed. To know exactly what the L-2 norm is, you should consult ANSYS help.

Hope I have helped,

Regards,
Hugo Silva
Mechanical Eng. PhD student
Materials Eng. MSc.