shell buckling - *** INFORMATION # 3454

Enrico_20294

Hello,

I'm trying to perform a linear buckling analysis on a hemisphere subjected to external pressure and constrained at the base.

Running the analysis, in the .out file I find:

*** INFORMATION # 3454
 MPC constraints for subcase 2 will be enforced  with lagrange multipliers.

 

Could you please explain what does it mean?

Thank you so much for your kindess

 

Enrico

Altair Forum User

Hi Enrico,

 

From help:

Constraint nonlinearity in a system can occur if kinematic constraints are present in the model. The kinematic degrees-of-freedom of a model can be constrained by imposing restrictions on its movement. In OptiStruct, constraints are enforced with Lagrange multipliers (Constraint reduction).