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).

Enrico_20294

Sorry, I can't understand

Please find attached the model I'm using

What is the difference  with a classic buckling problem?

Thanks for your patience

 

Enrico

Unable to find an attachment - read this blog

Altair Forum User

Hi,

I think that shouldn't affect your results.

Anyways,  Can you update to latest solver patch?

 

I dont see that information with 2017.2.2 solver update

Enrico_20294

How can update to latest solver patch?

I think I have the version 2017.2

Altair Forum User

Hi,

 

Go to https://connect.altair.com/CP/downloads.html Login and download the latest patch for HyperWorks solvers.

<?xml version="1.0" encoding="UTF-8"?>

Enrico_20294

Thank you so much!

Enrico