Error id: 2150 in buckling topology optimization (massfrac)

Altair Forum User

I'm doing an optimization where I put the response as DRESP1 massfrac. In dconstraints, selected lower bound = 0,6 and upper bound = 0,7 and the following error appears in the solver:

 

*** ERROR # 2150 ***

 Invalid Volume or Mass Constraint.

 The response type is the total MASSFRAC

 the upper bound value =   7.000000E-01

      the total volume =   1.805255E+05

     the design volume =   1.660834E+04

        the total mass =   1.426151E-03

       the design mass =   1.312059E-04

 The design material fraction (percent) should be at least 3 times

 the DOPTPRM MINDENS (default 0.01)

 

 

 

Solver FAILED

 

optistruct:: Solver run finished.

 

Could anyone help me? 

Thanks

 

Altair Forum User

Hi felipeds

 

This is because the available design mass that can be used is either near zero or negative.

 

Can you try to relax the upper bound and check?

 

also, check the unit consistency in your model.