Error during analysis - Optistruct

Altair Forum User
Altair Forum User
Altair Employee
edited November 2020 in Community Q&A

Hallo , 

 

I planned to implement the BC, Load cases what is exactly in ( Link Provided) in to my model which is already topologically optimized . I applied all the details that are provided and I am getting the following error , Could anyone please provide or check how to rectify the error. I would like to do linear static analysis with my approach in this already topologically optimized model. Thanks in advance . Here with I showed what the error is and also my hm file for your reference .

  Quote

 *** WARNING 1931:      SPC SID=   4 is not referenced by Case Control.
  
 *** WARNING # 1848
 Topology optimization without minimum member size control activated.
 Using DTPL card or DOPTPRM,MINDIM is recommended.
  
 NOTE # 1852
 AUTOMATIC SCREENING is activated.
 Use DSCREEN,AUTO,OFF to disable automatic screening.
  
 *** ERROR # 339 ***
 The dependent d.o.f. is constrained by grid or spc data.
 RBE3 element id = 34776.
         grid id = 6689.
       component = 2.
  
 *** ERROR # 339 ***
 The dependent d.o.f. is constrained by grid or spc data.
 RBE3 element id = 34777.
         grid id = 6690.
       component = 1.
  
 *** ERROR # 329 ***
 RBE3 element 34779 cannot support a x-moment - check element data.
  
 *** ERROR # 330 ***
 RBE3 element 34779 cannot support a y-moment - check element data.
  
 *** ERROR # 331 ***
 RBE3 element 34779 cannot support a z-moment - check element data.
 Number of bad RBE3 elements =        3

Unable to find an attachment - read this blog

Answers

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited April 2017

    @muthu62

     

    Create RBE2 instead of RBE3 and try again. 

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited November 2020

    @Prakash Pagadala Thanks for your info and as  you said I used RB2 for all three non-design component. But now i am getting element quality error. I checked in element quality tab ( warpage , jacobian is 0 error only with skew angle and tet collapse I am getting some error ) I am getting error because of this problem or something else . would be much appreicated if you say . Thanks in advance and for your reference i attached out file and also the updated hm file .

     

    Kind Regards, 

    Muthu.

    Unable to find an attachment - read this blog

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited April 2017

    Hi Muthu,

     

    You can by pass element quality check by setting PARAM>>CHECKEL>>NO

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited April 2017

    Hallo Mr.Prakash , 

    Thanks for your valuable info and it worked , I could run my model and with no ERROR. I would like to run only linear - Static Analysis not OPTIMIZATION so when I tried to run my model in hyperview for frame 0 it shows and for the subsequent frames its not showing properly . Could you take a look for a minute and check wat might be the problem . I think if i make it then i can finish up this work and thanks for your previous assist :)/emoticons/default_smile.png' srcset='/emoticons/smile@2x.png 2x' title=':)' width='20' /> . For your reference attached the fem file so you can directly look in Hyperview . Anticipating your positive response .

     

    Kind Regards,

    Muthu. 

    <?xml version="1.0" encoding="UTF-8"?>mesh0.008.jpg

    Unable to find an attachment - read this blog

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited April 2017

    Hi Muthu,

     

    Can you check the dimensions?

     

    Looks like there is some problem with model dimensions.

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited April 2017

    Hallo Mr.Prakash,

    The Dimension of the model is defined already , because it is already topologically optimized model I cant refine or redo any changes in to that . I want to do Linear -Static analysis in this model by different mesh refining methods. Will it be any other problem like the way I approached ? or if this is only because of the given model . By the way thanks alot for your valuable info .

     

    Kind Regards, 
    Muthu.

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited April 2017

    Muthu,

     

    If you look at the length of the component it is around 0.2mm and mass is 1.3e-11 tonnes which looks impractical for such a component.