XANSYS Message: 34751 [Go back to message list] [bookmark on del.icio.us]
No rating yet Subject: Re: Regarding substructuring Author: Riccardo Testi Date: 2002-03-11 05:01:00Speaking about substructuring, I have a sort of philosophical question related to contact analysis: where does the border lie between a "do a superelement and then contact" and "do the contact only" strategies? When I have a huge model to be put in contact with something else, the question is "Will all the time I'll spend generating a superelement compensate the time I save during the subsequent contact analysis?"
Thank you very much
Riccardo Testi R&D and Operations 2 wheels/Engine Design Piaggio & C. spa v.le R. Piaggio, 25 - Pontedera (PI) - ITALY
At 22.53 08/03/02 +0000, you wrote: >I am giving total workspace as 1650 and db size 32. >I have very high end machine 2 GB ram 136 GB harddisk.
>Thanks
>Regards
>Somesh
>At 10:06 AM 08/03/2002 -0500, you wrote: > >Page file - what sort of -m and -db are you starting Ansys with?
> >Again we have a confusion. I have a big volume having 90000 elements. > >I have selected only boundary nodes those are around 3000. I have around > >9000master dof's. But the system is creating a huge page file and its not > >solving in the gereration pass.
> >Thanks
> >Regards
> >Somesh
> >At 09:04 AM 3/7/02 -0500, you wrote: > >> I don't understand "the frontal solver can solve only 50000 DOFs" - > >>there > >>is no such limit. Perhaps you mean what the solver can only handle 50000 > >>master DOFs? If so, this sounds like an extremely large number. Is it > >>possible > >>that you have set all DOFs to be masters rather than just some boundary or > >>loading nodes? > >>John Swanson > >>Swanson Analysis Services, Inc.
> >>> I have a single volume meshed with 50000 elements, I can not solve in > >>> generation pass, its coming out by giving watson error. Since the frontal > >>> solver can solve only 50000 DOF's. The problem is I can not divide the > >>> volume also. > >>> Again in the use pass, while solving its taking only frontal solver. But > >I > >>> need atleast sparse. I need an iterative solver in the use pass. How I > >can > >>> do it.
> >>> Thanks
> >>> Regards
> >>> Somesh
> >>> IEL, Hyd. > >>> India
> >>> At 08:01 AM 07/03/2002 -0500, you wrote: > >>> > A slightly longer answer is that substructure generation is a partial > >>> >factoring of the set > >>> >of equations, down to the set of Master DOFS. The other solvers in > >>> ANSYS, > >>> >both iterative > >>> >and direct, do not have this capability, which leaves you with the > >>> frontal > >>> >solver. > >>> > Direct solvers might be modified to have this capability (Sparse, > >for > >>> >example), but I have > >>> >not seen any research on how this might be done with an iterative > >solver. > >>> >John Swanson > >>> >Swanson Analysis Services, Inc.
> >>> >> -----Original Message----- > >>> >> From: Bohlen, Dan (GEAE) [SMTP:dan.bohlen@a...] > >>> >> Sent: Wednesday, March 06, 2002 11:33 AM > >>> >> To: 'xansys ' > >>> >> Subject: RE: [xansys] Regarding substructuring
> >>> >> I believe the short answer is: you can't.
> >>> >> Dear Users > >>> >> In substructuring , the generation pass has only frontal solver? How > >>> we > >>> >> can change the solver instead of frontal in generation pass.