Hi, I have submitted a report to my local ANSYS support office; they had never seen it either, but would forward it to ANSYS. I will let you know when they get back to me, and check the model for over constraints that I might have missed. Best regards, Björn Fallqvist PhD, Solid Mechanics Lightness by Design AB Stadsgården 10, 116 45 Stockholm +46729261384 bjorn.fallqvist@lightness.eu bfa@kth.se ________________________________________ Från: Matthew Pausley <mpausley@nuvotronics.com> Skickat: den 22 augusti 2018 14:03 Till: XANSYS Mailing List Temporary Home Ämne: Re: [Xansys] ANSYS Mechanical error: "The nodal connectivity of contact element has changed". If Tom's suggestion to check for overlapping constraints reveals something, there are some tricks to deal with that using nodal named selections I can offer. Matthew Pausley | Mechanical Analyst | Nuvotronics, Inc 2305 Presidential Drive | Durham, NC 27703 | mpausley@nuvotronics.com www.nuvotronics.com This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error, please notify the sender immediately of that fact by return e-mail and permanently delete the e-mail and any attachments. -----Original Message----- From: Tom <cameljoe@optonline.net> Sent: Wednesday, August 22, 2018 7:46 AM To: XANSYS Mailing List Temporary Home <xansys-temp@xansystest.info> Subject: Re: [Xansys] ANSYS Mechanical error: "The nodal connectivity of contact element has changed". I myself have never seen that message. Typically, when mic over constraint occurs, it’s because the same geometry, e.g., an edge or vertex or face, is scoped to more than one condition, such as mpc contact, remote bc, bc, etc... I have many times seen the over-constraint warning in my models, and then dug back in to eliminate them, but I have never seen the error you’re describing. Have you submitted a support request to your local ASD? Perhaps a better understanding of what the warning message means would benefit us all. Best regards, Tom Caltabellotta LGS Innovations Sent from my iPhone > On Aug 22, 2018, at 7:59 AM, Björn Fallqvist <bfa@kth.se> wrote: > > Dear Tom, > > I know, but I am typically experiencing convergence issues if I do not set the formulation to MPC when I have significant gaps (joints are not an option with this particular geometry). I did try to change the formulation to "Pure penalty", and then "Program controlled", but the original error message persists. Quite strange. > > Thanks, > Björn Fallqvist > > PhD, Solid Mechanics > Lightness by Design AB > Stadsgården 10, 116 45 > Stockholm > +46729261384 > > bjorn.fallqvist@lightness.eu > bfa@kth.se > > ________________________________________ > Från: Tom <cameljoe@optonline.net> > Skickat: den 22 augusti 2018 12:38 > Till: XANSYS Mailing List Temporary Home > Ämne: Re: [Xansys] ANSYS Mechanical error: "The nodal connectivity of contact element has changed". > > If you have significant gaps, try increasing the pinball region, or consider the use of joints instead. > > Best regards, > Tom Caltabellotta > LGS Innovations > > Sent from my iPhone > >> On Aug 22, 2018, at 1:46 AM, Björn Fallqvist <bfa@kth.se> wrote: >> >> Dear Harish, >> >> I will try it, and see what happens, although I have a feeling other issues will occur (there are significant gaps in the model, and I usually have more luck with the MPC-formulation than others). >> >> Best regards, >> Björn Fallqvist >> >> PhD, Solid Mechanics >> Lightness by Design AB >> Stadsgården 10, 116 45 >> Stockholm >> +46729261384 >> >> bjorn.fallqvist@lightness.eu >> bfa@kth.se >> >> ________________________________________ >> Från: Harish Radhakrishnan <harish.radhakrishnan@ansys.com> >> Skickat: den 21 augusti 2018 15:44 >> Till: XANSYS Mailing List Temporary Home >> Ämne: Re: [Xansys] ANSYS Mechanical error: "The nodal connectivity of contact element has changed". >> >> Hello Bjorn, >> >> I believe this error may be due to over constraint issues with overlapping >> MPC contacts. Can you see if this issue persists if you change those MPC >> contacts to Program Controlled option? >> >> Harish >> >> Harish Radhakrishnan >> Product Manager - Mechanical Products >> ANSYS Inc >> 15915 Katy Freeway, Suite 550 >> Houston, TX 77094 >> Office: 281-676-7013 >> >> >> >> >>> On Tue, Aug 21, 2018 at 6:06 AM, Björn Fallqvist <bfa@kth.se> wrote: >>> >>> Dear XANSYS users, >>> >>> >>> I am running a static structural analysis at the moment, and while the >>> solution converges, I see a recurring warning message that bugs me: >>> >>> >>> "WARNING: The nodal connectivity of contact element xxxxxx has changed >>> during assembly loop (from target node xxxxxx to xxxxxx). This should not >>> happen." (xxxxxx element numbers). Has anyone seen this particular warning >>> message before, or know the cause of it? Could it be that a particular >>> contact is displaced in such a way as to move outside the pinball radius, >>> or something similar? >>> >>> ? >>> >>> It is a fairly straightforward model including: >>> >>> A large number of bonded contacts (mix of MPC and Program-controlled >>> formulations) >>> >>> One set of frictional edge-face contacts >>> >>> Large displacement effects turned on >>> >>> Bi-linear isotropic plastic material behaviour >>> >>> A compression-only support >>> >>> >>> Best regards, >>> >>> Björn Fallqvist >>> >>> PhD, Solid Mechanics >>> Lightness by Design AB >>> Stadsgården 10, 116 45 >>> Stockholm >>> _______________________________________________ >>> Xansys-temp mailing list >>> Xansys-temp@xansystest.info >>> http://xansystest.info/mailman/listinfo/xansys-temp_xansystest.info >>> If you are receiving too many emails from XANSYS please consider changing >>> account settings to Digest mode which will send a single email per day. >>> >>> Please send administrative requests such as deletion from XANSYS to >>> xansys-mod@tynecomp.co.uk and not to the list >>> >> _______________________________________________ >> Xansys-temp mailing list >> Xansys-temp@xansystest.info >> http://xansystest.info/mailman/listinfo/xansys-temp_xansystest.info >> If you are receiving too many emails from XANSYS please consider changing account settings to Digest mode which will send a single email per day. >> >> Please send administrative requests such as deletion from XANSYS to xansys-mod@tynecomp.co.uk and not to the list >> >> _______________________________________________ >> Xansys-temp mailing list >> Xansys-temp@xansystest.info >> http://xansystest.info/mailman/listinfo/xansys-temp_xansystest.info >> If you are receiving too many emails from XANSYS please consider changing account settings to Digest mode which will send a single email per day. >> >> Please send administrative requests such as deletion from XANSYS to xansys-mod@tynecomp.co.uk and not to the list > > > _______________________________________________ > Xansys-temp mailing list > Xansys-temp@xansystest.info > http://xansystest.info/mailman/listinfo/xansys-temp_xansystest.info > If you are receiving too many emails from XANSYS please consider changing account settings to Digest mode which will send a single email per day. > > Please send administrative requests such as deletion from XANSYS to xansys-mod@tynecomp.co.uk and not to the list > > _______________________________________________ > Xansys-temp mailing list > Xansys-temp@xansystest.info > http://xansystest.info/mailman/listinfo/xansys-temp_xansystest.info > If you are receiving too many emails from XANSYS please consider changing account settings to Digest mode which will send a single email per day. > > Please send administrative requests such as deletion from XANSYS to xansys-mod@tynecomp.co.uk and not to the list _______________________________________________ Xansys-temp mailing list Xansys-temp@xansystest.info http://xansystest.info/mailman/listinfo/xansys-temp_xansystest.info If you are receiving too many emails from XANSYS please consider changing account settings to Digest mode which will send a single email per day. Please send administrative requests such as deletion from XANSYS to xansys-mod@tynecomp.co.uk and not to the list This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error, please notify the sender immediately of that fact by return e-mail and permanently delete the e-mail and any attachments. _______________________________________________ Xansys-temp mailing list Xansys-temp@xansystest.info http://xansystest.info/mailman/listinfo/xansys-temp_xansystest.info If you are receiving too many emails from XANSYS please consider changing account settings to Digest mode which will send a single email per day. Please send administrative requests such as deletion from XANSYS to xansys-mod@tynecomp.co.uk and not to the list