Empathy List Archives

BF

Björn Fallqvist

Tue, Aug 21, 2018 11:06 AM

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

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

HR

Harish Radhakrishnan

Tue, Aug 21, 2018 1:44 PM

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

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 >

BF

Björn Fallqvist

Wed, Aug 22, 2018 4:46 AM

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

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

T

Tom

Wed, Aug 22, 2018 10:38 AM

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

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

BF

Björn Fallqvist

Wed, Aug 22, 2018 10:59 AM

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

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

MN

MISIARA Nicolas

Wed, Aug 22, 2018 11:30 AM

Hi Björn,
Do you resort to remeshing ?
Additionally, I personally refer to this particular ANSYS Tutorial for WB when I got contact concerns :
http://inside.mines.edu/~apetrell/ENME442/Labs/1301_ENME442_lab6_lecture.pdf
Best regards

Nicolas Misiara
Research engineer
CEA Saclay

-----Message d'origine-----
De : Björn Fallqvist [mailto:bfa@kth.se]
Envoyé : mercredi 22 août 2018 13:00
À : XANSYS Mailing List Temporary Home xansys-temp@xansystest.info
Objet : Re: [Xansys] ANSYS Mechanical error: "The nodal connectivity of contact element has changed".

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

Hi Björn, Do you resort to remeshing ? Additionally, I personally refer to this particular ANSYS Tutorial for WB when I got contact concerns : http://inside.mines.edu/~apetrell/ENME442/Labs/1301_ENME442_lab6_lecture.pdf Best regards Nicolas Misiara Research engineer CEA Saclay -----Message d'origine----- De : Björn Fallqvist [mailto:bfa@kth.se] Envoyé : mercredi 22 août 2018 13:00 À : XANSYS Mailing List Temporary Home <xansys-temp@xansystest.info> Objet : Re: [Xansys] ANSYS Mechanical error: "The nodal connectivity of contact element has changed". 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

BF

Björn Fallqvist

Wed, Aug 22, 2018 11:37 AM

Hi, Nicola

Do you mean adaptive regions? No, I do not (not included in our license). Thanks for the link.

Björn Fallqvist

PhD, Solid Mechanics
Lightness by Design AB
Stadsgården 10, 116 45
Stockholm
+46729261384

bjorn.fallqvist@lightness.eu
bfa@kth.se

Från: MISIARA Nicolas nicolas.misiara@cea.fr
Skickat: den 22 augusti 2018 13:30
Till: XANSYS Mailing List Temporary Home
Ämne: Re: [Xansys] ANSYS Mechanical error: "The nodal connectivity of contact element has changed".

Hi Björn,
Do you resort to remeshing ?
Additionally, I personally refer to this particular ANSYS Tutorial for WB when I got contact concerns :
http://inside.mines.edu/~apetrell/ENME442/Labs/1301_ENME442_lab6_lecture.pdf
Best regards

Nicolas Misiara
Research engineer
CEA Saclay

-----Message d'origine-----
De : Björn Fallqvist [mailto:bfa@kth.se]
Envoyé : mercredi 22 août 2018 13:00
À : XANSYS Mailing List Temporary Home xansys-temp@xansystest.info
Objet : Re: [Xansys] ANSYS Mechanical error: "The nodal connectivity of contact element has changed".

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

Hi, Nicola Do you mean adaptive regions? No, I do not (not included in our license). Thanks for the link. Björn Fallqvist PhD, Solid Mechanics Lightness by Design AB Stadsgården 10, 116 45 Stockholm +46729261384 bjorn.fallqvist@lightness.eu bfa@kth.se ________________________________________ Från: MISIARA Nicolas <nicolas.misiara@cea.fr> Skickat: den 22 augusti 2018 13:30 Till: XANSYS Mailing List Temporary Home Ämne: Re: [Xansys] ANSYS Mechanical error: "The nodal connectivity of contact element has changed". Hi Björn, Do you resort to remeshing ? Additionally, I personally refer to this particular ANSYS Tutorial for WB when I got contact concerns : http://inside.mines.edu/~apetrell/ENME442/Labs/1301_ENME442_lab6_lecture.pdf Best regards Nicolas Misiara Research engineer CEA Saclay -----Message d'origine----- De : Björn Fallqvist [mailto:bfa@kth.se] Envoyé : mercredi 22 août 2018 13:00 À : XANSYS Mailing List Temporary Home <xansys-temp@xansystest.info> Objet : Re: [Xansys] ANSYS Mechanical error: "The nodal connectivity of contact element has changed". 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

MN

MISIARA Nicolas

Wed, Aug 22, 2018 11:45 AM

Björn,
Exactly, sorry for using the wrong designation.
I was wondering if ANSYS could have been bothered by changes in nodal connectivity, especially due to remeshing.
Now that's obviously not the case :)
Hope you'll find a satisfactory explanation.
Best regards

Nicolas Misiara
Research engineer
CEA Saclay

-----Message d'origine-----
De : Björn Fallqvist [mailto:bfa@kth.se]
Envoyé : mercredi 22 août 2018 13:38
À : XANSYS Mailing List Temporary Home xansys-temp@xansystest.info
Objet : Re: [Xansys] ANSYS Mechanical error: "The nodal connectivity of contact element has changed".

Hi, Nicola

Do you mean adaptive regions? No, I do not (not included in our license). Thanks for the link.

Björn Fallqvist

PhD, Solid Mechanics
Lightness by Design AB
Stadsgården 10, 116 45
Stockholm
+46729261384

bjorn.fallqvist@lightness.eu
bfa@kth.se

Från: MISIARA Nicolas nicolas.misiara@cea.fr
Skickat: den 22 augusti 2018 13:30
Till: XANSYS Mailing List Temporary Home
Ämne: Re: [Xansys] ANSYS Mechanical error: "The nodal connectivity of contact element has changed".

Hi Björn,
Do you resort to remeshing ?
Additionally, I personally refer to this particular ANSYS Tutorial for WB when I got contact concerns :
http://inside.mines.edu/~apetrell/ENME442/Labs/1301_ENME442_lab6_lecture.pdf
Best regards

Nicolas Misiara
Research engineer
CEA Saclay

-----Message d'origine-----
De : Björn Fallqvist [mailto:bfa@kth.se] Envoyé : mercredi 22 août 2018 13:00 À : XANSYS Mailing List Temporary Home xansys-temp@xansystest.info Objet : Re: [Xansys] ANSYS Mechanical error: "The nodal connectivity of contact element has changed".

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

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

Björn, Exactly, sorry for using the wrong designation. I was wondering if ANSYS could have been bothered by changes in nodal connectivity, especially due to remeshing. Now that's obviously not the case :) Hope you'll find a satisfactory explanation. Best regards Nicolas Misiara Research engineer CEA Saclay -----Message d'origine----- De : Björn Fallqvist [mailto:bfa@kth.se] Envoyé : mercredi 22 août 2018 13:38 À : XANSYS Mailing List Temporary Home <xansys-temp@xansystest.info> Objet : Re: [Xansys] ANSYS Mechanical error: "The nodal connectivity of contact element has changed". Hi, Nicola Do you mean adaptive regions? No, I do not (not included in our license). Thanks for the link. Björn Fallqvist PhD, Solid Mechanics Lightness by Design AB Stadsgården 10, 116 45 Stockholm +46729261384 bjorn.fallqvist@lightness.eu bfa@kth.se ________________________________________ Från: MISIARA Nicolas <nicolas.misiara@cea.fr> Skickat: den 22 augusti 2018 13:30 Till: XANSYS Mailing List Temporary Home Ämne: Re: [Xansys] ANSYS Mechanical error: "The nodal connectivity of contact element has changed". Hi Björn, Do you resort to remeshing ? Additionally, I personally refer to this particular ANSYS Tutorial for WB when I got contact concerns : http://inside.mines.edu/~apetrell/ENME442/Labs/1301_ENME442_lab6_lecture.pdf Best regards Nicolas Misiara Research engineer CEA Saclay -----Message d'origine----- De : Björn Fallqvist [mailto:bfa@kth.se] Envoyé : mercredi 22 août 2018 13:00 À : XANSYS Mailing List Temporary Home <xansys-temp@xansystest.info> Objet : Re: [Xansys] ANSYS Mechanical error: "The nodal connectivity of contact element has changed". 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 _______________________________________________ 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

T

Tom

Wed, Aug 22, 2018 11:46 AM

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

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

MP

Matthew Pausley

Wed, Aug 22, 2018 12:03 PM

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.

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@list.xansys.org

ANSYS Mechanical error: "The nodal connectivity of contact element has changed".