Hello everyone,
I hope you can solve my problem. I need to calculate the volume change of a box subjected to pressure on all its internal faces. I have simply created a parallelepiped and modeled it with shell elements. I applied the pressure to all the internal faces of the box and solved it.
Is there a way to calculate the volume change of the box?
Thank you for you help and time.
Best regards,
Francesca
Student at Politecnico di Torino
Unless I am very wrong, I don’t think that there is a direct way to do it.
One possible way is to extract the locations of your nodes before and after
the loading is applied. Then you might need some surface numerical
integration to get the volume. Remember, the volume is the integral of a
varying area over length.
I hope this helps.
Best,
Mohammad
---====
Mohammad A Gharaibeh, Ph.D.
Associate Professor
Department of Mechanical Engineering
The Hashemite University
P.O. Box 330127
Zarqa, 13133, Jordan
Tel: +962 - 5 - 390 3333 Ext. 4771
Fax: +962 - 5 - 382 6348
---====
Hi Francesca.
You could try something like this (rough idea):
If you had to do it with a shell element box (still solid element surrounding), you would need to compensate for a half thickness due to the mid-surface shell.
The accuracy of all this would depend on the deformation of the box. If it is excessive compared to the surrounding solid elements, you may have some problems with convergence, collapsing solid elements etc.
Good luck.
Uffe Dal Eriksen
Ramboll Energy Transition,
Denmark
Classification: Confidential
-----Original Message-----
From: Francesca Pistorio via Xansys xansys-temp@list.xansys.org
Sent: 4. juli 2024 18:09
To: xansys-temp@list.xansys.org
Cc: Francesca Pistorio francesca.pistorio@polito.it
Subject: [Xansys] Volume variation computation
Hello everyone,
I hope you can solve my problem. I need to calculate the volume change of a box subjected to pressure on all its internal faces. I have simply created a parallelepiped and modeled it with shell elements. I applied the pressure to all the internal faces of the box and solved it.
Is there a way to calculate the volume change of the box?
Thank you for you help and time.
Best regards,
Francesca
Student at Politecnico di Torino
Xansys mailing list -- xansys-temp@list.xansys.org To unsubscribe send an email to xansys-temp-leave@list.xansys.org 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'm fairly sure newer versions of Workbench allow you to export deformed shape geometry. And you can export it to a new system to run a new analysis. In that case, the downstream system should report the volume of the deformed structures in the Geometry branch properties. But in your case with an open box, I think you would have to create an "soft" body (i.e., low modulus) inside the open box that follows the shape of the deformation. And you would have to dither on its volume in the downstream system.
-Matt
-----Original Message-----
From: Francesca Pistorio via Xansys xansys-temp@list.xansys.org
Sent: Thursday, July 4, 2024 12:09 PM
To: xansys-temp@list.xansys.org
Cc: Francesca Pistorio francesca.pistorio@polito.it
Subject: [Xansys] Volume variation computation
Hello everyone,
I hope you can solve my problem. I need to calculate the volume change of a box subjected to pressure on all its internal faces. I have simply created a parallelepiped and modeled it with shell elements. I applied the pressure to all the internal faces of the box and solved it.
Is there a way to calculate the volume change of the box?
Thank you for you help and time.
Best regards,
Francesca
Student at Politecnico di Torino
Xansys mailing list -- xansys-temp@list.xansys.org To unsubscribe send an email to xansys-temp-leave@list.xansys.org 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 Francesca, Hi Uffe,
I was about to suggest Uffe's way, except I would mesh internal volume instead of surrounding. This way the volume you are looking for is directly that of the deformed "air" volume, that you can get with ETABLE,volume,VOLU $ SSUM after a solve on deformed mesh using 0 pressure.
Best regards,
David Galindo
PHAREA ceo
-----Message d'origine-----
De : Uffe Dal Eriksen via Xansys xansys-temp@list.xansys.org
Envoyé : vendredi 5 juillet 2024 08:32
À : XANSYS Mailing List Home xansys-temp@list.xansys.org
Cc : Uffe Dal Eriksen UDE@ramboll.com
Objet : [Xansys] Re: Volume variation computation
Hi Francesca.
You could try something like this (rough idea):
If you had to do it with a shell element box (still solid element surrounding), you would need to compensate for a half thickness due to the mid-surface shell.
The accuracy of all this would depend on the deformation of the box. If it is excessive compared to the surrounding solid elements, you may have some problems with convergence, collapsing solid elements etc.
Good luck.
Uffe Dal Eriksen
Ramboll Energy Transition,
Denmark
Classification: Confidential
-----Original Message-----
From: Francesca Pistorio via Xansys xansys-temp@list.xansys.org
Sent: 4. juli 2024 18:09
To: xansys-temp@list.xansys.org
Cc: Francesca Pistorio francesca.pistorio@polito.it
Subject: [Xansys] Volume variation computation
Hello everyone,
I hope you can solve my problem. I need to calculate the volume change of a box subjected to pressure on all its internal faces. I have simply created a parallelepiped and modeled it with shell elements. I applied the pressure to all the internal faces of the box and solved it.
Is there a way to calculate the volume change of the box?
Thank you for you help and time.
Best regards,
Francesca
Student at Politecnico di Torino
Xansys mailing list -- xansys-temp@list.xansys.org To unsubscribe send an email to xansys-temp-leave@list.xansys.org 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.
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Hi all,
And if you are using ANSYS Workbench, there is a custom user defined result for VOLU.
If associated with solid elements, it represents each elements volume.
If associated with shell elements, it represents each elements area.
Regards,
Irene Slater
Corning Incorporated
-----Original Message-----
From: David GALINDO - Pharea via Xansys xansys-temp@list.xansys.org
Sent: Friday, July 5, 2024 4:48 AM
To: XANSYS Mailing List Home xansys-temp@list.xansys.org
Cc: Uffe Dal Eriksen UDE@ramboll.com; David GALINDO - Pharea d.galindo@pharea.com
Subject: [⚠️] [EXTERNAL]--[Xansys] Re: Volume variation computation
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Hi Francesca, Hi Uffe,
I was about to suggest Uffe's way, except I would mesh internal volume instead of surrounding. This way the volume you are looking for is directly that of the deformed "air" volume, that you can get with ETABLE,volume,VOLU $ SSUM after a solve on deformed mesh using 0 pressure.
Best regards,
David Galindo
PHAREA ceo
-----Message d'origine-----
De : Uffe Dal Eriksen via Xansys xansys-temp@list.xansys.org Envoyé : vendredi 5 juillet 2024 08:32 À : XANSYS Mailing List Home xansys-temp@list.xansys.org Cc : Uffe Dal Eriksen UDE@ramboll.com Objet : [Xansys] Re: Volume variation computation
Hi Francesca.
You could try something like this (rough idea):
If you had to do it with a shell element box (still solid element surrounding), you would need to compensate for a half thickness due to the mid-surface shell.
The accuracy of all this would depend on the deformation of the box. If it is excessive compared to the surrounding solid elements, you may have some problems with convergence, collapsing solid elements etc.
Good luck.
Uffe Dal Eriksen
Ramboll Energy Transition,
Denmark
Classification: Confidential
-----Original Message-----
From: Francesca Pistorio via Xansys xansys-temp@list.xansys.org
Sent: 4. juli 2024 18:09
To: xansys-temp@list.xansys.org
Cc: Francesca Pistorio francesca.pistorio@polito.it
Subject: [Xansys] Volume variation computation
Hello everyone,
I hope you can solve my problem. I need to calculate the volume change of a box subjected to pressure on all its internal faces. I have simply created a parallelepiped and modeled it with shell elements. I applied the pressure to all the internal faces of the box and solved it.
Is there a way to calculate the volume change of the box?
Thank you for you help and time.
Best regards,
Francesca
Student at Politecnico di Torino
Xansys mailing list -- xansys-temp@list.xansys.org To unsubscribe send an email to xansys-temp-leave@list.xansys.org 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 _______________________________________________
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Please send administrative requests such as deletion from XANSYS to xansys-mod@tynecomp.co.uk and not to the list
Well, a simple question to the ChatGPT provided a reasonable solution
(below). Please note that I didn't check the sanity of this.
To calculate the volume change of a box subjected to internal pressure
using ANSYS with shell elements, you can follow these steps:
Post-Processing Displacement Data:
Calculate New Node Positions:
Reconstruct the Deformed Shape:
Calculate the Deformed Volume:
Obtain Strain Data:
Calculate Volume Change:
Solve the Model:
Post-Processing:
Extract Displacement Data:
Extract Strain Data:
Volume Calculation:
If you are using ANSYS APDL, you can use the following steps:
Apply Pressure and Solve:
/prep7
! Define geometry, materials, and apply pressure
et,1,shell281
keyopt,1,8,1 ! Use full integration points
! Define geometry, meshing, boundary conditions, and loads
...
/solu
solve
finish
Post-Processing for Displacement:
/post1
set,last
*get,nnode,node,,count ! Number of nodes
*dim,disp,array,nnode,3 ! Create array to store displacements
*vget,disp(1,1),node,1,ux
*vget,disp(1,2),node,1,uy
*vget,disp(1,3),node,1,uz
*dim,newpos,array,nnode,3 ! Array for new positions
*do,i,1,nnode
*get,xpos,node,i,loc,x
*get,ypos,node,i,loc,y
*get,zpos,node,i,loc,z
newpos(i,1) = xpos + disp(i,1)
newpos(i,2) = ypos + disp(i,2)
newpos(i,3) = zpos + disp(i,3)
*enddo
! Export new positions for volume calculation
Post-Processing for Strain:
/post1
set,last
*get,nelem,elem,,count ! Number of elements
*dim,volstrain,array,nelem ! Array to store volumetric strain
*vget,volstrain(1),elem,1,eptemp ! Assuming vol strain is stored in
eptemp
*dim,elemvol,array,nelem ! Array to store element volumes
*vget,elemvol(1),elem,1,volu
*dim,totalvolstrain,array,1 ! Total volumetric strain
*voper,totalvolstrain(1),volstrain,elemvol,sum
*get,totvolsum,elem,0,volu,sum
totalvol = totalvolstrain/totvolsum ! Average volumetric strain
*stat,totalvol
4. **Calculate Deformed Volume**:
```apdl
V0 = initial_volume ! Define the initial volume of the box
Vd = V0 * (1 + totalvol) ! Deformed volume
*stat,Vd
By following these steps, you can calculate the volume change of the box
subjected to internal pressure using ANSYS. If you have specific initial
dimensions or additional details about the setup, those can be incorporated
into the calculations accordingly.
--
Mohammad
---====
Mohammad A Gharaibeh, Ph.D.
Associate Professor
Department of Mechanical Engineering
The Hashemite University
P.O. Box 330127
Zarqa, 13133, Jordan
Tel: +962 - 5 - 390 3333 Ext. 4771
Fax: +962 - 5 - 382 6348
---====
Hi Francesca ,
You could add a Commands (APDL) option and then use the *get command, to
obtain node displancement hence calculate the new volume.
Regards,
General Manager
COMPLX
"Ingeniería Avanzada para Soluciones Reales"
www.complx.com.mx [1]
Tel: 229 337 1365
Cel: 229 136 5599
El 2024-07-05 02:47, David GALINDO - Pharea via Xansys escribió:
Hi Francesca, Hi Uffe,
I was about to suggest Uffe's way, except I would mesh internal volume
instead of surrounding. This way the volume you are looking for is
directly that of the deformed "air" volume, that you can get with
ETABLE,volume,VOLU $ SSUM after a solve on deformed mesh using 0
pressure.
Best regards,
David Galindo
PHAREA ceo
-----Message d'origine-----
De : Uffe Dal Eriksen via Xansys xansys-temp@list.xansys.org
Envoyé : vendredi 5 juillet 2024 08:32
À : XANSYS Mailing List Home xansys-temp@list.xansys.org
Cc : Uffe Dal Eriksen UDE@ramboll.com
Objet : [Xansys] Re: Volume variation computation
Hi Francesca.
You could try something like this (rough idea):
If you had to do it with a shell element box (still solid element
surrounding), you would need to compensate for a half thickness due to
the mid-surface shell.
The accuracy of all this would depend on the deformation of the box. If
it is excessive compared to the surrounding solid elements, you may
have some problems with convergence, collapsing solid elements etc.
Good luck.
Uffe Dal Eriksen
Ramboll Energy Transition,
Denmark
Classification: Confidential
-----Original Message-----
From: Francesca Pistorio via Xansys xansys-temp@list.xansys.org
Sent: 4. juli 2024 18:09
To: xansys-temp@list.xansys.org
Cc: Francesca Pistorio francesca.pistorio@polito.it
Subject: [Xansys] Volume variation computation
Hello everyone,
I hope you can solve my problem. I need to calculate the volume change
of a box subjected to pressure on all its internal faces. I have simply
created a parallelepiped and modeled it with shell elements. I applied
the pressure to all the internal faces of the box and solved it.
Is there a way to calculate the volume change of the box?
Thank you for you help and time.
Best regards,
Francesca
Student at Politecnico di Torino
Xansys mailing list -- xansys-temp@list.xansys.org To unsubscribe send
an email to xansys-temp-leave@list.xansys.org 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 mailing list -- xansys-temp@list.xansys.org To unsubscribe send
an email to xansys-temp-leave@list.xansys.org 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.
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xansys-mod@tynecomp.co.uk and not to the list
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Hi,
In order to explicit the method I propose, here is the script for a 1x1x1 box meshed with shell181 and its internal volume with solid185.
Shell thickness is not considered in volume calculation since this is not an issue.
Last command returns the deformed volume in the output window.
Note that at the end of this script the undeformed model is lost. Files could be copied after 1st solve to keep model and results.
!*** modelling box and solving under internal pressure, not the interesting part so I use some $ for less lines
!*** Just note the model is a shell box which internal volume is meshed with near 0 stiffness 3D elements
fini $ /clear $ /prep7
block,0,1,0,1,0,1 $ esize,0.1
et,1,181 $ sectype,1,shell,,box $ secdata,0.01 $ mp,ex,1,200e9 $ mp,prxy,1,0.3
et,2,185 $ mp,ex,2,1 $ mp,prxy,2,0.3
type,1 $ secnum,1 $ mat,1 $ amesh,all
type,2 $ secnum,2 $ mat,2 $ vmesh,all
esel,s,ename,,181 $ sfe,all,1,pres,0,1e5 $ d,node(0,0,0),all,all,0
fini $ /solu $ allsel $ solve
!*****************************************************
!*** Start of the interesting part *******************
!*****************************************************
fini
/prep7
allsel
upgeom,1,last,last,file,rst ! update mesh to match the deformed shape obtained from applied pressure
fini
/solu
esel,s,ename,,181
sfe,all,1,pres,0,0 ! run a 2nd solve with 0 pressure
allsel
solve
fini
/post1
esel,s,ename,,185
etable,volume,volu ! sort volume of 3D elements
ssum
Best regards,
David Galindo
PHAREA ceo
De : Dr. Juan Pablo Toledo Gonzalez juan.toledo@complx.com.mx
Envoyé : vendredi 5 juillet 2024 22:42
À : XANSYS Mailing List Home xansys-temp@list.xansys.org
Cc : Uffe Dal Eriksen UDE@ramboll.com; David GALINDO - Pharea d.galindo@pharea.com
Objet : Re: [Xansys] Re: Volume variation computation
Hi Francesca ,
You could add a Commands (APDL) option and then use the *get command, to obtain node displancement hence calculate the new volume.
General Manager
COMPLX
"Ingeniería Avanzada para Soluciones Reales"
www.complx.com.mxhttp://www.complx.com.mx/
Tel: 229 337 1365
Cel: 229 136 5599
El 2024-07-05 02:47, David GALINDO - Pharea via Xansys escribió:
Hi Francesca, Hi Uffe,
I was about to suggest Uffe's way, except I would mesh internal volume instead of surrounding. This way the volume you are looking for is directly that of the deformed "air" volume, that you can get with ETABLE,volume,VOLU $ SSUM after a solve on deformed mesh using 0 pressure.
Best regards,
David Galindo
PHAREA ceo
-----Message d'origine-----
De : Uffe Dal Eriksen via Xansys <xansys-temp@list.xansys.orgmailto:xansys-temp@list.xansys.org>
Envoyé : vendredi 5 juillet 2024 08:32
À : XANSYS Mailing List Home <xansys-temp@list.xansys.orgmailto:xansys-temp@list.xansys.org>
Cc : Uffe Dal Eriksen <UDE@ramboll.commailto:UDE@ramboll.com>
Objet : [Xansys] Re: Volume variation computation
Hi Francesca.
You could try something like this (rough idea):
If you had to do it with a shell element box (still solid element surrounding), you would need to compensate for a half thickness due to the mid-surface shell.
The accuracy of all this would depend on the deformation of the box. If it is excessive compared to the surrounding solid elements, you may have some problems with convergence, collapsing solid elements etc.
Good luck.
Uffe Dal Eriksen
Ramboll Energy Transition,
Denmark
Classification: Confidential
-----Original Message-----
From: Francesca Pistorio via Xansys <xansys-temp@list.xansys.orgmailto:xansys-temp@list.xansys.org>
Sent: 4. juli 2024 18:09
To: xansys-temp@list.xansys.orgmailto:xansys-temp@list.xansys.org
Cc: Francesca Pistorio <francesca.pistorio@polito.itmailto:francesca.pistorio@polito.it>
Subject: [Xansys] Volume variation computation
Hello everyone,
I hope you can solve my problem. I need to calculate the volume change of a box subjected to pressure on all its internal faces. I have simply created a parallelepiped and modeled it with shell elements. I applied the pressure to all the internal faces of the box and solved it.
Is there a way to calculate the volume change of the box?
Thank you for you help and time.
Best regards,
Francesca
Student at Politecnico di Torino
Xansys mailing list -- xansys-temp@list.xansys.orgmailto:xansys-temp@list.xansys.org To unsubscribe send an email to xansys-temp-leave@list.xansys.orgmailto:xansys-temp-leave@list.xansys.org 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.ukmailto:xansys-mod@tynecomp.co.uk and not to the list _______________________________________________
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