CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > OpenFOAM Programming & Development

Stress equations

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Display Modes
Old   September 8, 2015, 08:07
Default Stress equations
  #1
Senior Member
 
Tobi's Avatar
 
Tobias Holzmann
Join Date: Oct 2010
Location: Leoben (Austria)
Posts: 1,566
Blog Entries: 6
Rep Power: 27
Tobi will become famous soon enoughTobi will become famous soon enough
Send a message via ICQ to Tobi Send a message via Skype™ to Tobi
Dear all,

does anybody have references to the equations used in the stress solvers?
Thanks in advance,
__________________
Best regards,
Tobias Holzmann

Some interesting OpenFOAM tutorials, publications and videos on www.Holzmann-cfd.de
OpenFOAM Beginners should check out the new wiki on wiki.openfoam.com
A list of some active OpenFOAM contributers can be found »here«
A book about the basics of »Mathematics, Numerics, Derivations and OpenFOAM« can be found on www.Holzmann-cfd.de
Tobi is offline   Reply With Quote

Old   September 13, 2015, 12:37
Default
  #2
Member
 
Jon Elvar Wallevik
Join Date: Nov 2010
Location: Reykjavik, ICELAND
Posts: 78
Rep Power: 12
JonW will become famous soon enough
Hi T.
Are you thinking about the sigmaEq = sqrt((3.0/2.0)*magSqr(dev(sigma))) in calculateStress.H ??
I have been thinking about the same thing. The best I have come up with is what is written in the book by Mase (Schaum's Outline of Continuum Mechanics by George Mase). See Equation (8.24), page 182. But that chapter is about "strain hardening rules" (increase in material strength by strain) which I dont think is relevant in the solidDisplacementFoam (Lamé constants of elasticity are constants here, i.e. not dependent on stress). So it would be nice to have another reference to the application of equivalent stress, in which constant elasticity is assumed. I have also just added von Mises (i.e. sqrt(S:S/2)) in to this part and used that. But I dont know how correct that is since I am not a specialist in solid mechanics.

Hope this helps

cheers
J.
JonW is offline   Reply With Quote

Old   September 14, 2015, 07:29
Default
  #3
Senior Member
 
Tobi's Avatar
 
Tobias Holzmann
Join Date: Oct 2010
Location: Leoben (Austria)
Posts: 1,566
Blog Entries: 6
Rep Power: 27
Tobi will become famous soon enoughTobi will become famous soon enough
Send a message via ICQ to Tobi Send a message via Skype™ to Tobi
Hi, your eqn is correct. Search for elastic Stress and Wikipedia. There are good references.

Kind regards
Tobi
__________________
Best regards,
Tobias Holzmann

Some interesting OpenFOAM tutorials, publications and videos on www.Holzmann-cfd.de
OpenFOAM Beginners should check out the new wiki on wiki.openfoam.com
A list of some active OpenFOAM contributers can be found »here«
A book about the basics of »Mathematics, Numerics, Derivations and OpenFOAM« can be found on www.Holzmann-cfd.de
Tobi is offline   Reply With Quote

Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
[ANSYS Meshing] Error in Workbench "Unable to attach to geometry file" Jeremie84 ANSYS Meshing & Geometry 67 February 24, 2016 07:55
UDS or UDF for modify shear stress equations..? aeroprince1986 Fluent UDF and Scheme Programming 0 April 14, 2015 04:16
Turbulence: Reynolds stress equations kharicha FLUENT 0 March 16, 2006 09:50
Turbulence: Reynolds stress equations kharicha Main CFD Forum 0 March 16, 2006 09:48
shear stress scalar definitions? Novak Elliott CFX 0 April 6, 2003 01:45


All times are GMT -4. The time now is 09:15.