CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > General Forums > Main CFD Forum

Mixing traction/pseudo-traction boundary conditions in incompressible flow

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   January 10, 2014, 10:21
Default Mixing traction/pseudo-traction boundary conditions in incompressible flow
  #1
New Member
 
Join Date: May 2009
Posts: 28
Rep Power: 16
walli is on a distinguished road
I was wondering if there is a way to incorporate the traction boundary conditions in discretizations using the pseudo-traction form of the Stokes problem or vice versa. Is there some literature on this or does one simply have no chance? I am mainly interested in finite-elements, but pointers to work dealing with other discretizations or publications dealing with both types of boundary conditions within one simulation would also be helpful.

Stress form of Stokes with pseudo-traction b.c.:

-\nabla\cdot(\nu(\nabla \mathbf{u} + (\nabla \mathbf{u})^T) - p I) = \mathbf{f},  \quad \text{and} \quad  \nabla\cdot \mathbf{u} = 0 \quad \text{in} \quad \Omega

\mathbf{u} = 0 \quad \text{on} \quad \partial\Omega\backslash\Gamma,  \quad \text{and} \quad (\nu\nabla \mathbf{u} - p I)\cdot\mathbf{n} = \mathbf{t}\quad \text{on} \quad \Gamma

Pseudo-stress form of Stokes with traction b.c.:

-\nu\Delta\mathbf{u} + \nabla p = \mathbf{f},  \quad \text{and} \quad  \nabla\cdot \mathbf{u} = 0 \quad \text{in} \quad \Omega

\mathbf{u} = 0 \quad \text{on} \quad \partial\Omega\backslash\Gamma,  \quad \text{and} \quad (\nu(\nabla \mathbf{u} + (\nabla \mathbf{u})^T) - p I)\cdot\mathbf{n} = \mathbf{t}\quad \text{on} \quad \Gamma

I am aware that these boundary conditions are not natural in the respective (weak) formulations, but out of curiosity I would like to know if there are approaches to incorporate these boundary conditions anyway in a stable and convergent manner.
walli is offline   Reply With Quote

Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
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 Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Wind turbine simulation Saturn CFX 58 July 3, 2020 01:13
Domain Imbalance HMR CFX 5 October 10, 2016 05:57
Implementation of boundary conditions for FVM Tom Main CFD Forum 7 August 26, 2014 05:58
Please help with flow around car modelling! Tudor Miron CFX 17 March 19, 2004 19:23
Boundary conditions? Tom Main CFD Forum 0 November 5, 2002 01:54


All times are GMT -4. The time now is 14:44.