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

LDG viscous flux discretization procedure

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

Reply
 
LinkBack Thread Tools Display Modes
Old   July 12, 2010, 11:36
Default LDG viscous flux discretization procedure
  #1
New Member
 
sonali
Join Date: Jul 2010
Posts: 3
Rep Power: 8
aerosonali is on a distinguished road
Can anyone comment on the efficacy of LDG viscous flux schemes for high order methods like DG, spectral volume or the spectral difference methods. I have read about it and it looks very simple and elegant in contrast to other formulations like the penalty formulation etc. However, has anyone experienced any undesirable features (due to its lack of symmetry) , while using LDG?

Sonali
aerosonali is offline   Reply With Quote

Old   July 13, 2010, 11:40
Default some discussions on LDG
  #2
New Member
 
yughi
Join Date: Jul 2010
Posts: 1
Rep Power: 0
sunyughi is on a distinguished road
Hi Sonali,
well, LDG is great with respect to its simplicity, easy to use approach and lack of a length scale (which is really something worth mentioning for heavily skewed and non-uniform grids). Thus it has been used in several areas of engineering (not just confined to aerodynamics) [2].

However it has been shown by Kannan and Wang [1] to be very dissipative, when compared to the penalty and the BR2 formulations. This paper, describes the process using a very clean eigen value analysis.

Very recently Kannan and Wang[3] came up with a variant of LDG : called LDG2. This is more symmetrical than LDG, but still has the advantages of LDG( like simplicity, lack of a length scale etc). This was shown to have more accuracy than the LDG.

1. R. Kannan and Z.J. Wang, “A study of viscous flux formulations for a p-multigrid spectral volume Navier stokes solver”, Journal of Scientific Computing, Volume 41, Number 2, November, 2009.
2. R. Kannan, “An Implicit LU-SGS Spectral Volume Method for the Moment Models in Device Simulations: Formulation in 1D and application to a p-multigrid algorithm”, International Journal for Numerical Methods in Biomedical Engineering (formerly Communications in numerical methods in engineering), accepted on October 11, 2009, Published Online: 1 Feb 2010.
3. Kannan R. and Wang., "LDG2: A Variant of the LDG Flux Formulation for the Spectral Volume Method", Journal of Scientific Computing, Received: 28 April 2009 Revised: 27 May 2010 Accepted: 31 May 2010 Published online: 20 June 2010

Hope this helps
Yughi
sunyughi is offline   Reply With Quote

Old   July 13, 2010, 12:22
Default
  #3
New Member
 
sonali
Join Date: Jul 2010
Posts: 3
Rep Power: 8
aerosonali is on a distinguished road
That was am informative post Yughi.
Thanks
Sonali
aerosonali 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
Viscous Flux Jacobian bearcat Main CFD Forum 10 March 11, 2010 18:14
viscous flux treatment in compressible NS sovler JG Main CFD Forum 2 January 9, 2008 16:29
Jacobian Coefficient matrices for the viscous flux Andy Main CFD Forum 8 February 26, 2004 00:53
Jacobian Coefficient matrices for the viscous flux Andy Main CFD Forum 0 February 19, 2004 14:59
Replace periodic by inlet-outlet pair lego CFX 3 November 5, 2002 21:09


All times are GMT -4. The time now is 06:58.