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

Transient adaptation

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   October 17, 2005, 10:19
Default Transient adaptation
  #1
ganesh
Guest
 
Posts: n/a
Dear Friends,

I am working on transient adaptation and presently faced with a problem. I have considered a standard 2-D Riemann problem ( 4 states in the 4 quadrants ) and try to solve it starting from an initial coarse grid. For the present problem where the simulation time is 0.3s, I have perfomed an adaptation in every 10 steps. I have used 100 steps in total with a physical time step of 0.003s. The problem is solved using a cell-centered finite volume scheme on a cartesian grid with limiting and linear reconstruction using Roe scheme and Dual time stepping.

The trouble is the final solution is not quite in match with the results on a fine mesh, which means there is some trouble in solution advancement. I understand that it is critical that the conservation be preserved when we advance in time. Thus when we transfer the solution from a coarse mesh to a finer mesh, this has to be taken care of. I have tried the following options

1. The values in the coarser cell is directly supplied as such to its children. 2. The values in the coarser cell are supplied to children by using a linear interpolation. ( Ham,Lien and Strong, JCP 2002)

However, in both cases I still do not manage to get the right solution. I am not clear if my solution transfer procedure is right, but I understand the first one is not quite right.

Could you please give your suggestions or references to this problem

Thanks in advance,

Ganesh

  Reply With Quote

Reply


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
Transient conduction possible in fluent? jlefevre76 FLUENT 2 February 5, 2013 10:53
Laminar gas flow under slight suction - transient works but not steady audrey CFX 1 September 8, 2011 20:43
Best practice for transient simulations? siw CFX 5 October 30, 2010 06:45
transient simulation of a rotating rectangle icesniffer CFX 1 August 8, 2009 08:25
difference between false and true transient mahesh prakash Main CFD Forum 1 January 21, 1999 14:45


All times are GMT -4. The time now is 14:20.