High-order scheme and grid

 User Name Remember Me Password
 Register Blogs Members List Search Today's Posts Mark Forums Read

 LinkBack Thread Tools Display Modes
 September 14, 2000, 22:41 High-order scheme and grid #1 z.zeng Guest   Posts: n/a I am coding a Linear Stability Analysis for fluid dynamic problem, and therefore a genernalized eigenvale problem A x=lamda B x must be solved. The dimension of A and B is (4xNJxNK)^2.(NJ and NK is number of grid in y and z direction). Due to the limitaion of memory, NJxNK can only be up to 30x30, but it seems too coarse for my calcutation. My quesation is (1) If a higher-order difference scheme (e.g. 4-order)is adopted in stead of my present 2-order scheme, the problem caused by coarse grid can be remedied? (2) I remeber that a paper mentioned that a non-homgious grid would reduce the accurate of high-order scheme. I read it several years ago, and can not find it again now. What is your suggestion on a homgious or non-homgious grid? (3) Could you suggests a good high order difference scheme to me with corresponding literature? Your advises and suggestions on any above questions are highly appreciated. Thanks in advance. Zeng

 September 15, 2000, 18:05 Re: High-order scheme and grid #2 frederic felten Guest   Posts: n/a Hi, Check out the following publication: http://landau.mae.missouri.edu/~vasi...high-order.pdf Sincerely, Frederic Felten

 September 16, 2000, 06:48 Re: High-order scheme and grid #3 Chidu Guest   Posts: n/a Hi, It is a good idea to use a spectral type discretization if you are really limited by a coarse grid. This will give you much better results if your focus is to obtain very accurate eigenvalues. With finite-difference you can use arbitrarily higher-order approximations which is obviously limited by the number of grid points you have. There is a paper in the SIAM Journal which gives an algorithm to generate coefficients for arbitrary order of accuracy finite-difference scheme. The author escapes my memory, I will look it up and repost. chidu...

 September 17, 2000, 20:32 Re: High-order scheme and grid #4 Z.Zeng Guest   Posts: n/a Thanks you all for your kind help. Chidu mentioned paper seems very interesting, we wish you can find it. zeng

 September 18, 2000, 06:25 Re: High-order scheme and grid #5 K.S.Ravichandran Guest   Posts: n/a Chidu & Zeng You may look up Fornberg's paper "Generation of Finite-Difference Formulas on arbitrarily spaced grids", Math. Comp. V51, N0184, p699, 1988 Ravichandran

 September 18, 2000, 10:12 Re: High-order scheme and grid #6 Chidu Guest   Posts: n/a Exactly, Ravi. This is the paper. I was on vacation and did not have access to the info. Thanks. regards, chidu...

 October 14, 2000, 13:10 Re: High-order scheme and grid #7 ajay singh Guest   Posts: n/a please guide me for using higher order scheme for les

 Thread Tools Display Modes Linear Mode

 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 OffTrackbacks are On Pingbacks are On Refbacks are On Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post Freeman FLUENT 27 December 18, 2010 14:09 Dong Main CFD Forum 3 July 1, 2008 23:44 Chandra Shekhar Main CFD Forum 9 January 27, 2005 17:31 Sherry Clark CFX 4 October 20, 2004 23:27 Jafarnia Main CFD Forum 0 February 25, 2004 10:03

All times are GMT -4. The time now is 03:49.

 Contact Us - CFD Online - Top