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Kyung-Seok, Kim July 14, 2004 08:06

3D Interpolation
 
Hi! everybody. Now, I'm studying on 3D Multi-block method. But while I study above,I have some trouble. I hope you can help me.

Here is my problem.

There is 3D multi-block which consist of 2 block. and 'The bottom interface of upper block'(let's say B1) and 'the top interface of lower block'(B2) are NOT matched !

and I use FDM scheme,so I want to transfer potential information at grid point from B1 to B2.

and Now I try to use interpolation method.

Summarizing above thing, non-maching multi-block interface treatment of using FDM.

Q1)Is it right that I use interpolation like above problem?

Q2-1)If right,please recommend good reference,book and something like stuff.

Q2-2)If wrong,What am I gonna do ? ^^;

Thank you in advance.

I am waiting for your reply,Pro!

Halim Choi July 14, 2004 22:46

Re: 3D Interpolation
 
Read following two papers given in the same journal issue : Numerical Heat Transfer: Fundamentals, Volume 32, Issue 4, December 1997

1.Computation of Unsteady Flows Using Non-Matching Blocks of Structured Grid by Lilek et al.

2. An Implicit Finite-Volume Method Using Non-Matching Blocks of Structured Grid by Lilek et al.

I had the papers, but I can not find them now. Thus I canot give you the detailed informations. I hope this helps you.

Good Luck


Lipo Wang August 17, 2004 09:03

extreme points problem
 
Hello,everyone My problem is as follows: I have got the value of scalar at every grid point of a 256 cube and also have found these extreme points in this scalar field with a criteria of [S(i)-S(i+1)]*[Si-S(i-1)]>0, i should be in three directions: x, y and z. But we want more precise positions of these points, so interpolation is needed.

I tried to do interpolation and found some extreme points will dispear with the same criteria. This is due to the effect from no-adjencent points. For example, S(0,0,0) is extreme, then S(1,1,0), S(1,1,1),S(1,-1,0) are no-adjencent. So I wonder for interpolation, should I also consider these no-adjencent points, or only adjent points(totally they are S(0,0,1),S(0,0,-1),S(1,0,0),S(-1,0,0),S(0,1,0),S(0,-1,0))? Of course, more points considered, more reasonable. But more negative effect will destroy the criteria. How do you think about it?

Great thanks



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