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Pankaj August 1, 2007 04:30

Initial value File Interpolation
 
Hi All!

When we specify initial value file and interpolate it onto definition file mesh,what it actually does?

Whether it just specifies the values of various dependent variables onto the boundaries or specifies them collectively (avg/min-max values)onto the domains?

If i do some changes in geometry and did another mesh for it,and specified previous result file(previous geom without changes) as initial value file and asked to iterpolate onto new mesh,to save computational time,whther it will predict diff results than the one which will start without any initial value file?

I think both(with and without initial value file)should give u same results if there is no change in physics,only the computational time differs.

pls comment.

Thanks and Regards,

Pankaj.


opaque August 1, 2007 07:32

Re: Initial value File Interpolation
 
Dear Pankaj,

1 - IVF into DFM: intersect the meshes and interpolate variable values to the new mesh vertex from element variable values at old mesh element vertices.

2 - Only interpolate mesh vertices values.

3 - As you said, you are using the interpolation as an initial guess. Therefore, the solution should be the same (see below)

4 - For a linear steady state calculation, the solution should be independent of the initial conditions (in any CFD code). For non-linear problems that is not always the case. For transient calculations, the solution is very much dependent of the initial conditions (in any CFD code)

Hope this helps,

Opaque


Pankaj August 3, 2007 04:44

Re: Initial value File Interpolation
 
Thanks Opaque,

" For a linear steady state calculation, the solution should be independent of the initial conditions (in any CFD code)."

I was waiting for this confirmation only.

Regards, Pankaj.


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