Peter,

I am not sure about oscillation. However, coarse discretization,
especially in the vertical, definitely causes numerical dispersion
in FEFLOW - at times, involving large errors.

Cheers,

Shlomo Orr.



----- Original Message -----
From: peter.schaetzl
To: feflow@...
Sent: Wednesday, November 26, 2008 1:47 AM
Subject: [feflow] Re: too much dispersion within an unsaturated flow and mass
transport model


Monica,

A too coarse discretization would typically lead to oscillations
rather than high numerical dispersion. So please check whether your
dispersivity values are realistic and whether you have turned on an
upwind method (in Temporal&Control data). Upwind methods stabilize the
solution on too coarse meshes, but depending on the method used a high
amount of artificial dispersion might be added.

Hope this helps

Peter
FEFLOW Support Team