Filter example

0 votes
asked May 9, 2017 in AEM3D by [email protected] (170 points)
Hi moderators

I am trying to use the filter option with the aim to avoid numerical diffusion. However, I have not got any results so far. Do you have a simple example (it does not matter the values) using temperature filter? could you share?

so far I am just trying to run the model, no with real values.

I am doing this :

  1                                                        IFILTER                 

  0.2                                                     FILTER_WTR_TEMP

  1e-9                                                   filter_bPE_threshold
  1e-7                                                   filter_mass_threshold

Is the above correct?. It is not clear to me the meaning of (below lines):

IFILTER Filter control
1 = off (default)
2 = constant filter or filter form filter files
2 = background potential energy filter - salinity
3 = background potential energy filter - temperature

Should I use 3?

Please, any guidance.

Thank you in advance.

Ricardo R.B.

1 Answer

0 votes
answered May 12, 2017 by dallimor (6,200 points)
Hi Ricardo,

What you have is correct if you want to have a constant filter coefficient of 0.2 for temperature.  

The background potential energy methods attempt to dynamically set the filter based on PE changes during the scalar advection routines.  However these can't be run with inflows or outflows.


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