Filter example

Question

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.

Answer 1

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.

Thanks

Chris