Settings for a "well-behaved" simulation

[gioviciconte]

Hello, first of all thank you fo this amazing software.
I have a question regarding the settings for a real-world downscaled simulation. I started from your tutorial, but I’m having trouble obtaining a "well-behaved" simulation. In the figure below, I show a slice of the domain (three velocity components and the pressure) after 20 seconds of physical time. As you can see, there are many waves propagating through the domain, and the situation does not improve over time.

I played with the grid properties (size, number of points, deformation) but haven’t had much success. I also tried adjusting the advection scheme, with similar results. Do you have any advice on what might be going wrong or where I should look next?
Attached the input file. LES_input.txt
Thank you

[jprestop]

Hi @gioviciconte. Thanks for reaching out and for your interest in using FastEddy. We noticed you recently marked your discussion as outdated. It sounds like you were able to resolve the issue with your simulation setup. If everything’s working now, that’s great to hear! Could you please provide us with some information on what the problem was and how you solved it? If you’re still running into difficulties or have any remaining questions, we’d be happy to take another look.

[gioviciconte]

Hi, thanks for the answer! I thought the wave-like pattern I saw was due to bad numerical settings, but it turns out it was my mistake. There was an issue when converting the data from GIS—mainly some incorrectly defined lat/lon values—which caused a mismatch between the IC and BC in the NetCDF files used by the Python scripts. I wanted to delete the question once I figured it out, but it was not possible, so I marked it outdated.

[jprestop]

Thank you @gioviciconte for the for the follow up and clarification. We were just recently made aware of a similar experience from a new NCAR user. In creating the georeference input netCDF file for the GeoSpec step of the coupling procedure, this user noted that some GIS tools write arrays beginning from the northwest element rather than from the southwest element (as the coupling workflow expects). It is necessary to ensure the georeference input NetCDF file arrays begin from the southwest by flipping if necessary the original GIS provided-arrays in the north-south dimension before writing out the georeference input NetCDF file required for the GeoSpec step. A note will be added to the documentation of the downscaling procedure to provide clarification of this requirement. Thank you again for providing the valuable feedback from your experiences!