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Child domain with same resolution as parent domain?

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New member
Hi all,

I'm wondering if it's possible to run an idealized LES case where the parent domain has the same grid resolution as the child domain? I'd like to run a simulation where the parent domain is periodic to spin-up turbulence and then the child domain is nested and contains a wind turbine. I cannot do this on a single domain because then the turbine wakes itself. I'd like continuous, fully-developed turbulence as inflow.

I've successfully used a parent grid ratio of 2 (I know this is not recommended). But by using a grid ratio of 1, I would be able to cut the computational expense significantly. I've tried an idealized case with a grid ratio of 1 but then WRF exits with no message in the rsl files. I've turned up the debug level and it fails after the initial output files are written but within the first time step. I've seen it fail "call surface_driver" but it's not clear how the grid ratio is causing the fail here. I've also seen it fail at "calling inc/" and another inc/ file depending on the number of nodes or grid cells.

Any tips or tricks would be appreciated.

I found that changing the interpolation method solves this issue. I changed the interpolation method from SINT (default) to NEAREST_NEIGHBOR (interp_method_type = 3 in the namelist) and my simulations have run without crashing.
Thanks for the kind message. This is helpful for people who try to run a nested case with the same resolution in parent and cild domain.