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Running WRF LES with non periodic lateral boundary conditions

Hi, I am trying to run WRF LES case (em_les) with non periodic lateral boundary condition at the west,east lateral faces. The boundary condition at the west face would be a uniform inflow of 10m/s and the outlet would be zeroGradient as in Openfoam. Is this possible to do without changing any code?
 
Hi @Ming Chen, I had a followup question about how the input sounding works in the LES case. I have given it a value of 5m/s in the east west direction. Also, the domain is open at the east and west faces. Does the input_sounding force the flow to follow the vertical profile at the inlet or throughout the domain or does it act like a tendency term?
 
Hi,
In this case the input sounding will only provide initial condition throughout the domain. Once the model starts, the 5m/s wind will no longer has any impact on the model simulation, that is, it doesn't force any flow at the inlet and it doesn't behave as a tendency term.
 
My understanding is that there is no lateral boundary update by the input sounding once WRF-LES starts running.
 
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Hi @Ming Chen , thanks again for the quick reply. In the tech manual, the numerical implementation of the open lateral boundary conditions, there is a mention of the phase speed at the west and east faces. Is the phase speed hardcoded somewhere in the module files?
 
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Please take a look at the code share/module_bc.F, which contains the code to process open lateral boundary condition.
 
Hey Ming,
Quick followup question! In the input sounding we provide the heights, potential temperatures right? Are these values maintained through the duration of the simulation. Also are they the base potential temperature?
I am unable to find fields of the base state potential temperatures in the output nc file of the WRF LES simulation that I have run. My final goal is to find the density field by using the potential temperature relation to find the base state temperature field and then using the ideal gas law to estimate the density field. I am not sure if this is the right way to obtain the density field. Please help me!
 
Hey Ming,
Quick followup question! In the input sounding we provide the heights, potential temperatures right? Are these values maintained through the duration of the simulation. Also are they the base potential temperature?

No, they are treated as initial condition for the LES run. Once wrf.exe starts, the physics/dynamics will evolve and lead to changes in all the fields.
The temperature in the input sounding is not base potential temperature.
I am unable to find fields of the base state potential temperatures in the output nc file of the WRF LES simulation that I have run. My final goal is to find the density field by using the potential temperature relation to find the base state temperature field and then using the ideal gas law to estimate the density field. I am not sure if this is the right way to obtain the density field. Please help me!
I am not quite clear why you want to go through the steps to obtain density.
Please look at the variable 'alt' defined in Registry, which is the inverse density (unit: m3/kg). is this the variable you need?
 
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