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rybchuk / amr-wind-tutorial

An unofficial guide on how to use AMR-Wind
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Flow behaving strange #4

Open AsimUdel opened 2 months ago

AsimUdel commented 2 months ago

Hi @rybchuk , I hope you are doing great. I wanted to discuss a problem which I am facing. i think it is flow reversal. https://github.com/rybchuk/amr-wind-tutorial/blob/main/03_turbines.md, here you explained that if the inflow is aligned in x direction purely, the "both the ylo and the yhi planes in the precursor simulation. Sometimes running with ylo isn't enough because a small amount of flow can enter the domain through yhi. This scenario can manifest as a simultion with a growing CFL error." I have tried previously also saving the precursor files in yhi too, but right now I did not save in yhi. I am attaching some plots, can you confirm you were referencing to this behavior of flow at (x output). I am attaching the input files too. No_turbine_unstable.txt precursor_unstable.txt spinup_unstable.txt Turbine_unstable.txt

Spinup: Spinup_hub_height_xy_unstable Precursor: Precursor_XY_hub_height Precusror_tke_xy

Turbine: Turbine_tke_xy Turbine_xy_plane

No turbine:

No_Turbine_xy_plane No_Turbine_tke_xy

P.S, I have asked at lawrence's github issue board too, since you mention this issue in your tutorial I really wanted to get help from you also. Thank you Asim

AsimUdel commented 1 month ago

Hello @rybchuk , Could you please explain a bit about the settings of "mass_inflow" and what is its relevance with T(temperature), U (velocity) and P (pressure) ? and also below are the settings for my precursor and turbine run respectively,

Precursor: " geometry.is_periodic = 1 1 0

xlo.type = mass_inflow

xlo.density = 1.225

xlo.temperature = 290.0

xlo.tke = 0.0

xhi.type = pressure_outflow

ylo.type = mass_inflow

ylo.density = 1.225

ylo.temperature = 290.0

ylo.tke = 0.0

yhi.type = pressure_outflow

zlo.type = wall_model zhi.type = slip_wall zhi.temperature_type = fixed_gradient zlo.temperature_type = zero_gradient zhi.temperature = 0.003 "

Turbine: " geometry.is_periodic = 0 0 0 xlo.type = mass_inflow
xlo.density = 1.225
xhi.type = pressure_outflow xlo.temperature_type = fixed_gradient xlo.temperature = 0.0 xlo.tke = 0 xlo.pressure_type = buoyant_pressure
ylo.type = mass_inflow
ylo.density = 1.225
yhi.type = pressure_outflow
yhi.temperature_type = fixed_gradient yhi.temperature = 0.0 ylo.temperature_type = fixed_gradient ylo.temperature = 0.0 ylo.tke = 0 zlo.type = wall_model zhi.type = slip_wall zhi.temperature_type = fixed_gradient zlo.temperature_type = zero_gradient zhi.temperature = 0.003"

What option should I use if I want to use the boundary values of U, T, and TKE saved from the precursor run? are these settings best possible I could set? Thank you Best Asim