AMR-Wind inputs file

To run amr_wind, the user must provide a text file containing inputs describing the problem and any additional command-line arguments that override the parameters in the input file for that particular invocation of the executable.

# Parse input parameters from `inputs.abl` but change max_step to 20
$ ./amr_wind inputs.abl time.max_step=20

The input file is a simple text file containing key = value entries for the input parameters. The text file can include comments, any text beginning with # till the end of line (EOF) is interpreted as comments and ignored by the parser. Input file processing is handled by AMReX ParmParse library. This section documents the various input file parameters and their default values (if available). In amr_wind, the input file is broken into sections indicated by a namespace prefix. For example, all inputs related to the problem domain are prefixed with geometry. and so on. A sample input file is shown below

# AMR-Wind example input file
#
# Atmospheric boundary layer (precursor) simulation
#

# Problem domain definition
geometry.prob_lo                            = 0.0 0.0 0.0
geometry.prob_hi                            = 5120.0 5120.0 1280.0
geometry.is_periodic                        = 1 1 0

# Mesh resolution and AMR definitions
amr.n_cell                                  = 512 512 128
amr.max_level                               = 0

# Simulation control parameters
time.stop_time                              = 20000.0
time.max_step                               = -1
time.fixed_dt                               = 0.5
time.cfl                                    = 0.95
time.init_shrink                            = 0.1
time.regrid_interval                        = -1
time.plot_interval                          = 1000
time.checkpoint_interval                    = 10000
time.use_force_cfl                          = false

# input/output settings
io.check_file                               = "chk"
io.plot_file                                = "plt"
io.restart_file                             = ""

# incflo
incflo.physics                              = ABL
incflo.density                              = 1.225
incflo.velocity                             = 6.0 5.0 0.0
incflo.verbose                              = 0
incflo.initial_iterations                   = 3
incflo.do_initial_proj                      = true
incflo.constant_density                     = true
incflo.use_godunov                          = 1
incflow.godunov_type                        = "ppm"
incflo.godunov_use_forces_in_trans          = false
incflo.diffusion_type                       = 2

# transport equation parameters
transport.model                             = ConstTransport
transport.viscosity                         = 1.0e-5
transport.laminar_prandtl                   = 0.7
transport.turbulent_prandtl                 = 0.333
transport.reference_temperature                   = 290.0

# turbulence equation parameters
turbulence.model                            = OneEqKsgsM84

# Atmospheric boundary layer
ABL.Uperiods                                = 4.0
ABL.Vperiods                                = 4.0
ABL.cutoff_height                           = 50.0
ABL.deltaU                                  = 1.0
ABL.deltaV                                  = 1.0
ABL.kappa                                   = .41
ABL.normal_direction                        = 2
ABL.perturb_ref_height                      = 50.0
ABL.perturb_temperature                     = true
ABL.perturb_velocity                        = true
ABL.stats_output_format                     = netcdf
ABL.stats_output_frequency                  = 1
ABL.surface_roughness_z0                    = 0.01
ABL.surface_temp_flux                       = 0.005
ABL.temperature_heights                     = 0.0 2000.0
ABL.temperature_values                      = 290.0 296.0

# momentum source term parameters
ICNS.source_terms                           = BoussinesqBuoyancy CoriolisForcing ABLForcing
ABLForcing.abl_forcing_height               = 90.0
CoriolisForcing.east_vector                 = 1.0 0.0 0.0
CoriolisForcing.latitude                    = 41.3
CoriolisForcing.north_vector                = 0.0 1.0 0.0
CoriolisForcing.rotational_time_period      = 86400.0
GeostrophicForcing.geostrophic_wind         = 10.0 0.0 0.0

# Boundary conditions
zhi.type                                    = "slip_wall"
zhi.temperature_type                        = "fixed_gradient"
zhi.temperature                             = 0.003
zlo.type                                    = "wall_model"
zlo.tke_type                                = "fixed_gradient"

# MLMG options for cell-centered diffusion solve
diffusion.mg_verbose                        = 0
diffusion.mg_cg_verbose                     = 0
diffusion.mg_max_iter                       = 200
diffusion.mg_cg_max_iter                    = 200
diffusion.mg_fmg_max_iter                   = 0
diffusion.mg_max_coarsening_level           = 100
diffusion.mg_max_order                      = 2
diffusion.mg_rtol                           = 1.0e-6
diffusion.mg_atol                           = 1.0e-12
diffusion.bottom_solver                     = "bicgstab"

# MLMG options for MAC Projection
mac_proj.mg_rtol                            = 1.0e-6
mac_proj.mg_atol                            = 1.0e-12

# MLMG options for Nodal Projection
nodal_proj.mg_rtol                          = 1.0e-6
nodal_proj.mg_atol                          = 1.0e-12

# Post processing algorithms
incflo.post_processing = sampling enstrophy ke

# Data probe sampling
sampling.output_frequency = 1
sampling.labels = l_v11 p_h
sampling.fields = velocity temperature

# sampling along a line
sampling.l_v11.type = LineSampler
sampling.l_v11.num_points = 192
sampling.l_v11.start = 500.0 500.0 5.0
sampling.l_v11.end = 500.0 500.0 1995.0

# Sampling on a plane
sampling.p_h.type = PlaneSampler
sampling.p_h.axis1 = 5210.0 0.0 0.0
sampling.p_h.axis2 = 0.0 5210.0 0.0
sampling.p_h.origin = 0.0 0.0 50.0
sampling.p_h.num_points = 288 288
sampling.p_h.normal = 0.0 0.0 1.0
sampling.p_h.offsets = 0.0 50.0 150.0

# kinetic energy and enstrophy integration
ke.type = KineticEnergy
ke.output_frequency = 1
enstrophy.type = Enstrophy
enstrophy.output_frequency = 1

Input file reference

The AMR-Wind input file is organized in the following sections

Section	Description
`geometry`	Computational domain information
`amr`	Mesh refinement controls
`tagging`	Static and dynamic refinement options
`time`	Simulation time controls
`io`	Input/Output controls
`incflo`	CFD algorithm and physics controls
`transport`	Transport equation controls
`turbulence`	Turbulence model controls
`ABL`	Atmospheric boundary layer (ABL) controls
`ABLMesoForcing`	Mesoscale ABL forcing controls
`SyntheticTurbulence`	Inject turbulence using body forces
`Momentum sources`	Activate Momentum source terms and their parameters
`Boundary conditions`	Boundary condition types and gradients
`MLMG options`	Multi-Level Multi-Grid Linear solver options
`Sampling`	Data probes to sample field data during simulations
`Averaging`	Time averaging and correlations

This section documents the parameters available within each section. Please note that the documentation provided here is for the latest major release of AMR-Wind. While input file specifications rarely change, major releases of AMR-Wind (e.g 2.x to 3.x) might have breaking changes and the documentation provided here might not work with older releases.

Note

Boolean flags (true/false) can also be indicated using integers in the text file and uses the convention 0 = False and 1 = True.
Quotes around strings are optional.
If an input is repeated only the last one is used.