Input Files and Controls

The input file specified on the command line is a free-format text file, one entry per row, that specifies input data processed by the AMReX ParmParse module.

This file needs to specified along with the executable as an argv option, for example:

mpirun -np 64 ./marbles inputs

Entries can be overwritten on the command line: ./marbles inputs amr.plot_int=10.

Here is an example input file:

# maximum number of time steps at base AMR level
max_step = 1000

# coordinates of domain's lower corner
geometry.prob_lo = 0.0 0.0 0.0

# coordinates of domain's upper corner
geometry.prob_hi = 96.0 16.0 16.0

# flag for periodicity (here y direction is periodic)
geometry.is_periodic = 0 1 0

# number of cells along each direction at base level
amr.n_cell  = 96 16 16

# maximum level number allowed
amr.max_level = 0

# maximum number of cells per box along x,y,z
amr.max_grid_size = 16

# number of timesteps between plot files
amr.plot_int = 10

# number of timesteps between checkpoint files
amr.chk_int = 10

# LBM parameteris
lbm.bc_lo = 2 0 1
lbm.bc_hi = 3 0 1
lbm.dx_outer = 0.5
lbm.dt_outer = 0.5
lbm.nu = 0.01733333333333333
lbm.save_streaming = 0

lbm.velocity_bc_type = "channel"
velocity_bc_channel.u_ref = 0.1

lbm.ic_type = "constant"
ic_constant.density = 1.0
ic_constant.velocity = 0.0 0.0 0.0

# embedded boundary
eb2.geom_type = "cylinder"
eb2.cylinder_radius = 2.0
eb2.cylinder_center = 32.0 8.0 8.0
eb2.cylinder_has_fluid_inside = 0
eb2.cylinder_height = 256.0
eb2.cylinder_direction = 1

# amrex options for trapping FPEs
amrex.fpe_trap_invalid = 1
amrex.fpe_trap_zero = 1
amrex.fpe_trap_overflow = 1

Here is an examples of setting up tagging criteria:

# Tag inside a box and a velocity magnitude value
tagging.refinement_indicators = yLow vel_mag
tagging.yLow.in_box_lo = -0.1  -0.52  -0.85
tagging.yLow.in_box_hi =  3.1 -0.45    0.85

tagging.vel_mag.max_level     = 2
tagging.vel_mag.value_greater = 1.2e4
tagging.vel_mag.field_name    = vel_mag

The following keys are implemented: value_greater, value_less, adjacent_difference_greater, in_box_lo and in_box_hi (to specify a refinement region), max_level, start_time, and end_time. The field_name key can be any available variable.