hydep.cfg.example

# Example configuration file for hydep
# Follows the INI / CFG (loose) specification
# This file is not used by the framework, but is provided as a
# template and starting point

# Values are expected to be of the form
# key = value
# where key can include spaces
# Anything after a # symbol is considered


# Booleans can be retrieved in a variety of ways.
# The following options (case insensitive) will evaluate to True:
# 1 yes y true
# The following options (case insensitive) will evaluate to False:
# 0 no n false

# Sections are used to configure various solvers
# and are differentiated with
# [section]

# The main section that must occur
[hydep]
# Values here are intended to be used by some or all solvers

## boundary condition
# Allowable values:
# reflective, vacuum, periodic
# Default: vacuum in all directions
# Can be delimited by commas or spaces.
# Must contain one or three values.
# A single value will be applied to all directions
# For the case of three values, the conditions will be applied
# to the x, y, and z dimension
boundary conditions = reflective vacuum reflective

## basedir
# Path to where the final results should be saved
# Default: save to current working directory
# If provided, must be able to produce an absolute path
# to a directory. If the directory does not exist,
# it will be created
basedir = example/base

## depletion solver
# String indicating what depletion solver to use.
# Currently allowed values are (case insensitive)
# cram16, 16, cram48, 48
# to use the 16th and 48th order Chebyshev Rational Approximation
# method (incomplete partial factorization)
depletion solver = 48

## fitting order
# Non-negative integer for the maximum polynomial fitting to be 
# used when projecting microscopic cross sections and other
# data forwards in time. Used in the depletion engine to compute
# reaction rates at substeps, as well as the SFV solver.
# Defaults to linear, but be careful using linear or above for
# large steps (<20 days) without sufficient previous points
# Fitting routines will the maximum order up to this value, depending
# on the number of time points possible. For the first coarse step,
# there will only be a single point of reference data and thus a 
# linear fit will not be possible.
fitting order = 0

## fitting points
# Positive integer for the number of values to store when constructing
# polynomial fits. Must be greater than fitting order, defaults to three.
# Older values are pushed out as newer values arrive.
# More points increase memory use, and too many points may be detrimental.
# Previous experience indicates that two or three points may be sufficient
fitting points = 2

## rundir
# Directory where the simulations will be run
# Default behavior is determined by basedir and
# use temp dir setting.
# Simulations will create auxiliary files in this directory
# If provided, it must resolve to an absolute path to a 
# directory. If a directory is provided and it does not exist,
# it will be created
# If not provided, will be set to
# - a temporary directory if use temp dir is true, or
# - basedir
rundir = example/run

## use temp dir
# Boolean switch to run simulations in a temporary directory
# Will only be used if rundir is not provided
# Temporary directory will be created, managed, and removed
# by the program
# Simulations will be run in this temporary directory, and 
# any auxiliary files not archived will be lost
use temp dir = false

# Solver-specific options are expected to be in a "subsection"
# [hydep.<solver>]
# Two solvers are provided with this framework, and detailed below

[hydep.serpent]
# Configuring the Serpent interface

## datadir
# Absolute path to the directory that contains Serpent nuclear
# data files like acelib, declib, and nfylib. If not provided,
# attempt to obtain the SERPENT_DATA environment variable.
# Otherwise, must resolve to an existing absolute path to a directory
# datadir = 

## acelib
# Path to the primary cross section lookup file.
# Must eventually be provided, and can be an absolute path to an existing
# file, or a path relative to datadir (or SERPENT_DATA). Regardless,
# it must resolve to an absolute path to an existing file.
acelib = sss_endfb7u.xsdata

## declib
# Path to decay library
# Must eventually be provided, and can be an absolute path to an existing
# file, or a path relative to datadir (or SERPENT_DATA). Regardless,
# it must resolve to an absolute path to an existing file.
declib = sss_endfb71.dec

## nfylib
# Path to neutron induced fission product yield file
# Must eventually be provided, and can be an absolute path to an existing
# file, or a path relative to datadir (or SERPENT_DATA). Regardless,
# it must resolve to an absolute path to an existing file.
nfylib = sss_endfb71.nfy

## thermal scattering
# Path to S(a,b) scattering file
# Not necessary unless a material requires the data, indicated by a call to
# Material.addSAlphaBeta(name)
# If provided and needed, it must resolve to an absolute path to an existing
# file containing S(a,b) data. If it is not provided and it is needed, then
# the following locations will be tried
# datadir/acedata/sssth1
# $(SERPENT_DATA)/acedata/sssth1
# If none of these files exist, and the scattering data are needed, an error
# will be raised
# thermal scattering = 

## particles
# Positive integer with the number of particle to simulate each cycle.
# There is no default, and a value must be provided, or else the
# simulation will fail
particles = 5E6

## generations per batch
# Positive integer for the number of generations (or cycles) per a single
# batch. Used to compute the total number of active and inactive cycles.
# There is no default, and a value must be provided, or else the
# simulation will fail
generations per batch = 10

## active
# Positive integer for the number of active **batches** to simulate.
# The number of active cycles will be active * generations per batch
# There is no default, and a value must be provided, or else the
# simulation will fail
active = 20

## inactive
# Positive integer for the number of inactive **batches** to simulate.
# The number of inactive cycles will be inactive * generations per batch.
# There is no default, and a value must be provided, or else the
# simulation will fail
inactive = 15

## seed
# Positive integer for an initial random seed. Not required, and no default
seed = 123456

## k0
# Initial guess for the multiplication factor. Must be a float between
# 0 and 2, exclusive. Not required, and defaults to 1.0
k0 = 1.2

## executable
# Name or path to the serpent executable. Will be used to form the command
# that runs Serpent using subprocess.run / subprocess.Popen.
# There is no default, and one must be provided or else nothing can be run
executable = sss2

## omp
# Positive integer for the number of parallel threads to use. If not
# provided, attempt to pull from OMP_NUM_THREADS environment variable.
# Otherwise the default is to run with a single thread.
omp = 16

## mpi
# Positive integer for the number of MPI tasks to use when executing
# Serpent. Will prepend "mpirun -np <mpi>" to the execution command.
# The default is run with in serial, with or without omp threads as
# determined by the omp setting
mpi = 2

## Fission product yields
# Two settings control how Serpent handles FPY
# The main setting in "fpy mode", which can be constant
# or weighted. The weighted scheme will use local spectral
# information to produce a representative set of fission
# product yields for each fissile isotope in each burnable
# material. This will add additional detectors, but hopefully
# captures more of the physics
fpy mode = constant
# Constant mode will use a fixed set of yields to all isotopes
# regardless of local information. The default is to use a 
# set of thermal spectrum yields (corresponding to 0.0253 evaluate
# in evaluated data files), but this can be configured with
# the "fpy spectrum" setting to indicate "thermal", "epithermal",
# or "fast" yields 
fpy spectrum = fast

## Fission source passing
# Serpent allows the fission source to be passed between depletion
# steps, and reducing the number of inactive cycles at subsequent steps.
# This can be used to reduce the overall computational resources required,
# as fewer inactive cycles are needed to update the fission source.
# The setting
fsp inactive batches = 2
# can be used to activate this Serpent option. Note that this value,
# like the parameter for inactive and active, denotes batches, not cycles.
# The number of inactive cycles run at subsequent steps will be
# fsp batches * generations per batch. If given, must be a non-negative
# integer, ideally less than the number of inactive batches for the first
# transport solution. Not providing a value will have every Serpent solution
# start from a uniform fission source distribution.

[hydep.sfv]
# Configure the spatial flux variation solver

## modes
# Positive integer for the number of higher order flux modes to use
# when prediction the change in spatial flux. If not provided, the
# value will be determined using mode fraction. An error will be
# raised is this value exceeds the number of burnable materials
# in the problem. For maximum compatibility, it is recommended to
# use mode fraction unless you know how many modes are available
modes = 10

## mode fraction
# Real number bounded between (0, 1] for the fraction of available
# modes to use in the prediction. The default value of one will use
# all the available modes, while a value of 0.5 will use half.
mode fraction = 0.75

## density cutoff
# Non-negative density [atoms/b/cm] that isotopes must exceed when
# reconstructing macroscopic cross sections. Default value of 0.0
density cutoff = 1E-20