example.config

# Configuration file for turtleFSI
[Parameter for turtleFSI] # Section is required by configargparse but is not used anywhere in turtleFSI
################################################################################
# Define solver, numerics, and problem file
################################################################################

# Name of problem file to solve. Could either be located in the turtleFSI
# repository (TF_cfd, TF_csm, TF_fsi, turtle_demo) or it could be a problem
# file you have created locally.
problem="turtle_demo"

# Setting temporal integration.
# (theta=0 : first order explicit forward Euler scheme)
# (theta=1 : first order implicit backward Euler scheme)
# (theta=0.5 : second-order Crank-Nicolson scheme)
# (theta=0.5+dt : gives a better long-term numerical stability while keeping
# the second order accuracy of the Crank-Nicolson scheme)
theta=0.501

################################################################################
# Set fluid, solid, and extrapolation
################################################################################

# Turn on/off solving of the fluid problem ('fluid', 'no_fluid')
fluid=fluid

# Turn on/off solving of the solid problem ('solid', 'no_solid')
solid=solid

# Use Robin boundary conditions for solid
robin_bc=False

# Set approach for extrapolating the deformation into the fluid domain
# ('laplace', 'elastic', 'biharmonic', 'no_extrapolation')
extrapolation=laplace

# Set the sub type of the extrapolation method ('constant'," 'small_constant',
# 'volume', 'volume_change', 'constrained_disp', 'constrained_disp_vel')
extrapolation-sub-type=constant

# List of boundary ids for the weak formulation of the biharmonic mesh lifting
# operator with 'constrained_disp_vel'
#bc_ids=[]

################################################################################
# Material settings / physical constants
################################################################################

# Maximum velocity at inlet
Um=0.8

# Density of the fluid
rho-f=1.0E3

# Fluid dynamic viscosity
mu-f=1.0

# Density of the solid
rho-s=1.0E3

# Shear modulus or 2nd Lame Coef. for the solid
mu-s=5.0E4

# Poisson ratio in the solid
nu-s=0.45

# 1st Lame Coef. for the solid
lambda-s=4.5E5

# Elastic response necessary for RobinBC
k_s=0.0

# Viscoelastic response necessary for RobinBC
c_s=0.0

# Gravitational force on the solid
#gravity=None

################################################################################
# Domain settings
################################################################################

# Domain id of the fluid domain
dx-f-id=1

# Domain id of the solid domain
dx-s-id=2

# Domain id of the solid boundary necessary for RobinBC
#ds_s_id=None

################################################################################
# Solver settings
################################################################################

# Selected linear solver for each Newton iteration, to see a complete list
# run list_linear_solvers()
linear-solver=mumps

# Absolute error tolerance for the Newton iterations
atol=1e-7

# Relative error tolerance for the Newton iterations
rtol=1e-7

# Maximum number of iterations in the Newton solver
max-it=50

# Relaxation factor in the Netwon solver
lmbda=1.0

# How often to recompute the Jacobian over Newton iterations
recompute=5

# How often to recompute the Jacobian over time steps.
recompute-tstep=1

# Update the default values of the compiler arguments by providing a key=value,
# e.g. optimize=False. You can provide multiple key=value pairs seperated by a
# whitespace
#compiler-parameters=None

################################################################################
# Output settings
################################################################################

# Turn on/off verbose printing
verbose=True

# Set FEniCS loglevel
loglevel=20

# Saving frequency of the files defined in the problem file
save-step=10

# Degree of the functions saved for visualisation. '1':P1, '2':P2, etc...
save-deg=1

# How often to store a checkpoint (use to later restart a simulation)
checkpoint-step=500

# Path to store the results. You can store multiple simulations in one folder
folder=results

# Over write the standard 1, 2, 3 name of the sub folders
#sub-folder=None

# Path to subfolder to restart from
#restart-folder=None

################################################################################
# Set spatial and temporal resolution
################################################################################

# Set timestep, dt
time-step=0.001

# Set end time
end-time=1

# Set degree of pressure
p-deg=1

# Set degree of velocity
v-deg=2

# Set degree of deformation
d-deg=2

################################################################################
# Misc settings
################################################################################

# Stop simulations cleanly after the given number of seconds
#killtime=None