Time-marching

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TIME_MARCHING

Unsteady simulation

More in config_template.cfg: Unsteady simulation (NO, TIME_STEPPING, DUAL_TIME_STEPPING-1ST_ORDER, DUAL_TIME_STEPPING-2ND_ORDER, HARMONIC_BALANCE)

Type: one of the values below
Values: NO, TIME_STEPPING, DUAL_TIME_STEPPING-1ST_ORDER, DUAL_TIME_STEPPING-2ND_ORDER, HARMONIC_BALANCE, ROTATIONAL_FRAME
Default: NO
In config_template.cfg: TIME_MARCHING= NO
Mentioned in: Guide to Version v7, Hybrid RANS/LES (DES), Setup Guide: Heat Transfer and Conjugate Heat Transfer, Setup Guide: Incompressible Flows, Setup Guide: Unsteady Flows and DES, Solver Setup and 5 more
Used in 70 test case files, for example: aeroelastic_NACA64A010.cfg (DUAL_TIME_STEPPING-2ND_ORDER), cylinder.cfg (DUAL_TIME_STEPPING-1ST_ORDER), HB.cfg (HARMONIC_BALANCE)
Code: CConfig.cpp line 1901

CFL_NUMBER

Courant-Friedrichs-Lewy condition of the finest grid

More in config_template.cfg: CFL number (initial value for the adaptive CFL number)

Type: real number
Default: 1.25
In config_template.cfg: CFL_NUMBER= 15.0
Mentioned in: Setup Guide: Heat Transfer and Conjugate Heat Transfer, Setup Guide: Incompressible Flows, Setup Guide: Laminar-Turbulent Transition, Setup Guide: Non-Ideal Compressible Flows, Setup Guide: Shape Optimization with the Discrete Adjoint, Setup Guide: Species Transport and Combustion and 8 more
Used in 372 test case files, for example: aeroelastic_NACA64A010.cfg (100.0), air_nozzle_restart.cfg (1000.0), backwardStep.cfg (2.0)
Code: CConfig.cpp line 1903

MAX_DELTA_TIME

Max time step in local time stepping simulations

More in config_template.cfg: Maximum Delta Time in local time stepping simulations

Type: real number
Default: 1000000
In config_template.cfg: MAX_DELTA_TIME= 1E6
Mentioned in: Setup Guide: Non-Ideal Compressible Flows
Used in 35 test case files, for example: air_nozzle_restart.cfg (1E6), solid.cfg (1.0), def_NACA4412.cfg (1E10)
Code: CConfig.cpp line 1905

OUTLIER_MITIGATION_PARAM

! DESCRIPTION: Parameters of the outlier mitigation strategy: start iteration, update frequency, print frequency, and number of standard deviations (N sigma) to identify outliers statistically.

More in config_template.cfg: For the compressible solver only (EULER, NS, RANS). Detect non-physical solutions statistically instead of relying just on zero or negative pressure or temperature, treat all points where temperature is further than N standard deviations from the mean as non-physical (MUSCL off and potentially higher dissipation). Strategy starts at inner iteration I, mean and sigma update every F, and distribution is printed every P updates.

Type: fixed-size list of integers
Default: Not extracted; see the code.
In config_template.cfg: % OUTLIER_MITIGATION_PARAM= (I, F, P, N). With the default start iteration this is essentially off.
Code: CConfig.cpp line 1910

CFL_ADAPT

Activate The adaptive CFL number.

More in config_template.cfg: Adaptive CFL number (NO, YES)

Type: YES / NO
Default: NO
In config_template.cfg: CFL_ADAPT= NO
Mentioned in: Setup Guide: Incompressible Flows, Setup Guide: Laminar-Turbulent Transition, Setup Guide: Non-Ideal Compressible Flows, Setup Guide: Species Transport and Combustion, Setup Guide: Steady RANS for External Aerodynamics, Setup Guide: Unsteady Flows and DES and 3 more
Used in 254 test case files, for example: air_nozzle_restart.cfg (NO), config.cfg (YES)
Code: CConfig.cpp line 1912

CFL_ADAPT_PARAM

! DESCRIPTION: Parameters of the adaptive CFL number (factor down, factor up, CFL limit (min and max)[, acceptable linear residual][, starting iteration]). Parameters in square brackets are optional, parameter “starting iteration” only valid with parameter “acceptable linear residual”. Factor down generally <1.0, factor up generally > 1.0 to cause the CFL to increase when the under-relaxation parameter is 1.0 and to decrease when the under-relaxation parameter is less than 0.1. Factor is multiplicative.

More in config_template.cfg: Parameters of the adaptive CFL number (factor-down, factor-up, CFL min value, CFL max value, acceptable linear solver convergence, starting iteration) After the starting iteration has passed, local CFL increases by factor-up until max if the solution rate of change is not limited, and acceptable linear convergence is achieved. It is reduced if rate is limited, or if there is not enough linear convergence, or if the nonlinear residuals are stagnant and oscillatory. It is reset back to min when linear solvers diverge, or if nonlinear residuals increase too much.

Type: list of real numbers
In config_template.cfg: CFL_ADAPT_PARAM= ( 0.1, 2.0, 10.0, 1e10, 0.001, 0)
Mentioned in: Changes in Version 8, Setup Guide: Incompressible Flows, Setup Guide: Laminar-Turbulent Transition, Setup Guide: Non-Ideal Compressible Flows, Setup Guide: Species Transport and Combustion, Setup Guide: Steady RANS for External Aerodynamics and 3 more
Used in 203 test case files, for example: config.cfg (( 0.5, 1.01, 1.0, 5, 0.0001)), inv_NACA0012.cfg (( 1.5, 0.5, 1.0, 100.0 )), flow_cylinder.cfg (( 1.5, 0.5, 10.0, 10000.0 ))
Code: CConfig.cpp line 1924

CFL_REDUCTION_ADJFLOW

Reduction factor of the CFL coefficient in the adjoint problem

Type: real number
Default: 0.8
In config_template.cfg: CFL_REDUCTION_ADJFLOW= 0.8
Mentioned in: Setup Guide: Shape Optimization with the Discrete Adjoint, Unconstrained shape design of a transonic inviscid airfoil at a cte. AoA
Used in 61 test case files, for example: inv_NACA0012.cfg (0.5), inv_wedge_ROE.cfg (0.8), lam_cylinder.cfg (0.75)
Code: CConfig.cpp line 1926

CFL_REDUCTION_TURB

Reduction factor of the CFL coefficient in the level set problem

More in config_template.cfg: Reduction factor of the CFL coefficient in the turbulence problem

Type: real number
Default: 1.0
In config_template.cfg: CFL_REDUCTION_TURB= 1.0
Mentioned in: Setup Guide: Laminar-Turbulent Transition, Setup Guide: Species Transport and Combustion, Setup Guide: Steady RANS for External Aerodynamics
Used in 67 test case files, for example: air_nozzle_restart.cfg (1.0), turb_SST_RAE2822.cfg (0.5), aachen_3D_MP_restart.cfg (0.1)
Code: CConfig.cpp line 1928

CFL_REDUCTION_ADJTURB

Reduction factor of the CFL coefficient in the turbulent adjoint problem

More in config_template.cfg: Reduction factor of the CFL coefficient in the adjoint turbulent problem

Type: real number
Default: 1.0
In config_template.cfg: CFL_REDUCTION_ADJTURB= 0.01
Used in 1 test case file, for example: transonic_stator.cfg (0.01)
Code: CConfig.cpp line 1930

CFL_REDUCTION_SPECIES

Reduction factor of the CFL coefficient in the species problem

Type: real number
Default: 1.0
In config_template.cfg: CFL_REDUCTION_SPECIES= 1.0
Mentioned in: Setup Guide: Species Transport and Combustion, Species Transport
Used in 24 test case files, for example: lam_prem_ch4_cfd.cfg (1.0), species2_primitiveVenturi_mixingmodel_TURBULENT_MARKERS.cfg (0.1)
Code: CConfig.cpp line 1932

EXT_ITER_OFFSET

External iteration offset due to restart

Type: integer
Default: 0
In config_template.cfg: EXT_ITER_OFFSET= 0
Code: CConfig.cpp line 1934

RK_ALPHA_COEFF

Runge-Kutta alpha coefficients

Type: list of real numbers
In config_template.cfg: RK_ALPHA_COEFF= ( 0.66667, 0.66667, 1.000000 )
Used in 150 test case files, for example: backwardStep.cfg (( 0.66667, 0.66667, 1.000000 )), InviscidVortex.cfg (( 0.666667, 0.666667, 1.0 )), fem_NACA0012.cfg (( 0.666667, 0.666667 , 1.0 ))
Code: CConfig.cpp line 1937

LEVELS_TIME_ACCURATE_LTS

Number of time levels for time accurate local time stepping.

More in config_template.cfg: Number of time levels for time accurate local time stepping. (1 by default, max. allowed 15)

Type: integer
Default: 1
In config_template.cfg: LEVELS_TIME_ACCURATE_LTS= 1
Used in 2 test case files, for example: fem_Sphere_reg_ADER.cfg (4), fem_unst_cylinder_ADER.cfg (8)
Code: CConfig.cpp line 1939

TIME_DOFS_ADER_DG

Number of time DOFs used in the predictor step of ADER-DG.

More in config_template.cfg: Number of time DOFs for the predictor step of ADER-DG (2 by default)

Type: integer
Default: 2
In config_template.cfg: TIME_DOFS_ADER_DG= 2
Used in 2 test case files, for example: fem_Sphere_reg_ADER.cfg (3)
Code: CConfig.cpp line 1941

UNST_CFL_NUMBER

Unsteady Courant-Friedrichs-Lewy number of the finest grid

Type: real number
Default: 0.0
In config_template.cfg: UNST_CFL_NUMBER= 0.0
Mentioned in: Setup Guide: Unsteady Flows and DES
Used in 11 test case files, for example: backwardStep.cfg (0.0), fem_Sphere_reg_ADER.cfg (0.15), fem_unst_cylinder.cfg (0.05)
Code: CConfig.cpp line 1943

TIME_INSTANCES

Integer number of periodic time instances for Harmonic Balance

Type: integer
Default: 1
In config_template.cfg: TIME_INSTANCES= 1
Used in 2 test case files, for example: HB.cfg (3), davis.cfg (7)
Code: CConfig.cpp line 1945

HB_PERIOD

Time period for Harmonic Balance wihtout moving meshes

Type: real number
Default: -1.0
In config_template.cfg: HB_PERIOD= -1
Used in 2 test case files, for example: HB.cfg (0.05891103435003335), davis.cfg (0.057465)
Code: CConfig.cpp line 1947

HB_PRECONDITION

Turn on/off harmonic balance preconditioning

Type: YES / NO
Default: NO
In config_template.cfg: HB_PRECONDITION= NO
Used in 1 test case file, for example: davis.cfg (YES)
Code: CConfig.cpp line 1949

UNST_ADJOINT_ITER

Starting direct solver iteration for the unsteady adjoint

Type: integer
Default: 0
In config_template.cfg: UNST_ADJOINT_ITER= 0
Mentioned in: Unsteady Shape Optimization NACA0012
Used in 18 test case files, for example: chtMaster.cfg (56), inv_NACA0012_pitching.cfg (151), inv_NACA0012_pitching_deform.cfg (5)
Code: CConfig.cpp line 1951

ITER_AVERAGE_OBJ

Number of iterations to average the objective

More in config_template.cfg: Number of iterations to average the objective function for unsteady adjoints, 0 averages over all time iterations, “N” averages over the last N iterations.

Type: integer
Default: 0
In config_template.cfg: ITER_AVERAGE_OBJ= 0
Mentioned in: Unsteady Shape Optimization NACA0012
Used in 9 test case files, for example: chtMaster.cfg (54), config.cfg (3), cylinder.cfg (10)
Code: CConfig.cpp line 1953

TIME_DISCRE_FLOW

Time discretization

More in config_template.cfg: Time discretization (RUNGE-KUTTA_EXPLICIT, EULER_IMPLICIT, EULER_EXPLICIT)

Type: one of the values below
Values: RUNGE-KUTTA_EXPLICIT, EULER_EXPLICIT, EULER_IMPLICIT, CLASSICAL_RK4_EXPLICIT, ADER_DG
Default: EULER_IMPLICIT
In config_template.cfg: TIME_DISCRE_FLOW= EULER_IMPLICIT
Mentioned in: Setup Guide: Heat Transfer and Conjugate Heat Transfer, Setup Guide: Incompressible Flows, Setup Guide: Laminar-Turbulent Transition, Setup Guide: Shape Optimization with the Discrete Adjoint, Setup Guide: Species Transport and Combustion, Setup Guide: Steady RANS for External Aerodynamics and 4 more
Used in 325 test case files, for example: aeroelastic_NACA64A010.cfg (EULER_IMPLICIT), inv_channel_RK.cfg (RUNGE-KUTTA_EXPLICIT), InviscidVortex.cfg (CLASSICAL_RK4_EXPLICIT)
Code: CConfig.cpp line 1955

TIME_DISCRE_FEM_FLOW

Time discretization

More in config_template.cfg: Time discretization (RUNGE-KUTTA_EXPLICIT, CLASSICAL_RK4_EXPLICIT, ADER_DG)

Type: one of the values below
Values: RUNGE-KUTTA_EXPLICIT, EULER_EXPLICIT, EULER_IMPLICIT, CLASSICAL_RK4_EXPLICIT, ADER_DG
Default: RUNGE-KUTTA_EXPLICIT
In config_template.cfg: TIME_DISCRE_FEM_FLOW= RUNGE-KUTTA_EXPLICIT
Used in 35 test case files, for example: InviscidVortex.cfg (CLASSICAL_RK4_EXPLICIT), fem_NACA0012.cfg (RUNGE-KUTTA_EXPLICIT), fem_Sphere_reg_ADER.cfg (ADER_DG)
Code: CConfig.cpp line 1957

ADER_PREDICTOR

ADER-DG predictor step

More in config_template.cfg: Type of discretization used in the predictor step of ADER-DG (ADER_ALIASED_PREDICTOR, ADER_NON_ALIASED_PREDICTOR)

Type: one of the values below
Values: ADER_ALIASED_PREDICTOR, ADER_NON_ALIASED_PREDICTOR
Default: ADER_ALIASED_PREDICTOR
In config_template.cfg: ADER_PREDICTOR= ADER_ALIASED_PREDICTOR
Used in 2 test case files, for example: fem_Sphere_reg_ADER.cfg (ADER_ALIASED_PREDICTOR)
Code: CConfig.cpp line 1959

TIME_DISCRE_ADJFLOW

Time discretization

More in config_template.cfg: Time discretization (RUNGE-KUTTA_EXPLICIT, EULER_IMPLICIT)

Type: one of the values below
Values: RUNGE-KUTTA_EXPLICIT, EULER_EXPLICIT, EULER_IMPLICIT, CLASSICAL_RK4_EXPLICIT, ADER_DG
Default: EULER_IMPLICIT
In config_template.cfg: TIME_DISCRE_ADJFLOW= EULER_IMPLICIT
Mentioned in: Unconstrained shape design of a transonic inviscid airfoil at a cte. AoA
Used in 61 test case files, for example: inv_NACA0012.cfg (EULER_IMPLICIT)
Code: CConfig.cpp line 1961

TIME_DISCRE_TURB

Time discretization

More in config_template.cfg: Time discretization (EULER_IMPLICIT, EULER_EXPLICIT)

Type: one of the values below
Values: RUNGE-KUTTA_EXPLICIT, EULER_EXPLICIT, EULER_IMPLICIT, CLASSICAL_RK4_EXPLICIT, ADER_DG
Default: EULER_IMPLICIT
In config_template.cfg: TIME_DISCRE_TURB= EULER_IMPLICIT
Mentioned in: Setup Guide: Laminar-Turbulent Transition, Setup Guide: Steady RANS for External Aerodynamics, Setup Guide: Unsteady Flows and DES, Turbulent Flat Plate
Used in 126 test case files, for example: air_nozzle_restart.cfg (EULER_IMPLICIT), turb_NACA0012_sst_expliciteuler.cfg (EULER_EXPLICIT)
Code: CConfig.cpp line 1963

TIME_DISCRE_ADJTURB

Time discretization

More in config_template.cfg: Time discretization (EULER_IMPLICIT)

Type: one of the values below
Values: RUNGE-KUTTA_EXPLICIT, EULER_EXPLICIT, EULER_IMPLICIT, CLASSICAL_RK4_EXPLICIT, ADER_DG
Default: EULER_IMPLICIT
In config_template.cfg: TIME_DISCRE_ADJTURB= EULER_IMPLICIT
Used in 1 test case file, for example: transonic_stator.cfg (EULER_IMPLICIT)
Code: CConfig.cpp line 1965

TIME_DISCRE_SPECIES

Time discretization for species equations

More in config_template.cfg: Time discretization for species equations (EULER_IMPLICIT, EULER_EXPLICIT)

Type: one of the values below
Values: RUNGE-KUTTA_EXPLICIT, EULER_EXPLICIT, EULER_IMPLICIT, CLASSICAL_RK4_EXPLICIT, ADER_DG
Default: EULER_IMPLICIT
In config_template.cfg: TIME_DISCRE_SPECIES= EULER_IMPLICIT
Mentioned in: Setup Guide: Species Transport and Combustion, Composition-Dependent model for Species Transport equations, Species Transport
Used in 29 test case files, for example: lam_prem_ch4_cfd.cfg (EULER_IMPLICIT)
Code: CConfig.cpp line 1967

TIME_DISCRE_FEA

Time discretization

Type: one of the values below
Values: NEWMARK_IMPLICIT
Default: NEWMARK_IMPLICIT
In config_template.cfg: TIME_DISCRE_FEA= NEWMARK_IMPLICIT
Mentioned in: Changes in Version 8, Linear Dynamics
Used in 6 test case files, for example: configFEA.cfg (NEWMARK_IMPLICIT)
Code: CConfig.cpp line 1969

TIME_DISCRE_RADIATION

Time discretization for radiation problems

More in config_template.cfg: Time discretization for radiation problems (EULER_IMPLICIT)

Type: one of the values below
Values: RUNGE-KUTTA_EXPLICIT, EULER_EXPLICIT, EULER_IMPLICIT, CLASSICAL_RK4_EXPLICIT, ADER_DG
Default: EULER_IMPLICIT
In config_template.cfg: TIME_DISCRE_RADIATION = EULER_IMPLICIT
Code: CConfig.cpp line 1971

TIME_DISCRE_HEAT

Time discretization

Type: one of the values below
Values: RUNGE-KUTTA_EXPLICIT, EULER_EXPLICIT, EULER_IMPLICIT, CLASSICAL_RK4_EXPLICIT, ADER_DG
Default: EULER_IMPLICIT
In config_template.cfg: TIME_DISCRE_HEAT= EULER_IMPLICIT
Mentioned in: Setup Guide: Heat Transfer and Conjugate Heat Transfer
Used in 25 test case files, for example: solid_cylinder1.cfg (EULER_IMPLICIT)
Code: CConfig.cpp line 1973

TIMESTEP_HEAT

Time discretization

Type: one of the values below
Values: LOCAL, CONVECTIVE, VISCOUS, BYFLOW
Default: LOCAL
Not in config_template.cfg.
Mentioned in: Setup Guide: Heat Transfer and Conjugate Heat Transfer
Code: CConfig.cpp line 1975

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