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Hsi-Yu Schive edited this page Mar 8, 2024 · 58 revisions

Compilation Options

Related options: MODEL,   FLU_SCHEME,   LR_SCHEME,   RSOLVER,   DUAL_ENERGY,   NCOMP_PASSIVE_USER,   MHD,   COSMIC_RAY,   CR_DIFFUSION,   EOS,   BAROTROPIC_EOS  

Runtime Parameters

Parameters described on this page: OPT__BC_FLU_XM,   OPT__BC_FLU_XP,   OPT__BC_FLU_YM,   OPT__BC_FLU_YP,   OPT__BC_FLU_ZM,   OPT__BC_FLU_ZP,   GAMMA,   MOLECULAR_WEIGHT,   MU_NORM,   ISO_TEMP,   OPT__LR_LIMITER,   MINMOD_COEFF,   MINMOD_MAX_ITER,   OPT__1ST_FLUX_CORR,   OPT__1ST_FLUX_CORR_SCHEME,   DUAL_ENERGY_SWITCH,   OPT__SAME_INTERFACE_B,   OPT__FIXUP_FLUX,   OPT__FIXUP_ELECTRIC,   OPT__FIXUP_RESTRICT,   OPT__CORR_AFTER_ALL_SYNC,   OPT__NORMALIZE_PASSIVE,   OPT__INT_FRAC_PASSIVE_LR,   OPT__RESET_FLUID,   OPT__RESET_FLUID_INIT,   OPT__FREEZE_FLUID,   MIN_DENS,   MIN_PRES,   MIN_EINT,   OPT__CHECK_PRES_AFTER_FLU,   OPT__LAST_RESORT_FLOOR,   JEANS_MIN_PRES,   JEANS_MIN_PRES_LEVEL,   JEANS_MIN_PRES_NCELL,   GAMMA_CR,   CR_DIFF_PARA,   CR_DIFF_PERP,   CR_DIFF_MIN_B  

Other related parameters: DT__FLUID,   DT__FLUID_INIT,   DT__CR_DIFFUSION,   AUTO_REDUCE_DT,   FLU_GPU_NPGROUP,   AUTO_REDUCE_MINMOD_FACTOR  

Parameters below are shown in the format:   Name   (Valid Values)   [Default Value]

  • OPT__BC_FLU_XM   (1=periodic, 2=outflow, 3=reflecting, 4=user, 5=diode)   [none]

    • Description: Fluid boundary conditions on the -x face. For the user-specified (i.e., inflow) boundary conditions, edit src/Fluid/Flu_BoundaryCondition_User.cpp for the cell-centered fluid variables and src/Model_Hydro/MHD_BoundaryCondition_User.cpp for the face-centered magnetic field, respectively, when TESTPROB_ID=0 or a problem-specific function when TESTPROB_ID≠0.
    • Restriction: When adopting periodic conditions, they must be applied to both the -x and +x faces. Particles only support the periodic boundary conditions. When adopting any non-periodic boundary condition for fluid, particles will be removed when getting too close to the boundaries (see PAR_REMOVE_CELL ).

  • OPT__BC_FLU_XP   (1=periodic, 2=outflow, 3=reflecting, 4=user, 5=diode)   [none]

    • Description: Fluid boundary conditions on the +x face. See the description of OPT__BC_FLU_XM.
    • Restriction: See the restriction on OPT__BC_FLU_XM.

  • OPT__BC_FLU_YM   (1=periodic, 2=outflow, 3=reflecting, 4=user, 5=diode)   [none]

    • Description: Fluid boundary conditions on the -y face. See the description of OPT__BC_FLU_XM.
    • Restriction: See the restriction on OPT__BC_FLU_XM.

  • OPT__BC_FLU_YP   (1=periodic, 2=outflow, 3=reflecting, 4=user, 5=diode)   [none]

    • Description: Fluid boundary conditions on the +y face. See the description of OPT__BC_FLU_XM.
    • Restriction: See the restriction on OPT__BC_FLU_XM.

  • OPT__BC_FLU_ZM   (1=periodic, 2=outflow, 3=reflecting, 4=user, 5=diode)   [none]

    • Description: Fluid boundary conditions on the -z face. See the description of OPT__BC_FLU_XM.
    • Restriction: See the restriction on OPT__BC_FLU_XM.

  • OPT__BC_FLU_ZP   (1=periodic, 2=outflow, 3=reflecting, 4=user, 5=diode)   [none]

    • Description: Fluid boundary conditions on the +z face. See the description of OPT__BC_FLU_XM.
    • Restriction: See the restriction on OPT__BC_FLU_XM.

  • GAMMA   (>1.0)   [5.0/3.0]

    • Description: Ratio of specific heats (i.e., adiabatic index) in the ideal gas EoS.
    • Restriction: Only applicable when adopting the compilation option EOS=EOS_GAMMA. Does not support the isothermal EoS (i.e., GAMMA=1.0), for which one should adopt EOS=EOS_ISOTHERMAL.

  • MOLECULAR_WEIGHT   (>0.0)   [0.6]

    • Description: Mean molecular weight.
    • Restriction:

  • MU_NORM   (<0.0=m_H, 0.0=amu, >0.0=input manually in gram)   [-1.0]

  • ISO_TEMP   (>0.0)   [none]

    • Description: Temperature in kelvin for the isothermal equation of state.
    • Restriction: Only applicable when adopting the compilation option EOS=EOS_ISOTHERMAL.

  • OPT__LR_LIMITER   (-1→ set to default, 0=none, 1=van Leer, 2=generalized minmod, 3=van Albada, 4=van Leer+generalized minmod, 6=central, 7=Athena)   [-1]

    • Description: Slope limiter for data reconstruction. The coefficient of the generalized minmod limiter can be set by MINMOD_COEFF. 7=Athena mimics the extrema-preserving limiter implemented in Athena++.
    • Restriction: Only applicable when adopting the compilation option FLU_SCHEME=MHM/MHM_RP/CTU. 7=Athena must work with LR_SCHEME=PPM.

  • MINMOD_COEFF   (1.0 ≤ input ≤ 2.0)   [1.5]

    • Description: Coefficient of the generalized minmod limiter for data reconstruction (OPT__LR_LIMITER=2/4). Smaller values lead to more diffusive but also more stable solutions.
    • Restriction:

  • MINMOD_MAX_ITER   (0=off, ≥0=on)   [0]

    • Description: Maximum number of iterations to reduce MINMOD_COEFF when data reconstruction fails. It improves code stability but may break strict conservation.
    • Restriction:

  • OPT__1ST_FLUX_CORR   (<0 → set to default, 0=off, 1=3D, 2=3D+1D)   [2]

    • Description: Correct unphysical results (e.g., negative density or pressure) by recalculating the solutions of failed cells with only first-order accuracy in space and time. OPT__1ST_FLUX_CORR=1: only use dimensionally unsplit update. OPT__1ST_FLUX_CORR=2: use dimensionally unsplit update first; and if it fails, switch to dimensionally split update. The number of cells corrected by this option will be recorded in the file Record__NCorrUnphy.
    • Restriction: Only applicable when adopting the compilation option FLU_SCHEME=MHM/MHM_RP/CTU. MHD currently does not support 3D+1D. Be aware that this option may cause conservation errors.

  • OPT__1ST_FLUX_CORR_SCHEME   (<0 → set to default, 0=none, 1=Roe, 2=HLLC, 3=HLLE, 4=HLLD)   [1]

    • Description: Riemann solver for OPT__1ST_FLUX_CORR.
    • Restriction:

  • DUAL_ENERGY_SWITCH   (≥0.0)   [2e-2]

    • Description: Switch threshold of the dual energy formalism. Specifically, we enable the dual energy formalism for cells with Eint/Ekin  <  ξ, where Eint is gas internal energy, Ekin is gas kinematic energy, and ξ=DUAL_ENERGY_SWITCH.
    • Restriction: Only applicable when enabling the compilation option DUAL_ENERGY.

  • OPT__SAME_INTERFACE_B   (0=off, 1=on)   [0]

    • Description: Ensure adjacent patches on the same level have exactly the same magnetic field on their shared interfaces (including round-off errors). This option is mainly for debugging purposes.
    • Restriction:

  • OPT__FIXUP_FLUX   (0=off, 1=on)   [1]

    • Description: Correct the coarse-grid data by the fluxes on the coarse-fine boundaries.
    • Restriction:

  • OPT__FIXUP_ELECTRIC   (0=off, 1=on)   [1]

    • Description: Correct the coarse-grid magnetic field by the electric field on the coarse-fine boundaries.
    • Restriction: For MHD only.

  • OPT__FIXUP_RESTRICT   (0=off, 1=on)   [1]

    • Description: Correct the coarse-grid data by the volume-weighted average of the child patch data.
    • Restriction:

  • OPT__CORR_AFTER_ALL_SYNC   (-1=set to default, 0=off, 1=every step, 2=before dump)   [depend]

    • Description: Apply additional corrections when all levels are synchronized. See Fluid/Flu_CorrAfterAllSync.cpp for details. This functionality is mainly for achieving bitwise reproducibility. OPT__CORR_AFTER_ALL_SYNC=1: apply corrections after each root-level update. OPT__CORR_AFTER_ALL_SYNC=2: apply corrections before each data dump. The default depends on the compilation option GAMER_DEBUG.
    • Restriction: Must be turned on when enabling the compilation option BITWISE_REPRODUCIBILITY.

  • OPT__RESET_FLUID   (0=off, 1=on)   [0]

    • Description: Reset fluid variables after each update. It can be useful for adding sources or sinks to a simulation. To specify how to reset fluid variables, edit the source file src/Fluid/Flu_ResetByUser.cpp directly or add a specific routine to your test problem files. See Adding New Simulations for details.
    • Restriction:

  • OPT__RESET_FLUID_INIT   (<0 → set to OPT__RESET_FLUID, 0=off, 1=on)   [-1]

    • Description: Reset fluid variables during initialization. See OPT__RESET_FLUID for details.
    • Restriction:

  • OPT__FREEZE_FLUID   (0=off, 1=on)   [0]

    • Description: Do not evolve fluid variables at all. It can be useful for evolving particles in a static gravitational potential of fluid or wave dark matter.
    • Restriction:

  • OPT__CHECK_PRES_AFTER_FLU   (<0 → set to default, 0=off, 1=on)   [-1]

    • Description: Check unphysical pressure at the end of the fluid solver. If it is off, the code will only check internal energy. This is particularly useful for a complicated equation of state.
    • Restriction:

  • MIN_DENS   (≥0.0)   [0.0]

    • Description: Gas mass density floor.
    • Restriction:

  • MIN_PRES   (≥0.0)   [0.0]

    • Description: Gas pressure floor.
    • Restriction:

  • MIN_EINT   (≥0.0)   [0.0]

    • Description: Gas internal energy density floor.
    • Restriction:

  • JEANS_MIN_PRES   (0=off, 1=on)   [0]

    • Description: Employ a pressure floor in the hydrodynamic solver to ensure that the local Jeans length of all cells on all levels is resolved by at least a width equal to JEANS_MIN_PRES_NCELL cells on level JEANS_MIN_PRES_LEVEL.
    • Restriction: Only applicable when enabling the compilation option GRAVITY.

  • JEANS_MIN_PRES_LEVEL   (≥0; <0 → set to default)   [ MAX_LEVEL ]

  • JEANS_MIN_PRES_NCELL   (≥1)   [4]

  • GAMMA_CR   (>1.0)   [4.0/3.0]

    • Description: Effective adiabatic index of cosmic rays.
    • Restriction: Only applicable when enabling the compilation option COSMIC_RAY.

  • CR_DIFF_PARA   (≥0.0)   [0.0]

    • Description: Cosmic-ray diffusion coefficient parallel to the magnetic field.
    • Restriction: Only applicable when enabling the compilation option CR_DIFFUSION.

  • CR_DIFF_PERP   (≥0.0)   [0.0]

    • Description: Cosmic-ray diffusion coefficient perpendicular to the magnetic field.
    • Restriction: Only applicable when enabling the compilation option CR_DIFFUSION.

  • CR_DIFF_MIN_B   (none)   [0.0]

    • Description: Disable cosmic-ray diffusion locally when the magnetic field amplitude is smaller than this threshold.
    • Restriction: Only applicable when enabling the compilation option CR_DIFFUSION.

Remarks


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