SOLPS-ITER 3.1.1

Boundary conditions

BCENE BCENI BCPOT BCCON BCMOM
All
No condition
1
Constant value, gradient
3
Sheath conditions
3
Flux based
3
Decay length
2
Leakage conditions
2
Feedback for const value
5
Recommended when drifts are enabled Neoclassical theory Coupling with other codes Special Deprecated
1
Not yet implemented
3

BCENE

Specifying the type of electron energy or temperature boundary condition for each segment; makes use of ENEPAR to specify additional information, as indicated

No condition


  • 0: default, no boundary condition is applied
    default

Constant value, gradient


  • 1: prescribe the value of the electron temperature, ENEPAR(,1) specifies the temperature in eV
    const

  • 2: prescribe the gradient of the electron temperature, ENEPAR(,1) specifies the temperature gradient in eV.m-1
    const

  • 4: prescribe the value of the electron temperature, weakly a mixed boundary condition, ENEPAR(,1) specifies the temperature in eV and ENEPAR(,2) specifies the 'strength' of the boundary condition
    const

Sheath conditions


  • 3: sheath conditions, electron energy transmission, ENEPAR(,1) specifies an additional contribution to the energy transmission coefficient in addition to that of the potential difference [the sound speed used depends on settings of MOMPAR(,ISMAIN,2)]
    sheath

  • 12: sheath conditions, electron energy transmission coefficient, ENEPAR(,1) specifies an energy transmission factor, deltae in Qe = deltae Γe Te
    sheath

  • 15: sheath boundary condition, from b2stbc_spb, recommended when using drifts (see Section C.7.4 of manual for details). Linked to using BCCON=14 and BCMOM=13 for all ion species, BCENI=15, and BCPOT=11.
    sheath
    drifts

Flux based


  • 5: prescribe the electron energy flux per unit area, ENEPAR(,1) specifies the energy flux density in W.m-2
    flux

  • 8: prescribe the total electron heat flux with constant flux density, ENEPAR(,1) specifies the energy flux in W
    flux

  • 13: prescribe the electron energy flux per unit area proportional to temperature, ENEPAR(,1) specifies the energy flux density per temperature in W.m-2.J-1 (the temperature here in J)
    flux

Decay length


  • 9: prescribe the decay length for the electron temperature, ENEPAR(,1) specifies the decay length in m (can also use type [19] instead)
    decay_len

  • 19: same as [9] but to be used when simultaneously setting BCCON=1 on the same boundary.
    decay_len

Leakage conditions


  • 14: leakage option for electron energy, ENEPAR(,1) specifies the leakage factor, α in Γloss = α Cs, collective ne Te
    leakage

  • 22: radial leakage condition for the electron temperature. ENEPAR(,1) specifies the leakage velocity in units of the electron thermal velocity. A temperature gradient such that the diffusive flux is set to match this leakage is imposed.
    leakage

Feedback for const value


  • 10: feedback option for core, ENEPAR(,1) not used, derived from cbshe(0,coreregno)
    feedback

  • 16: feedback boundary condition with constant temperature, ENEPAR(,1) specifies the power flux in W across the flux surface with index 'b2stbc_type16_ref' (default=-1), ENEPAR(,2) should be something like 0.1 and specifies the strength of the feedback. Also see type [17] below. Available if bcene_16_style=0 (default). If bcene_16_style=1, integrated electron heat flux with constant electron temperature, summed over all core boundaries with BCENE=16.
    feedback

  • 17: feedback boundary condition with constant shared temperature for both electrons and ions, with ENEPAR(,1) + ENIPAR(,1) giving the total power flux in W across the flux surface with index 'b2stbc_type16_ref' (default=-1), ENEPAR(,2) should be something like 0.1 and specifies the strength of the feedback. Replaces [16] for high densities and large values of 'b2stbc_type16_ref'.
    feedback

  • 20: feedback boundary condition with constant temperature, as per type [16] but with 'type20_' switches and a different feedback scheme.
    feedback

  • 21: constant temperature feedback scaled by temperature on the ring bc_type21_ref away. ENEPAR(,1) specifies the desired electron temperature in eV. ENEPAR(,2) is the strength of the feedback.
    feedback

Recommended when drifts are enabled

Neoclassical theory

Coupling with other codes

Special

Deprecated


  • 6: prescribe the total electron energy flux for a constant electron temperature, ENEPAR(,1) specifies the energy flux in W (no longer supported, use types [16] or [17] instead)
    _deprec

Not yet implemented


  • 7: prescribe the electron temperature profile from the bv_te.dat file (requires b2mndr_boundary_sources.eq.1)
    _future

  • 11: not used
    _future

  • 18: fractional drop condition. Not yet working.
    _future
All
No condition
1
Constant value, gradient
3
Sheath conditions
4
Flux based
3
Decay length
2
Leakage conditions
2
Feedback for const value
5
Recommended when drifts are enabled Neoclassical theory Coupling with other codes Special Deprecated
1
Not yet implemented
2

BCENI

Specifying the type of ion energy or temperature boundary condition for each segment; makes use of ENIPAR to specify additional information, as indicated

No condition


  • 0: default, no boundary condition is applied
    default

Constant value, gradient


  • 1: prescribe the value of the ion temperature, ENIPAR(,1) specifies the temperature in eV
    const

  • 2: prescribe the gradient of the ion temperature, ENIPAR(,1) specifies the temperature gradient in eV.m-1
    const

  • 4: prescribe the value of the ion temperature, weakly a mixed boundary condition, ENIPAR(,1) specifies the temperature in eV and ENIPAR(,2) specifies the 'strength' of the boundary condition
    const

Sheath conditions


  • 3: sheath conditions, ion energy transmission, ENIPAR(,1) specifies the contribution to the energy transmission coefficient [the sound speed used depends on settings of MOMPAR(,ISMAIN,2)]
    sheath

  • 11: sheath conditions, ion energy transmission coefficient, ENIPAR(,1) specifies an energy transmission factor, deltai in Qi = deltai Ti suma na Cs,a
    sheath

  • 12: sheath conditions, ion energy transmission coefficient, ENIPAR(,1) specifies an energy transmission factor, deltai in Qi = deltai Ti suma Γa
    sheath

  • 15: sheath boundary condition, from b2stbc_spb, recommended when using drifts (see Section C.7.5 of manual for details). Linked to using BCCON=14 and BCMOM=13 for all ion species, along with BCENE=15 and BCPOT=11.
    sheath
    drifts

Flux based


  • 5: prescribe the ion energy flux per unit area, ENIPAR(,1) specifies the energy flux density in W.m-2
    flux

  • 8: prescribe the total ion heat flux with constant flux density, ENIPAR(,1) specifies the energy flux in W
    flux

  • 13: prescribe the ion energy flux per unit area proportional to temperature, ENIPAR(,1) specifies the energy flux density per temperature in W.m-2.J-1 (the temperature here in J)
    flux

Decay length


  • 9: prescribe the decay length for the ion temperature, ENIPAR(,1) specifies the decay length in m (can also use type [19] instead)
    decay_len

  • 19: same as [9] but to be used when simultaneously setting BCCON=1 on the same boundary.
    decay_len

Leakage conditions


  • 14: leakage option for ion energy, ENIPAR(,1) specifies the leakage factor, α in Γloss = α CsTi
    leakage

  • 22: radial leakage condition for the ion temperature. ENIPAR(,1) specifies the leakage velocity in units of the collective ion thermal velocity. A temperature gradient such that the diffusive flux is set to match this leakage is imposed.
    leakage

Feedback for const value


  • 10: feedback option for core, ENIPAR(,1) not used, derived from cbshi(0,ISMAIN,coreregno)
    feedback

  • 16: feedback boundary condition with constant temperature, ENIPAR(,1) specifies the power flux in W across the flux surface with index 'b2stbc_type16_ref' (default=-1), ENIPAR(,2) should be something like 0.1 and specifies the strength of the feedback. Also see type [17] below. Available if bceni_16_style=0 (default). If bceni_16_style=1, integrated ion heat flux with constant ion temperature, summed over all core boundaries with BCENI=16. ENIPAR(,1) specifies the power flux in W
    feedback

  • 17: feedback boundary condition with constant shared temperature for both electrons and ions, see BCENE=17 above for description.
    feedback

  • 20: feedback boundary condition with constant temperature, as per type [16] but with 'type20_' switches and a different feedback scheme.
    feedback

  • 25: constant temperature feedback scaled by temperature on the ring bc_type21_ref away. ENIPAR(,1) specifies the desired ion temperature in eV. ENIPAR(,2) is the strength of the feedback
    feedback

Recommended when drifts are enabled

Neoclassical theory

Coupling with other codes

Special

Deprecated


  • 6: prescribe the total ion energy flux for a constant ion temperature, ENIPAR(,1) specifies the energy flux in W (no longer supported, use types [16] or [17] instead)
    _deprec

Not yet implemented


  • 7: prescribe the ion temperature profile from the bv_ti.dat file (requires b2mndr_boundary_sources.eq.1)
    _future

  • 18: fractional drop condition. Not yet working.
    _future
All
No condition
1
Constant value, gradient
3
Sheath conditions
2
Flux based
2
Decay length
1
Leakage conditions Feedback for const value
2
Recommended when drifts are enabled
2
Neoclassical theory Coupling with other codes Special Deprecated Not yet implemented
3

BCPOT

Specifying the type of electric potential or current boundary condition for each segment; makes use of POTPAR to specify additional information, as indicated

No condition


  • 0: default, no boundary condition is applied
    default

Constant value, gradient


  • 1: prescribe the value of the potential, POTPAR(,1) specifies the potential in V
    const

  • 2: prescribe the gradient of the potential, POTPAR(,1) specifies the potential gradient in V.m-1
    const

  • 4: prescribe the value of the potential weakly a mixed boundary condition, POTPAR(,1) specifies the potential in V and POTPAR(,2) specifies the 'strength' of the boundary condition
    const

Sheath conditions


  • 3: sheath conditions, POTPAR(,2) used for biasing [see code for details]
    sheath

  • 11: sheath conditions, electron energy transmission from b2stbc_spb, POTPAR(,2) specifies the bias potential in V. Recommended for use in cases with drifts, along with BCENE/I=15, BCCON=14, and BCMOM=13.
    sheath
    drifts

Flux based


  • 5: prescribe the current flux density per unit area, POTPAR(,1) specifies the electric current flux density in A.m-2
    flux

  • 8: prescribe the total electric current with constant flux density, POTPAR(,1) specifies the electric current in A
    flux

Decay length


  • 9: prescribe the decay length for the potential, POTPAR(,1) specifies the decay length in m
    decay_len

Leakage conditions

Feedback for const value


  • 16: Constant electric potential feedback on imposed total current. The current prescribed is given by the sum of the POTPAR(IB,1) (in A) over all the BCPOT=16 boundaries. Still experimental, will not work for drift cases.
    feedback

  • 21: constant potential feedback scaled by potential on the ring 'bc_type21_ref' away. POTPAR(,,1) specifies the desired potential in V. POTPAR(,,2) is the strength of the feedback
    feedback

Recommended when drifts are enabled


  • 12: Imposes the currents due to drifts for the South core boundary. Must be used in conjunction with istyle_cur_contr_on_S_and_N.eq.2
    drifts

  • 13: Imposes the currents due to drifts for the South private flux and North boundaries. Must be used in conjunction with istyle_cur_contr_on_S_and_N.eq.2
    drifts

Neoclassical theory

Coupling with other codes

Special

Deprecated

Not yet implemented


  • 6: prescribe the total current flux density for a constant potential [not yet available]
    _future

  • 7: prescribe the given profile of potential from the bv_po.dat file (requires b2mndr_boundary_sources.eq.1)
    _future

  • 10: feedback option for core [not yet tested!!!!!!!!!] (based on using cbsch(0,coreregno))
    _future
All
No condition
1
Constant value, gradient
4
Sheath conditions
1
Flux based
4
Decay length
1
Leakage conditions
2
Feedback for const value
5
Recommended when drifts are enabled Neoclassical theory Coupling with other codes
3
Special Deprecated Not yet implemented
1

BCCON

Specifying the type of density boundary condition for each segment and species (fastest varying index is species); makes use of CONPAR to specify additional information, as indicated:

No condition


  • 0: default, no boundary condition is applied
    default

Constant value, gradient


  • 1: prescribe the value of the density, CONPAR(,,1) specifies the required density in m-3
    const

  • 2: prescribe the gradient of the density, CONPAR(,,1) specifies the required density gradient in m-4
    const

  • 4: prescribe the value of the density, weakly a mixed boundary condition, CONPAR(,,1) specifies the required density in m-3 and CONPAR(,,2) specifies the 'strength' of the boundary condition
    const

  • 21: prescribe the value of the density and add a poloidal density variation to get a solution which is as close as possible to neoclassical theory. It is recommended to use this boundary condition together with corresponding condition on ion temperature (BCENI=24). The total desired density is summed over all BCCON=21 core boundaries. CONPAR(,,1) specifies the desired density in m-3.
    const
    neoclassical

Sheath conditions


  • 3: sheath conditions, CONPAR(,,1) not used (zero gradient is used)
    sheath

Flux based


  • 5: prescribe the particle flux per unit area, CONPAR(,,1) specifies the required particle flux density in m-2.s-1
    flux

  • 6: prescribe the total particle flux for a constant density, CONPAR(,,1) specifies the particle flux in s-1
    flux

  • 8: prescribe the total particle flux with constant flux density, CONPAR(,,1) specifies the particle flux in s-1
    flux

  • 14: sound speed velocity flux, CONPAR(,,1) is a multiplier to the outgoing sound speed Cs. To be used in conjunction with BCENE/I=15, BCPOT=11, and BCMOM=13. Recommended for cases with drifts.
    flux
    drifts

Decay length


  • 9: prescribe the decay length for the density, CONPAR(,,1) specifies the gradient length in metres (should use type 15 instead when drifts are turned on)
    decay_len

Leakage conditions


  • 10: leakage option for density, recommended for cases with drifts, CONPAR(,,1) specifies the leakage factor, α in Γloss = α Cs na. CONPAR(,,2) is an optional stabilization parameter that can be set to a positive value to help with the linearization of the boundary condition.
    leakage
    drifts

  • 15: prescribe a radial leakage velocity, CONPAR(,,1) specifies the leakage velocity in units of the local thermal velocity.
    leakage

Feedback for const value


  • 11: particle flux feedback boundary condition, CONPAR(,,1) not used, derived from CBSNA(0,IS,IREG). For feedback schemes not specified via b2.feedback_control.parameters, the species used must be declared using the 'b2stbc_isfeedback' switch.
    feedback

  • 12: particle density feedback boundary condition, as above, CONPAR(,,1) not used, derived from CBSNA(0,IS,IREG). The species used must be declared using the 'b2stbc_isfeedback' switch.
    feedback

  • 13: particle density to achieve specified total flux, CONPAR(,,1) is the specified flux crossing the flux surface 'b2stbc_type13_ref' steps away from the boundary, CONPAR(,,2) is the strength of the feedback, CONPAR(,,3), when running with Eirene and the 'ionising core' switch is used, is set internally to match the re-entering flux of ionised neutrals that crossed the core boundary (one must then have 'ionising_core'.eq.-IB where IB is the boundary index). The feedback scheme can be further tweaked with the switches 'b2stbc_type13_norm' and 'b2stbc_type13_fac'. See code for details.
    feedback

  • 20: constant density feedback condition, CONPAR(,,1) specifies the desired density in m-3.
    feedback

  • 24: constant density feedback scaled by density on the ring 'bc_type21_ref' away. CONPAR(,,1) specifies the desired density in m-3. CONPAR(,,2) is the strength of the feedback
    feedback

Recommended when drifts are enabled

Neoclassical theory

Coupling with other codes


  • 16: particle density to achieve specified total flux, used with ASTRA coupling. The total desired flux is summed over all BCCON=16 core boundaries. CONPAR(,,1) specifies the desired particle flux in s-1.
    coupling
    flux

  • 18: prescribe total main ion particle flux, used with ASTRA coupling.
    coupling
    const

  • 19: particle flux feedback boundary condition, flux is summed over neutrals and ions, for coupling with ASTRA. The total desired flux is summed over all BCCON=19 core boundaries. This boundary condition type is applied to ions in their highest ionisation stage. CONPAR(,,1) specifies the desired particle flux in s-1.
    coupling
    feedback

Special

Deprecated

Not yet implemented


  • 7: prescribe the given profile of density from the bv_na.dat file (requires b2mndr_boundary_sources.eq.1)
    _future
All
No condition
1
Constant value, gradient
6
Sheath conditions
2
Flux based
2
Decay length
1
Leakage conditions
1
Feedback for const value Recommended when drifts are enabled Neoclassical theory Coupling with other codes Special
2
Deprecated Not yet implemented
2

BCMOM

Specifying the type of parallel momentum or velocity boundary condition for each segment and species (fastest varying index is species); makes use of MOMPAR to specify additional information, as indicated

No condition


  • 0: default, no boundary condition is applied
    default

Constant value, gradient


  • 1: prescribe the value of the parallel velocity, MOMPAR(,,1) specifies the parallel velocity in m.s-1
    const

  • 2: prescribe the gradient of the parallel velocity, MOMPAR(,,1) specifies the parallel velocity gradient in s-1
    const

  • 4: prescribe the value of the velocity, weakly a mixed boundary condition, MOMPAR(,,1) specifies the parallel velocity in m.s-1 and MOMPAR(,,2) specifies the 'strength' of the boundary condition
    const

  • 12: condition from b2stbc_spb for the parallel momentum
    const

  • 14: condition from b2stbc_spb for the parallel momentum
    const

  • 15: prescribe the value of the parallel velocity, scaled with B_average/B_local
    const

Sheath conditions


  • 3: sheath conditions, Mach number as input, if MOMPAR(,,2) < 0.5, then the velocity is set to exactly MOMPAR(,,1) * Cs,collective, otherwise the velocity is set to be at least MOMPAR(,,1) * Cs,a, the thermal velocity of that species
    sheath

  • 13: sheath boundary condition from b2stbc_spb for the parallel momentum. To be used in conjunction with BCENE/I=15, BCPOT=11, and BCCON=14. Recommended for cases with drifts.
    sheath

Flux based


  • 5: prescribe the parallel momentum flux per unit area, MOMPAR(,,1) specifies the parallel momentum flux density in N.m-2
    flux

  • 9: prescribe the total parallel momentum flux with constant flux density, MOMPAR(,,1) specifies the parallel momentum flux in N
    flux

Decay length


  • 10: prescribe the decay length for the parallel momentum, MOMPAR(,,1) specifies the decay length in m
    decay_len

Leakage conditions


  • 17: leakage option for parallel momentum, MOMPAR(,,1) specifies the leakage factor, α in Γloss = α Cs,a ma na ua
    leakage

Feedback for const value

Recommended when drifts are enabled

Neoclassical theory

Coupling with other codes

Special


  • 8: special : limited shear, imposes zero gradient for the Mach number. [[[Eventually intended to have MOMPAR(,,1) specify the gradient of the Mach number in m-1]]]
    special

  • 11: Rozhansky viscosity condition for the parallel momentum, MOMPAR(,,1) is not used
    special

Deprecated

Not yet implemented


  • 6: prescribe the total parallel momentum flux for a constant parallel velocity [not yet available]
    _future

  • 7: prescribe the given profile of parallel velocity from the bv_ua.dat file (requires b2mndr_boundary_sources.eq.1)
    _future