SuperFINIX Cerberus input/output manual

SuperFINIX may take input and give output variables and fields from or to Cerberus. Some input variables are shared with the SuperFINIX input file.

Level index in field names

Some input and output fields can be specified on different levels of the calculation geometry. Level 1 refers to the top level defined using set toplattice option in the input file. If the top lattice contains other lattices, fields at level 2 are available and so on. As an example, the geometry can consist of multiple fuel assemblies each containing multiple fuel rods. On level 1 the fields are specified on assembly level and on level 2 on rod level.

Input variables

Variable name	Number of values	Description
sf_iv_finix_bc_type	1	Boundary condition type for the fuel rods. 0 = user specified cladding outer surface temperature, 2 = user specified heat transfer coefficient and coolant bulk temperature.

Input fields

Field name	Number of values	Description
sf_if_power_lvl<idx>	Mesh size at level <idx>	Power deposited in the fuel (W).
sf_if_clad_T_lvl<idx>	Mesh size at level <idx>	Cladding outer surface temperature (K).
sf_if_HTC_lvl<idx>	Mesh size at level <idx>	Heat transfer coefficient between cladding outer surface and coolant (W/(m2K)).
sf_if_cool_T_lvl<idx>	Mesh size at level <idx>	Coolant bulk temperature (K).
sf_if_power_radial	Mesh size at radial input level	Power deposited in the fuel (W).
sf_if_rod_idx	Horizontal mesh size at level where rods are located (<idx>)	Index of rod to initialize to each position. Used with fuel shuffling.

Output variables

There are no output variables in the current version.

Output fields

Field name	Number of values	Description
sf_of_vol_ave_fuel_T_lvl<idx>	Mesh size at level <idx>	Volume averaged fuel temperature (K)
sf_of_eff_fuel_T_lvl<idx>	Mesh size at level <idx>	Effective 0.7/0.3 Doppler fuel temperature (K)
sf_of_max_fuel_T_lvl<idx>	Mesh size at level <idx>	Maximum fuel temperature (K)
sf_of_vol_ave_fuel_T_radial	Mesh size at radial output level	Volume averaged fuel temperature (K)
sf_of_rod_idx	Horizontal mesh size at the geometry level where rods are located	Current rod index at each position. Used with fuel shuffling.
sf_of_centerline_fuel_T	Mesh size at level where rods are located	Centerline fuel temperature (K)
sf_of_outer_fuel_T	Mesh size at level where rods are located	Pellet surface temperature (K)
sf_of_inner_clad_T	Mesh size at level where rods are located	Cladding inner surface temperature (K)
sf_of_outer_clad_T	Mesh size at level where rods are located	Cladding outer surface temperature (K)
sf_of_gap_width	Mesh size at level where rods are located	Width of the gas gap between fuel pellet and cladding (m)
sf_of_gap_conductance	Mesh size at level where rods are located	Gas gap conductance between fuel pellet and cladding (W/(m2K))
sf_of_centerline_burnup	Mesh size at level where rods are located	Pellet centerline burnup (MWd/kgU)
sf_of_outer_clad_radius	Mesh size at level where rods are located	Cladding outer radius (m)
sf_of_power_to_coolant	Mesh size at level where rods are located	Power transferred to coolant (W) calculated as $rod\_mult \cdot 2\pi r h \cdot htc \cdot (T_{\text{clad}} - T_{\text{cool}})$. Should be used only if the heat transfer coefficients and bulk coolant temperatures have been given to SuperFINIX.
sf_of_outer_clad_heat_flux_steady	Mesh size at level where rods are located	Power deposited in the fuel converted to heat flux ((W/(m2) by dividing the power with the outer surface area of the cladding.