Rooster

Robust Object Oriented Solver of Transport Equations in a Reactor

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Code architecture
Input description

Ongoing projects
Open projects

The input file should have name input. It consists of lines (cards) identified by keywords. The card are presented below by examples in alphabetical order of the keywords. All numerical values and upper-case words are specified by users. The low-case words are keywords and should not be changed. The colour code indicates the class to which the card "belongs": Control, Fluid, Core and Solid.

# : Comment

# A line started with a hash mark is considered a comment.

& : Line continuation

# An ampersand symbol at the end of the line &
 is a line continuation symbol.

betaeff : Effective fractions of delayed neutrons

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Beta-effective in 6 time groups
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

betaeff   0.000285  0.0015975 0.00141   0.0030525 0.00096   0.000195  # a comment can also be put here

Number of values (i.e. number of the time groups) should be the same as in card dnplmb.

clad : Cladding tube

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Cladding tube
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     id        matid     ri(m)     ro(m)     nr

clad      C01       SS1       4.1e-3    4.5e-3    3

id : user-defined cladding tube id;

matid : user-defined cladding tube material id (should appear in the mat card);

ri : inner radius of cladding tube (m);

ro : outer radius of cladding tube (m);

nr : number of radial nodes.

coregeom : Core geometry

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Core geometry
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     geometry  pitch(m)  botBC     topBC

coregeom  hex06     0.18018   0         0

geometry : flag of core geometry:

square: square geometry;

hex01: hexagonal geometry with 1 node per hexagon;

hex06: hexagonal geometry with 6 node per hexagon;

hex24: hexagonal geometry with 24 node per hexagon.

pitch : distance between centers of nodes in plane (m);

botBC : flag of bottom boundary conditions:

0: vacuum boundary condition

1: reflective boundary condition

topBC : flag of top boundary conditions:

0: vacuum boundary condition

1: reflective boundary condition

coremap : Core map

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Core map
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

coremap  0     0     0     0     0     0     0     0     0      #1

coremap     0     0    SHI   SHI   SHI   SHI    0     0     0   #2

coremap  0     0    SHI   BLA   BLA   BLA   SHI    0     0      #3

coremap     0    SHI   BLA   FIS   FIS   BLA   SHI    0     0   #4

coremap  0    SHI   BLA   FIS   FIS   FIS   BLA   SHI    0      #5

coremap     0    SHI   BLA   FIS   FIS   BLA   SHI    0     0   #6

coremap  0     0    SHI   BLA   BLA   BLA   SHI    0     0      #7

coremap     0     0    SHI   SHI   SHI   SHI    0     0     0   #8

coremap  0     0     0     0     0     0     0     0     0      #9

The coremap card defined one row of assemblies in the core and consists of either boundary condition flag (0: vaccuum; 1: reflective) or of a stack id (should appear in the stack card).

dnplmb : Delayed neutron precursor decay time constants

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Delayed neutron precursor decay time constants in 6 time groups (1/s)
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

dnplmb    0.0127    0.0317    0.115     0.311     1.4       3.87

Number of values (i.e. number of the time groups) should be the same as in card betaeff.

fuel : Fuel column

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Fuel column
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     id        matid     ri(m)     ro(m)     nr

fuel      F01       MOX1      1e-3      4e-3      20

id : user-defined fuel column id;

matid : user-defined fuel column material id (should appear in the mat card);

ri : inner radius of fuel column (m);

ro : outer radius of fuel column (m);

nr : number of radial nodes.

fuelrod : Fuel rod axial levels

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Fuel rod axial levels
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     id        fuelid    hgap      cladid    p2d       mltpl     pipeid    pipenodeid

fuelrod   FR01      F01       0         C01       1.02      10        UP1       2

fuelrod   FR01      F01       0         C01       1.02      10        UP1       3

fuelrod   FR01      F01       0         C01       1.02      10        UP1       4

fuelrod   FR01      F01       0         C01       1.02      10        UP1       5

fuelrod   FR02      F01       1000      C01       1.02      10        UP2       2

fuelrod   FR02      F01       1000      C01       1.02      10        UP2       3

fuelrod   FR02      F01       1000      C01       1.02      10        UP2       4

fuelrod   FR02      F01       1000      C01       1.02      10        UP2       5

id : user-defined id of fuel rod to which the axial layer belongs;

fuelid : fuel column id defined in fuel card;

hgap : fuel-clad gap conductance (W/m²K); if zero, the gap conductance is calculated by the code;

cladid : clad tube id defined in clad card;

p2d : pitch-to-diameter ratio of the fuel rod lattice;

mltpl : multiplicity of the heat exchange surface (actual number of fuel rods simulated by one).

pipeid : thermal-hydraulic pipe id defined in the pipe card;

pipenodeid : index of the node inside the thermal-hydraulic pipe coupled to the current fuel rod level.

innergas : Fuel rod inner gas

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Fuel rod inner gas
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     fuelrodid matid     plenv(m3)

innergas  FR01      HE1       53e-6

innergas  FR02      HE1       53e-6

fuelrodid : id of fuel rod the inner gas belongs to;

matid : user-defined inner gas material id (should appear in the mat card);

plenv : volume of the gas plenum (m³);

jun : Dependent junction

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Dependent junction
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     from      to

jun       UP1       PLN

jun       DOWN      UP2

jun       UP2       PLN

A junction connects two pipes:

from : id of the user-defined pipe id the junction comes from;

to : id of the user-defined pipe id the junction comes to.

The mass flowrate in the dependent junction could be found from mass flowrates in independent juntions.

jun-i : Independent junction

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Inependent junction
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     from      to

jun-i     PLN       DOWN

A junction connects two pipes:

from : id of the user-defined pipe id the junction comes from;

to : id of the user-defined pipe id the junction comes to.

The mass flowrate in the dependent junction could be found from mass flowrates in independent juntions which found by integration of the momentum conservation equations.

jun-i-f : Independent junction with user-defined flowrate

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Inependent junction with user-defined flowrate
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     from      to        signal

jun-i-f   DOWN      UP1       MDOT_VS_T

A junction connects two pipes:

from : id of the user-defined pipe id the junction comes from;

to : id of the user-defined pipe id the junction comes to.

signal : id of the user-defined signal of flowrate in the junction.

The mass flowrate in the dependent junction could be found from mass flowrates in independent juntions which found by integration of the momentum conservation equations. In case of the independent junction with user-defined flowrate, the time derivative of mass flowrate is set to zero and flowrate is set equal to the specified signal at the current time step.

jun-i-p : Independent junction with user-defined pump head

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Inependent junction with user-defined pump head
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     from      to        signal

jun-i-p   PLN       DOWN      PMPHEAD_VS_T

A junction connects two pipes:

from : id of the user-defined pipe id the junction comes from;

to : id of the user-defined pipe id the junction comes to.

signal : id of the user-defined signal of pump head in the junction.

The mass flowrate in the dependent junction could be found from mass flowrates in independent juntions which found by integration of the momentum conservation equations. In case of the independent junction with user-defined pump head, the specifieed signal at the current time step is added to the right-hand side of the momentum conservation equation.

lookup : Lookup table control block

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Lookup table: pump head in junction vs time
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     insignal  outsignal

lookup    TIME      PMPHEAD_VS_T &

          0.0       0 &

          10.0      1e5

#
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Lookup table: flowrate in junction vs time
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     insignal  outsignal

lookup    TIME      MDOT_VS_T &

          0.0       0 &

          10.0      10

#
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Lookup table: temperature in pipe node vs time
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     insignal  outsignal

lookup    TIME      TEMP_VS_T &

          0.0       0 &

          10.0      700

The control block is specified by a list of pairs starting with:

insignal : id of the input signal x which is either defined in the signal card or the output signal of another control block and

outsignal : id of the output signal y

and followed by N pairs of numerical values x(i) and y(i) to approximate a function y = f(x). At every time step an output signal y is linearly interpolated for current value of the input signal x.

mat : Material

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Materials
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     id        type      p0(Pa)    temp0(K)

mat       NA        na        1e5       673

#####     id        type      pu(-)     b(MWD/kg) x(-)      por(-)    temp0(K)

mat       MOX1      mox       0.15      0         0.02      0.05      673

#####     id        type      temp0(K)

mat       SS1       ss316     673

#####     id        type      p0(Pa)    temp0(K)

mat       HE1       he        1e6       673

id : user-defined material id;

type : material id

The other values depend on the material type. The following materials are available in the coolant properties database:

he : helium as an inner gas material of fuel rods;

p0 : initial pressure (Pa)

temp0 : initial temperature (K)

mox : mixed U-Pu oxide as a fuel material of fuel rods;

pu : plutonium content (-)

b : burnup (MWd/kgHM)

x : deviation from stoichiometry (-)

por : porosity (-)

temp0 : initial temperature (K)

na : sodium as a coolant;

p0 : initial pressure (Pa)

temp0 : initial temperature (K)

ss316 : stainless steel 316 as a cladding material of fuel rods;

temp0 : initial temperature (K)

mix : Homogeneous mix of isotopes

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Mix: fuel in inner zone
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     id        isoid     numdens             sigtemp

mix       INNER     U235j311  3.58838E-05         TEMP

mix       INNER     U238j311  7.05072E-03         TEMP

mix       INNER     Pu238j311 6.31883E-06         TEMP

mix       INNER     Pu239j311 8.71553E-04         TEMP

mix       INNER     Pu240j311 2.59858E-04         TEMP

mix       INNER     Pu241j311 6.98635E-05         TEMP

mix       INNER     Pu242j311 2.42475E-05         TEMP

mix       INNER     Am241j311 1.70991E-05         TEMP

mix       INNER     O16j311   1.65043E-02         TEMP

mix       INNER     C0j311    4.75629E-05         TEMP

mix       INNER     Si28j311  2.25772E-04         TEMP

mix       INNER     Si29j311  1.10737E-05         TEMP

mix       INNER     Si30j311  7.06525E-06         TEMP

mix       INNER     P31j311   1.10562E-05         TEMP

mix       INNER     Ti46j311  8.19752E-06         TEMP

mix       INNER     Ti47j311  7.23535E-06         TEMP

mix       INNER     Ti48j311  7.02030E-05         TEMP

mix       INNER     Ti49j311  5.04663E-06         TEMP

mix       INNER     Ti50j311  4.73566E-06         TEMP

mix       INNER     Cr50j311  1.58887E-04         TEMP

mix       INNER     Cr52j311  2.94632E-03         TEMP

mix       INNER     Cr53j311  3.27778E-04         TEMP

mix       INNER     Cr54j311  8.00808E-05         TEMP

mix       INNER     Mn55j311  3.53226E-04         TEMP

mix       INNER     Fe54j311  8.00560E-04         TEMP

mix       INNER     Fe56j311  1.21188E-02         TEMP

mix       INNER     Fe57j311  2.74958E-04         TEMP

mix       INNER     Fe58j311  3.59615E-05         TEMP

mix       INNER     Ni58j311  1.87786E-03         TEMP

mix       INNER     Ni60j311  6.99261E-04         TEMP

mix       INNER     Ni61j311  2.98974E-05         TEMP

mix       INNER     Ni62j311  9.37938E-05         TEMP

mix       INNER     Ni64j311  2.31362E-05         TEMP

mix       INNER     Mo92j311  4.51168E-05         TEMP

mix       INNER     Mo94j311  2.78070E-05         TEMP

mix       INNER     Mo95j311  4.76300E-05         TEMP

mix       INNER     Mo96j311  4.96037E-05         TEMP

mix       INNER     Mo97j311  2.82709E-05         TEMP

mix       INNER     Mo98j311  7.10924E-05         TEMP

mix       INNER     Mo100j311 2.80498E-05         TEMP

mix       INNER     Na23j311  7.63797E-03         TEMP

mix       INNER     He4j311   6.11441E-07         TEMP

id: user-defined id of the mix;

isoid: id of the isotope; the GENDF file with this name should exist in nulcera data directory nddir;

numdens: number density of the isotope isoid in the mix id (barn^-1cm^-1);

sigtemp: signal defining the temperature in K of the isotope isoid in the mix id.

nddir : Nuclear data directory

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Nuclear data directory
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

nddir     DATA25

nddir: path to directory containing multigroup cross-section files in GENDF format.

pipe : Pipe without free level

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Pipes
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     id        matid     dhyd(m)   len(m)    dir(-)    areaz(m2) nnodes

pipe      UP1       NA        0.01      1.0       1.0       1.1       10

id : user-defined pipe id;

matid : user-defined material id (should appear in the mat card);

dhyd : hydraulic diameter (m);

len : pipe length (m);

dir : pipe direction: from -1.0 (downward) up to 1.0 (upward) (-);

areaz : flow area (m²);

nnodes : number of nodes.

pipe-f : Pipe with free level

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Pipe with free level
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     id        matid     dhyd(m)   len(m)    areaz(m2)

pipe-f    PLN       NA        0.1       1.0       1.1

id : user-defined pipe id;

matid : user-defined material id (should appear in the mat card);

dhyd : hydraulic diameter (m);

len : pipe length (m);

areaz : flow area (m²).

A pipe with free level has always one node.

pipe-t : Pipe without free level with temperature defined by signal

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Pipe with user-defined temperature
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     id        matid     dhyd(m)   len(m)    dir(-)    areaz(m2) nnodes    signal

pipe-t    DOWN      NA        0.01      1.0       -1.0      1.1       10        TEMP_VS_T

id : user-defined pipe id;

matid : user-defined material id (should appear in the mat card);

dhyd : hydraulic diameter (m);

len : pipe length (m);

dir : pipe direction: from -1.0 (downward) up to 1.0 (upward) (-);

areaz : flow area (m²);

nnodes : number of nodes;

signal : id of the signal specifying temperature in all nodes of the pipe.

The time derivative of temperature in every node of the pipe is set to zero and temperature is set equal to the specified signal at the current time step.

power0 : Initial reactor power

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Initial reactor power
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

power0    2990.e6

power0: initial reactor power (W).

signal : User-defined signal

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Signals
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     id        value

signal    TIME      time

signal    PI        3.14159

signal    TEMP      600.

id: user-defined signal id;

type: signal value.

Currently available signals (under development):

3.14159: any constant numeric value;

time: time of the problem(s).

solve : Model activation flag

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Model activation flags
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     model

solve     fgrain

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     model

solve     fluid

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     model

solve     fuelrod

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     model

solve     pointkinetics

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     model               ng

solve     spatialkinetics     25

model: keyword of the model to be solved:

fgrain: fission gas behaviour model (under development);

fluid : thermal-hydraulic model;

fuelrod : fuel rod behaviour model (fluid should be activated);

pointkinetics : point reactor kinetics model;

spatialkinetics : spatial reactor kinetics model;

ng : number of energy groups.

Note that even if the respective cards are present in the input file, the task will not be solved unless activated by the solve card.

stack : Vertical stack of homogeneous mixes

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Stack of mixes: fissile subassembly of inner zone
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     id        mixid     pipeid    pipenodeid

stack     FIN       PLUG1     UP01      1

stack     FIN       GASPLE1   UP02      1

stack     FIN       GASPLE1   UP02      2

stack     FIN       GASPLE1   UP02      3

stack     FIN       GASPLE1   UP02      4

stack     FIN       GASPLE1   UP02      5

stack     FIN       GASPLE1   UP02      6

stack     FIN       GASPLE1   UP02      7

stack     FIN       GASPLE1   UP02      8

stack     FIN       GASPLE1   UP03      1

stack     FIN       GASPLE1   UP04      1

stack     FIN       SUPPOR1   UP05      1

stack     FIN       AXBLA     UP06      1

stack     FIN       AXBLA     UP06      2

stack     FIN       AXBLA     UP06      3

stack     FIN       AXBLA     UP06      4

stack     FIN       AXBLA     UP06      5

stack     FIN       AXBLA     UP06      6

stack     FIN       INNER     UP07      1

stack     FIN       INNER     UP07      2

stack     FIN       INNER     UP07      3

stack     FIN       INNER     UP07      4

stack     FIN       INNER     UP07      5

stack     FIN       INNER     UP07      6

stack     FIN       INNER     UP07      7

stack     FIN       INNER     UP07      8

stack     FIN       INNER     UP07      9

stack     FIN       INNER     UP07      10

stack     FIN       INNER     UP07      11

stack     FIN       INNER     UP07      12

stack     FIN       INNER     UP07      13

stack     FIN       INNER     UP07      14

stack     FIN       INNER     UP07      15

stack     FIN       INNER     UP07      16

stack     FIN       INNER     UP07      17

stack     FIN       INNER     UP07      18

stack     FIN       INNER     UP07      19

stack     FIN       INNER     UP07      20

stack     FIN       AXBLA     UP08      1

stack     FIN       AXBLA     UP08      2

stack     FIN       AXBLA     UP08      4

stack     FIN       AXBLA     UP08      5

stack     FIN       AXBLA     UP08      6

stack     FIN       AXBLA     UP08      3

stack     FIN       GASPLE1   UP09      1

stack     FIN       GASPLE1   UP09      2

stack     FIN       PLUG1     UP10      1

stack     FIN       EMPTY     UP11      1

stack     FIN       EMPTY     UP11      2

stack     FIN       EMPTY     UP11      3

stack     FIN       OUTLET    UP12      1

stack     FIN       OUTLET    UP12      2

stack     FIN       OUTLET    UP12      3

stack     FIN       OUTLET    UP12      4

stack     FIN       OUTLET    UP12      5

stack     FIN       OUTLET    UP12      6

stack     FIN       OUTLET    UP12      7

stack     FIN       OUTLET    UP12      8

stack     FIN       OUTLET    UP12      9

stack     FIN       OUTLET    UP12      10

id: user-defined id of the vertical stack of homogeneous mixes;

mixid: user-defined id of the homogeneous mix of isotopes filling the node if the stack id (should appear in the mix card);

pipeid: user-defined id of the pipe (should appear in the pipe card);

pipenodeid: id of the node number of the pipe pipeid defining the node of the stack id.

Note: the stack represents a subassembly of the core. The axial nodalization of the stack is defined by linking every node of the stack with a pipe node.

t0 : Initial time

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Initial time
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     tinit

t0        0.0

tinit: integration starting time (s).

t_dt : Integration time set

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Integration time set
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     tend(s)   dt(s)

t_dt      100       1

t_dt      1000      10

tend: end of integration time interval (s);

dt: output time step for the current integration interval (s).

The given example specifies two integration time intervals: 1) from t0 to 100 s with output at every second and 2) from 100 s to 1000 s with output every 10 s.

tlife : Prompt neutron lifetime

#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----
# Prompt neutron lifetime
#---- ----1---- ----2---- ----3---- ----4---- ----5---- ----6---- ----7---- ----8---- ----9---- ----0----

#####     tlife(s)

tlife     0.0005

tlife: prompt neutron lifetime (s).

Code supervisor:
Dr. Konstantin Mikityuk
Paul Scherrer Institute
Switzerland