2. Input file
The input file of NECP-X is introduced. Comments are supported in the input file. All characters following an exclamation mark ! are commentary and are ignored by NECP-X. All strings in input card are case insensitive. Five levels are designed to fully describe a NECP-X model: Block, card, subcard and keyword/value pairs. The input file contains four blocks: Material, Geometry, Transient and Options. Transient block is optional and is only needed in transient calculation.
The Material Block consists of 2 required cards. Structure for a sample input of material Block:
Material
library:
! definition body
/library
mat: fuel
! definition body
/mat
/Material
The library card defines the cross section libraries used for a problem, including 6 keywords: library, mg_lib, ce_lib , dep_lib, act_lib , act_mg_lib.
library: <micro | macro>
mg_lib = < default | <path> >
[ce_lib = < default | <path> >]
[dep_lib = < default | <path> >]
[act_lib = < default | <path> >]
[act_mg_lib = < default | <path> >]
/library
library keyword
Specifies macro/micro cross section library to be used.
micro
· String value
· Micro cross section library to be used
macro
· String value
· Macro cross section library to be used, if macro cross section is selected, mg_lib needs to be given by the user.
mg_lib keyword
Required. Specifies the path of the multi-group cross section library
default
· string value
· Only works for micro library. If default is used, NECP-X will find library in ${CMAKE_SOURCE_DIR}/library/necl_mg_endf70_wims69e and ${NECP_X_ROOT}/library/necl_mg_endf70_wims69e in sequence. The first one found by NECP-X will be used.
<path>
· String value
· User specified path of the library to be used.
ce_lib keyword
Optional. Only works for micro library. Specifies the path of the continuous energy cross section library for self-shielding calculation.
default
· String value
· If default is used, NECP-X will find library in ${CMAKE_SOURCE_DIR}/library/necl_ce_endf70 and ${NECP_X_ROOT}/library/necl_ce_endf70 in sequence. the first one found by NECP-X will be used.
<path>
· String value
· User specified path of the library to be used.
dep_lib keyword
Optional. Only works for micro library. Specifies the path of the depletion library for depletion calculation.
default
· String value
· If default is used, NECP-X will find library in ${CMAKE_SOURCE_DIR}/library/pwrb_c1613.dat and ${NECP_X_ROOT}/library/pwrb_c1613.dat in sequence. The first one found by NECP-X will be used.
<path>
· String value
· User specified path of the library to be used.
· depletion libraries available: 1. deplib_233: the compressed deplib with the kappa of serpent included 2. deplib_233_spt: the compressed deplib with the kappa of serpent included 3. deplib_233_endf: the compressed deplib with the kappa of endf/b-vii.0 included
act_lib keyword
Optional. Only works for micro library. Specifies the path of the activation library for activation calculation.
<path>
· String value
· User specified path of the library to be used.
· activation libraries available: 1. deplib_3838: the full-fidelity activation library 2. actlib_353: the compressed activation library
act_mg_lib keyword
Optional. Only works for micro library. Specifies the path of the activation library for activation calculation.
<path>
· String value
· User specified path of the library to be used.
· activation libraries available: 1. jeff31a: the activation xs library based on jeff-3.1/a evaluated library 2. eaf2010: the activation xs library based on eaf-2010 evaluated library
The mat card defines materials compositions, nuclide index and atomic density, including 3 keywords mat, id and density:
mat: <id_mat>
id = <nuclide_id> ; density = <atom_number_density>
[id = <nuclide_id> ; density = <atom_number_density>]
/mat
mat keyword
<id_mat>
· String value
· string name of the material specified by user.
id keyword
<nuclide_id>
· String value
· ID of composite nuclide for the micro library.
· ID of the mixture for the macro library.
density keyword
<atom_number_density>
· Real value. Unit is atoms/barn-cm.
· This will not be used for the macro library, in which case any value can be filled.
The Geometry block consists of 5 required cards. Structure for a sample input of Geometry block:
Geometry
[ Surface:
! definition body
/Surface
]
[ Regions:
! definition body
/Regions
]
Pin_geometry:
! definition body
/Pin_geometry
Pin:
! definition body
/Pin
Lattice_geometry
! definition body
/Lattice_geometry
Assembly_geometry
! definition body
/Assembly_geometry
[ Grid_geometry
! definition body
/Grid_geometry
]
[ Insert_geometry
! definition body
/Insert_geometry
]
[ Control_rod
! definition body
/Control_rod
]
core_geometry
! definition body
/core_geometry
/Geometry
The Surface card is needed when the Regions card is used. It defines the surfaces to describe complex geometry. Supported surfaces are listed below:
Supported CSG surfaces
This card contains multiple surf subcards, and each of the subcards defines multiple surfaces. It is noted that user must define one surface in one line, and each line includes keywords: ID, type and coes.
Surface:
surf:
ID = <int_ID_surf>; type = <surf_type>; coes = <surf_coes(:)>
[ID = <int_ID_surf>; type = <surf_type>; coes = <surf_coes(:)>]
/surf
/Surface
ID keyword
<int_ID_surf>
· Positive integer value.
· Specifies the integer ID of one surface, which will be used in the regions card.
type keyword
<surf_type>
· String value.
· Specifies the geometry type of this surface, all the supported types are listed above.
coes keyword
<surf_coes(:)>
· Array of real value.
· Specifies the coefficients used to define the surface.
The Regions card is needed when the user wants to define complex CSG pin_geom_type rather than simple built-in types. It defines all regions used to construct pin geometry. This card contains multiple region subcards, and each of the subcards includes keywords: region, defID, surfs, point, radii, n_angle, angles, n_x, n_y, x and y.
Regions:
region: <id_region>
defID = <int_id_region>
surfs = <int_id_surfs(:)>
[point = <coordinates(:)>]
[radii = <radii(:)>]
[n_angle = <n_angle>]
[angles = <angles(:)>]
[n_x = <n_x_mesh>]
[n_y = <n_y_mesh>]
[x = <x_meshs(:)>]
[y = <y_meshs(:)>]
/region
/Regions
region keyword
<id_region>
· String value.
· Specifies the string ID of one region.
defID keyword
<int_id_region>
· Positive integer value.
· Specifies the integer ID of one region, which will be used in the pin geometry block.
surfs keyword
<int_id_surfs(:)>
· Array of signed integer value.
· Specifies the signed surfaces that bound the region. Each of the value represents a surface defined by surf subcard. And now the code only support intersection boolean operator for surfaces by default.
point keyword
<coordinates(:)>
· Two real values.
· Specifies the coordinates(x and y) of the center point used in mesh division.
radii keyword
<radii(:)>
· Array of positive real. Unit is cm, size > 0, the values should be monotonically increasing.
· Specifies the radii of concentric cylinder, the center of which is defined by point.
n_angle keyword
<n_angle>
· Positive integer.
· Specifies number of azimuthal meshes of this region, the center of which is defined by point.
angles keyword
<angles(:)>
· Array of positive real.
· Specifies the angles of azimuthal meshes. Both using angles and n_angle are not allowed.
n_x keyword
<n_x_mesh>
· Positive integer value.
· The number of equally spaced flat source region grids in x direction.
n_y keyword
<n_y_mesh>
· Positive integer value.
· The number of equally spaced flat source region grids in y direction.
x keyword
<x_meshs(:)>
· Array of real. Unit is cm, size > 0, all values should be monotonically increasing.
· The x-coordinates mark flat source region grids interfaces within the region. Both using x and n_x are not allowed.
y keyword
<y_meshs(:)>
· Array of real. Unit is cm, size > 0, all values should be monotonically increasing.
· The y-coordinates mark flat source region grids interfaces within the region. Both using y and n_y are not allowed.
The Pin_geometry card defines all built-in pin geometry types used to describe the problem. It is a radial configuration of the pin-cell, including 4 types of pin-cell geometries: cylindrical pin geometry, rectangular pin geometry and two types of hexagonal pin geometry. These types of geometries are shown below:
Rectangular pin geometry types
Hexagonal pin geometry types
This card contains multiple pin_geom_type subcards, each of the subcards includes keywords: pin_geom_type, size_x, size_y, radii, r_mesh, azi_mesh, x, y, x_mesh and x_mesh.
Pin_geometry:
pin_geom_type: <id_pg>
size_x = <x_extent>
size_y = <y_extent>
[type = <rect|hexx|hexy>]
[radii = <radii(:)>]
[r_mesh = <nr_radii(:)>]
[azi_mesh = <nazi_radii(:)>]
[x = <x(:)>]
[y = <y(:)>]
[x_mesh = <x_mesh(:)>]
[y_mesh = <y_mesh(:)>]
[regions = <regions(:)>]
/pin_geom_type
/Pin_geometry
pin_geom_type keyword
<id_pg>
· String value
· Specifies the ID of one pin geometry type, which will be used in the pin block.
size_x keyword
<x_extent>
· Positive real value. Unit is cm.
· Specifies the extent of x direction of the pin geometry.
size_y keyword
<y_extent>
· Positive real value. Unit is cm.
· Specifies the extent of y direction of the pin geometry.
type keyword
<rect|hexx|hexy>
· Specifies the built-in geometry type of the pin geometry. When not given this keyword, rect type is defaultly used.
radii keyword
<radii(:)>
· Array of positive real. Unit is cm, size > 0, the values should be monotonically increasing.
· Specifies the radii of concentric cylinder, the center of which is at the center of this pin geometry.
r_mesh keyword
<nr_radii(:)>
· Array of positive integer. size = size(radii)+1.
· The first size-1 values specifie number of radial meshes between every two circles defined by radii. The last value specifies number of radial meshes between the circle defined by the last value of radii and the boundaries of the pin cell.
azi_mesh keyword
<nazi_radii(:)>
· Array of positive. size = size(radii)+1, all values must be multiples of 4, currently supporting 4, 8, 16, 32.
· The first size-1 values specifie number of azimuthal meshes between every two circles defined by radii. the last value specifies number of azimuthal meshes between the circle defined by the last value of radii and the boundaries of the pin cell.
x keyword
<x(:)>
· Array of positive real. Unit is cm, size > 0, all values should be monotonically increasing.
· The x-coordinates mark material interfaces within the pin.
y keyword
<y(:)>
· Array of positive real. Unit is cm, size > 0, all values should be monotonically increasing.
· The y-coordinates mark material interfaces within the pin.
x_mesh keyword
<x_mesh(:)>
· positive integer arry, size = size(x).
· The number of equally spaced flat source regions to be use in the grid defined by <x(:)>.
y_mesh keyword
<y_mesh(:)>
· Array of positive real integer, size = size(y).
· The number of equally spaced flat source regions to be use in the grid defined by <y(:)>.
The Pin card defines all pin types used to describe the problem. It is a definition of the pin-cell, including : ID of the pin, mat information, temperature of each mat, depletion or not. A pin is shown below:
Rectangular pin types
Hexagonal pin types
This card contains multiple pin_type subcards, each of the subcards includes keywords: pin_type, int_ID, geom, mat, is_depB and is_depMat:
Pin:
pin_type: <id_pin>
int_ID = <int_id_pin>
geom = <id_pg>
mat = <id_mat(:)>
temperature = <temps(:)>
/pin_type
/Pin
pin_type keyword
<id_pin>
· String value
· Specifies the ID of one pin type.
int_ID keyword
<int_id_pin>
· Positive integer
· Specifies the integer ID of one pin type, which will be used in the lattice card.
geom keyword
<id_pg>
· String value
· Specifies which pin geometry (defined by pin_geometry card) is used in this pin.
mat keyword
<id_mat(:)>
· Array of string value. size = number of material regions
· Specifies the id_mat of material (defined by mat card) of each material region.
temperature keyword
<temps(:)>
· Array of positive real. size = number of material regions
· Specifies the temperature of each material region.
The Lattice_geometry card defines all lattices types in 2D to describe the problem. A lattice consists of different types of pins which are defined by pin cards. A lattice is shown below:
Rectangular lattice
Hexagonal lattice
This card contains multiple lattice_type subcards, each of the subcards include two keywords: lattice_type and pinmap:
Lattice_geometry
lattice_type: <id_lat>
pinmap =
<int_id_pin> ... <int_id_pin>
. .
. .
. .
<int_id_pin> ... <int_id_pin>
/lattice_type
/Lattice_geometry
lattice_type keyword
<id_lat>
· String value
· Specifies the ID of the lattice, which is used in assembly card.
pinmap keyword
<int_id_pin>
· Array of positive integer
· Specifies the configuration of the lattice. A value of int_ID represents a pin defined by pin_type subcard.
The Assembly_geometry card defines all assembly types in 2D or 3D to describe the problem. An assembly is defined by a assembly_type subcard, which is consist of grid, gap and lattices. The grid is defined by Grid_geometry card and only one type of grid can be defined and shared by different types of assemblies. The gap is defined by gap and gap_mat keywords. The lattices are defined by axial subcard. The lattice types at different heights can be different. An assembly_type subcard contains keywords: assembly_type, grid, gap and gap_mat and 1 subcard : axial:
Assembly_geometry
assembly_type: <id_asy>
grid = <yes | no>
gap = <gap>
gap_mat = <id_mat>
axial:
height = <height>; lattice = <id_lat>
[height = <height>; lattice = <id_lat>]
/axial
/assembly_type
/Assembly_geometry
assembly_type keyword
<id_asy>
· String value
· Specifies the ID of the assembly, which will be used in core card.
grid keyword
<yes | no>
· With or without grid. If yes, the grid defined by Grid_geometry card will be used; if no, no grid will be defined. Now grid is not supported in hexagonal cases.
gap keyword
<gap>
· Positive real
· Specifies the width of the gap in this assembly.
gap_mat keyword
<id_mat>
· String value
· Specifies the id_mat of the gap material, which is defined by mat card.
axial subcard
Specifies the axial configuration of the assembly from bottom to top. This subcard contains a list of height and lattice, which defines lattices from bottom (bottom boundary of the problem) to top (top boundary of the problem).
<height>
· Positive real
· Specifies the height of the corresponding lattice in this assembly lattice keyword. The value is equal to the top of the lattice minus the bottom of the lattice
<id_lat>
· Positive integer
· Specifies the kind of the lattice by id_lat, which is defined by the lattice_geometry subcard
2.2.7. Insert_geometry card (optional)
The Insert_geometry card defineds 3D poison insertion configurations in assembly level. This card consists of multiple rod_map subcards and multiple insert_type subcards. The rod_map subcard defines the radial configurations and the insert_type defines the axial configurations. The combination of this card and insert_map keyword in Core_geometry card defines 3D poison insertion configurations in reactor core:
Insert_geometry
rod_map: <id_map>
map = < - | 1 > ... < - | 1 >
. .
. .
. .
< - | 1 > ... < - | 1 >
/rod_map
insert_type: <id_insert>
bottom = <pos_bottom>
rod_map = <id_map>
axial:
height = <height>; pin = <id_pin>
[height = <height>; pin = <id_pin>]
/axial
/insert_type
/Insert_geometry
rod_map subcard
Specifies the radial configuration of the rod position and contains 2 keywords: rod_map and map
rod_map keyword
<id_map>
· String value
· Specifies the ID of the rod_map.
map keyword
<1 | ->
· 1 means this position is inserted
· - means this position is not inserted
insert_type subcard
Defines axial configurations. This subcard contains 3 keywords: insert_type, bottom, rod_map and 1 subcard: axial
insert_type keyword
<id_insert>
· String value
· Specifies the ID of the insertion type.
<bottom> keyword
<pos_bottom>
· Positive real
· Specifies the bottom inserted position (relative position of the bottom of the inserted rods to the bottom boundary of the problem).
rod_map keyword
<id_map>
· String value
· Specifies which insert rod map is used.
axial subcard
Specifies the axial configurations from bottom top top and contains 2 keywords : height and pin
height keyword
<height>
· Positive real
· Specifies the height of the corresponding lattice (equal to top of the lattice minus bottom of the lattice) in this assembly.
pin keyword
<id_pin>
· Positive integer
· Specifies the kind of the pin
2.2.8. Control_rod card (optional)
The Control_rod card defineds 3D control rod insertion configuration in assembly level. This card consists of multiple cr_type subcards, multiple rod_map subcards, one bank subcard and one bank_pos subcard. A cr_type subcard defines a 3D control rod pin. A rod_mapsubcard defines radial configuration of the control rods in an assembly. The bank subcard defines banks of control rods in 3D. The bank_pos subcard defines the axial position of control rods. The combination of this card and cr_map keyword in Core_geometry card defines 3D control rod insertion configuration in reactor core:
Control_rod
cr_type: <id_cr>
axial:
height = <height>; pin = <id_pin>
[height = <height>; pin = <id_pin>]
/axial
/cr_type
rod_map: <id_rod_map>
map =
< - | <id_cr> > ... < - | <id_cr> >
. .
. .
. .
< - | <id_cr> > ... < - | <id_cr> >
/rod_map
bank:
ID = <id_bank>; step_size = <size>; bottom = <pos_bottom>; n_steps = <n_step>; rodMap = <id_rod_map>
[ID = <id_bank>; step_size = <size>; bottom = <pos_bottom>; n_steps = <n_step>; rodMap = <id_rod_map>]
/bank
bank_pos:
<id_bank> = <pos_bank>
[<id_bank> = <pos_bank>]
/bank_pos
/Control_rod
cr_type subcard
Contains 1 subcard axial
cr_type keyword
<id_cr>
· String value
· Specifies the ID of the control rod.
axial subcard
Specifies the control rod pin from bottom to top and contains 2 keywords : height and pin
height keyword
<height>
· Positive real
· Specifies the height of the corresponding lattice (equals lattice top minus lattice bottom) in this assembly.
pin keyword
<id_pin>
· Positive integer
· Specifies the kind of the pin by id_pin of pin_type subcard.
rod_map subcard
Contains 2 keywords: rod_map and map
rod_map keyword
<id_rod_map>
· String value
· Specifies the ID of the rod_map.
map keyword
<id_cr | ->
· id_cr means this position is inserted with control rod identified by id_cr
· - means this position is not inserted
bank subcard
Contains 5 keywords: ID, step_size, bottom, n_steps and rodMap
ID keyword
<id_bank>
· String value
· Specifies the ID of the control rod bank.
step_size keyword
<size>
· Positive real
· Specifies the size of each step of the control rod.
<bottom> keyword
<pos_bottom>
· Positive real
· Specifies the bottom position of the insertation, relative position of the bottom of the inserted rods to the bottom boundary of the problem.
n_steps keyword
<nstep>
· Positive integer
· Number of steps.
rodMap keyword
<id_rod_map>
· String value
· Specifies which rod map is used, among all the rod maps defined in rod_map subcard.
bank_pos subcard
Contains 2 keywords: id_bank and bank_pos
id_bank keyword
<id_bank>
· String value
· Specifies the ID of the control rod bank defined in bank subcard.
bank_pos keyword
<bank_pos>
· Positive value
· Specifies the position of this rod bank, relative to the bottom position of the insertion (defined by bottom keyword of bank subcard).
2.2.9. Grid_geometry card (optional)
The Grid_geometry card defines grid in reactor core. Grid consists of inner strap and outer strap radially and different types of grids axially. This card consists of multiple grid_type subcards and one grid_map subcard:
Grid_geometry
grid_type: <id_grid>
height = <height>
inner_strap:
mat = <id_mat>; thickness = <thickness>
/inner_strap
outer_strap:
mat = <id_mat>; thickness = <thickness>
/outer_strap
/grid_type
grid_map:
grid = <id_grid>; position = <pos_grid>
/grid_map
/Grid_geometry
grid_type subcard
The grid_type subcard defines one type of grid. This subcard contains 2 keywords: grid_type and height and 2 subcards: inner_strap and out_strap
grid_type keyword
<id_grid>
· String value
· Specifies the id of the grid
height keyword
<height>
· Positive real
· Specifies the height of the grid (equal to grid top minus grid bottom).
inner_strap subcard
contains 3 keywords: mat, is_act_inner and thickness
mat keyword
<id_mat>
· String value
· Specifies the id of the grid material define by mat card
thickness keyword
<thickness>
· Positive real
· Specifies the thickness of the grid
is_act_inner keyword
· logical value
· Specifies if consider the inner strap as the activation region
· Default: no
out_strap subcard
contains 3 keywords: mat, is_act_outer and thickness
mat keyword
<id_mat>
· String value
· Specifies the name of the grid material defined by mat card
thickness keyword
<thickness>
· Positive real
· Specifies the thickness of the grid
is_act_outer keyword
· logical value
· Specifies if consider the outer strap as the activation region
· Default: no
grid_map subcard
This subcard defines the axial configuration of different grids and contains 2 keywords: grid and position.
This subcard contains a list of grid and position pairs, each of which
defines the position of one grid.
grid keyword
<id_grid>
· String value
· Specifies the grid by id_grid defined in grid_type subcard
position keyword
<pos_grid>
· Positive real integer
· The axial position of the grid middle, relative to the bottom boundary of the problem
The Core_geometry card defines the configurations of reactor core, including assembly layout, poison layout, control rod layout, baffle, barrel, pad and vessel. This card contains keywords: symmetric, nx_full, ny_full and bypass_mat; subcards: bc_cond, layout, asy_map, insert_map, cr_map, baffle, barrel, pad and vessel:
Core_geometry
symmetric = < quarter | full >
nx_full = < nasy_x>
ny_full = < nasy_y>
[type = <rect|hex>]
[bypass_mat = <id_mat> ]
bc_cond:
top = <bc_top>, bottom = <bc_bottom>, east = <bc_east>, west = <bc_west>
[south = <bc_south>, north = <bc_north>]
[southeast = <bc_southeast>, northeast = <bc_northeast>,
southwest = <bc_southwest>, northwest = <bc_northwest>]
/bc_cond
layout =
< - | 1 > ... < - | 1 >
| . .
| . .
| . .
< - | 1 > ... < - | 1 >
asy_map =
<id_asy> ... <id_asy>
| . .
| . .
| . .
<id_asy> ... <id_asy>
[ insert_map =
<id_insert> ... <id_insert>
| . .
| . .
| . .
<id_insert> ... <id_insert>
]
[ cr_map =
< -- | - | <id_bank> > ... < -- | - | <id_bank> >
| . .
| . .
| . .
< -- | - | <id_bank> > ... < -- | - | <id_bank> >
]
[ baffle:
gap = <gap>, thickness = <thickness>, mat = <id_mat>
/baffle
]
[ barrel:
ir = <r_inner>, or = <r_outer>, mat = <id_mat>
/barrel
]
[ pad:
ir = <r_inner>, or = <r_outer>, mat = <id_mat>
arc_length = <length1(:)>
arc_center = <center(:)>
/pad
]
[ vessel:
ir = <r_inner>, or = <r_outer>, mat = <id_mat>
/vessel
]
/Core_geometry
symmetric keyword
<quarter | full>
· String value
· Specifies the configuration is quarter core.
· Specifies the configuration is full core.
bypass_mat keyword
<id_mat>
· String value
· Specifies the id_mat of the bypass water material, which is defined by mat card. This is needed when one of baffle, barrel, pad and vessel is defined.
nx_full keyword
<nasy_x>
· Positive integer
· Specifies the number of the assemblies in the X dirction in the core
ny_full keyword
<nasy_y>
· Positive integer
· Specifies the number of the assemblies in the Y dirction in the core
type keyword
<rect|hex>
· Specifies core geometry type. When not given this keyword, rect is used by default.
bc_cond subcard
Defines the boundary conditions. This subcard contains 10 keywords: south, north, west, east, top, bottom, northwest, southwest, northeast and southeast. User must give the first 6 keywords for rectangular case, and the last 8 keywords for hexagonal case.
south, east, top, north, west, bottom, northwest, southwest, northeast, southeast keyword
<bc_top>
· Positive integer
· 1 specifies the reflector boundary condition.
· 0 specifies the vacuum boundary condition.
<bc_bottom>
the same as <bc_top>
<bc_east>
the same as <bc_top>
<bc_west>
the same as <bc_top>
<bc_south>
the same as <bc_top>
<bc_north>
the same as <bc_top>
<bc_southeast>
the same as <bc_top>
<bc_northeast>
the same as <bc_top>
<bc_southwest>
the same as <bc_top>
<bc_northwest>
the same as <bc_top>
layout keyword
<1 | ->
· Array of string value
· 1 means this postion has assembly
· - means this postion has no assembly
asy_map keyword
<id_asy>
· Array of string value
· Specifies the assembly map by id_asy defined in assembly_type subcard
insert_map keyword
<id_insert>
· Array of string value
· – means the assembly in this position has no poison
· otherwise specifies the poison map by id_insert defined in insert_type subcard
cr_map keyword
<id_bank>
· Array of string value
· – means the assembly in this position has no control rod
· otherwise specifies the control rod map by id_bank defined in bank subcard
baffle subcards
This subcard defines the baffle around active region and contains 3 keywords: gap, thickness and mat
gap keyword
<gap>
· Positive real
· The thickness of the gap
gap_mat keyword
<id_mat>
· String value
· Specifies the id_mat of the gap material, which is defined by mat card.
thickness keyword
<thickness>
· Positive real
· Specifies the thickness of the baffle.
mat keyword
<id_mat>
· String value
· Specifies the id_mat of the baffle material, which is defined by mat card.
barrel subcards
This subcard defines the barrel and contains 3 kewords: ir, or and mat
ir keyword
<r_inner>
· Positive real
· Specifies the inner radius of the barrel.
or keyword
<o_inner>
· Positive real
· Specifies the outer radius of the barrel.
mat keyword
<id_mat>
· String value
· Specifies the id_mat of the barrel material, which is defined by mat card.
pad subcards
This subcard defines the pad and contains 5 kewords: ir, or, mat, arc_length and arc_center
ir keyword
<r_inner>
· Positive real
· Specifies the inner radius of the pad.
or keyword
<o_inner>
· Positive real
· Specifies the outer radius of the pad.
mat keyword
<id_mat>
· String value
· Specifies the id_mat of the pad material, which is defined by mat card.
arc_length keyword
<length1(:)>
· Array of positive real. size = number of the arc
· Specifies the length of the arcs.
arc_center keyword
<center(:)>
· Array of positive real. size = number of the arc
· Specifies the center of the arcs.
vessel subcards
This subcard defines the vessel and contains 3 kewords: ir, or and mat
ir keyword
<r_inner>
· Positive real
· Specifies the inner radius of the vessel.
or keyword
<o_inner>
· Positive real
· Specifies the outer radius of the vessel.
mat keyword
<id_mat>
· String value
· Specifies the id_mat of the vessel material, which is defined by mat card.
2.3. transient Block(optional)
The transient Block consists of 3 optional cards, each of which specifies the transient parameters of a module in NECP-X. A basic input of transient card is:
transient:
enable = < true | false >
time = < start_time stop_time n_perturbation >
perturbation n
time = <start_time_perturbation stop_time_perturbation n_moc_step>
perturb = <ramp | step | material>
mat_change = <materail_from material_to>
/perturbation
/transient
The enable card specifies whether the transient calculation is performed.
enable keyword
<true | false>
· logical real
· specify whether the transient calculation is performed
· Default: true
The time card specifies the start and stop time of the whole transient.
time keyword
<start_time>
· Positive real value
· Specifies the start time of the whole transient
<stop_time>
· Positive real value
· Specifies the stop time of the whole transient
<n_perturbation>
· Positive integer
· Specifies the perturbation number of the whole transient
The perturbation card specifies the perturbation time of whole transient.
perturbation keyword
<n>
· Positive integer
· Specifies the perturbation number of the whole transient
time keyword
<start_time_perturbation>
· Positive real value
· Specifies the start time of this perturbation
<stop_time_perturbation>
· Positive real value
· Specifies the stop time of this perturbation
<n_moc_step>
· Positive integer
· Specifies the MOC time step number of this perturbation
perturb keyword
<ramp | step | material>
· String value
· Specifies the type of this perturbation
mat_change keyword
<materail_from>
· String value
· Specifies the initial material
<material_to>
· String value
· Specifies the final material
The Options Block is consist of 13 optional cards, each of which specifies the computational parameters of a module in NECP-X. All options are optional. Quick input options are available from Quick User’s Guide. A basic input of Options card is:
Options:
ray
spacing = <ray_width>
quad_type = <chebyshev_yamamoto | chebyshev_mcdaniel | chebyshev_gauss>
azimuthal = <n_ang>
polar = <n_pol>
modular_type = < cell | quarter_assembly | assembly >
/ray
solver
axial_solver = <sn>
radial_solver = <moc>
parallel = <n_energy n_axial n_radial n_angle n_thread>
scatt_meth = < p0 | pn | inflow_tr | outflow_tr>
leakage = <iso>
leak_split = <no | scalar>
radial_decomposition = <default | circuit | specify>
radial_core_map =
<i_cpu | -> ... <i_cpu | -> ! 1 1 2 2 3 3
. . ! 1 1 2 2 3 3
. . ! 4 4 5 5 - -
. . ! 6 4 5 5 - -
. . ! 6 4 - - - -
<i_cpu | -> ... <i_cpu | -> ! 6 6 - - - -
/solver
cmfd
is_cmfd = <yes | no>
relaxation = <relaxation>
solver = <sweep>
k_criteria = <cmfd_k_criteria>
phi_criteria = <cmfd_phi_criteria>
n_outer = <cmfd_n_outer>
is_cmfd_fg = <yes | no>
n_outer_fg = <cmfd_n_outer_fg>
k_criteria_fg = <cmfd_k_criteria_fg>
phi_criteria_fg = <cmfd_phi_criteria_fg>
/cmfd
iteration
n_inner = <max_n_inner>
n_inner_1d = <max_n_inner_1d>
n_outer = <max_n_outer>
k_criteria = <k_criteria>
fis_criteria = <fis_criteria>
/iteration
resonance
max_n_prim = <max_n_prim>
min_num_dens = <min_density>
supercell = <0 | 1>
/resonance
th_coupling
is_enable_th = <yes | no>
th_solver = <single | subsc | ctf>
coupling_meth = <internal | external>
eps_keff = <eps_keff>
eps_p = <eps_p>
eps_tfuel = <eps_tfuel>
eps_tclad = <eps_tclad>
eps_tcoolant = <eps_tcoolant>
maxiter = <maxiter>
rlx_tfuel = <rlx_tfuel>
rlx_power = <rlx_power>
subsc
nfuel = <nfuel>
nproperty = <nproperty>
gridloss_end = <gridloss_end>
gridloss_mid = <gridloss_mid>
dheat = <dheat>
/subsc
/th_coupling
state
power = <power>
t_inlet = <t_inlet>
pressure = <pressure>
flow = <flow>
boron = <boron>
/state
multi_cycle
upd_th_frqcy = <update th frequency>
upd_xe_frqcy = <update xe_sm frequency>
upd_cb_frqcy = <update cb frequency>
save_init_value = <yes | no>
/multi_cycle
depletion
is_enable_dep = <yes | no>
dep_solver = <TTA | CRAM | QRAM>
power_density = <power density>
power_history = <power level>
burn_step=
dep = <istep>
unit = <gwd/tu | efpd>
/burn_step
tol_cram = <tolerance>
decay_step=
time = <integral decay time>
unit = <seconds | days | years>
/decay_step
coupling_method = <fpc>
energy_obtain = <typical | online>
sub_divide = <n_substep>
output_sgnc = <yes | no>
output_numden = <yes | no>
output_micro_xs = <yes | no>
output_flux = <yes | no>
restart_burn_step = <yes | no>
set_inventory = <nukid>
/depletion
xe_sm
update_xe = <yes | no>
update_sm = <yes | no>
relaxfactor = <relaxation factor>
/xe_sm
cb_search
cb_search = <yes | no>
cb_worth_guess = <guess cb worth>
rho_inlet = <rho_inlet>
k_criteria = <criteria of keff>
restrain_cb_worth = <yes | no>
b10_at_curve = <b10_at array>
b10_at_ini = <initial b10_at>
/cb_search
transient
method = <pcqs | fim>
timestep = <timestep of MOC>
tfsp = <macro | micro>
/cb_search
output
is_hdf5 = <yes | no>
is_vtk_pinpower = <yes | no>
dimensions = <2 | 3>
/output
/Options
The ray card specifies the parameters for MOC. This card contains keywords: spacing, quad_type, azimuthal, polar and modular_type.
spacing keyword
<ray_width>
· positive real
· specify the width beteewn rays
· Default: 0.03
quad_type keyword
<chebyshev_yamamoto | chebyshev_mcdaniel | chebyshev_gauss>
· string value
· specify which quadrature is used in this calculation
· Default: chebyshev_yamamoto
azimuthal keyword
<n_ang>
· positive integer
· specify the number of the azimuthal angle in each octant
· Default: 8
polar keyword
<n_pol>
· positive integer
· specify the number of the polar angle in each octant
· Default: 3
modular_type keyword
<cell | quarter_assembly | assembly>
· string value
· specify what is treated a module in MOC
· Default: assembly
This card specifies the parameters for transport solver and contains keywords: axial_solver, radial_solver, parallel, ``scatt_meth, leakage, leak_split, radial_decomposition and radial_core_map.
axial_solver keyword
<sn>
· string value
· specify the name of the axial solver
· sn: sn difference method
· Default: sn
radial_solver keyword
<moc>
· string value
· specify the name of the radial solver
· moc: method of characteristic
· Default: moc
parallel keyword
<n_energy>
· Positive integer
· Specifies the cpu number of the energy parallel (not support now)
· Default: 1
<n_axial>
· Positive integer
· Specifies the cpu number of the axial parallel
· Default: 1
<n_radial>
· Positive integer
· Specifies the cpu number of the radial parallel
· Default: 1
<n_angle>
· Positive integer
· Specifies the cpu number of the angle parallel (not support now)
· Default: 1
<n_thread>
· Positive integer
· Specifies the cpu number of the ray parallel (not support now)
· Default: 1
scatt_meth keyword
<p0 | pn | inflow_tr | outflow_tr>
· string value
· specify scattering source order and transport correction method
· pn means p1, p2, p3, p4, p5
· Default: inflow_tr
leakage keyword
<iso>
· string value
· specify isotropic leakage terms
· Default: iso
leak_split keyword
<no | scalar>
· string value
· specify the leakage splitting method
· no: don’t use
· scalar: based on the scalar flux to improve stability
· Default: no
radial_decomposition keyword
<default | circuit | specify>
· String value
· Specifies which way to decomposite the radial calculation domain
· Default: Decomposition is automatically executed line-by-line. The regions distributed to one specific core has to be continuous geometrically.
· circuit: Problem is decomposed into irregular blocks with m modules in x direction and n modules in y direction. if this decomposition method is failed, ‘specify’ way can be used based on it by user.
· Specify: User specified decomposition scheme. Convex shape is required.
radial_core_map keyword
<i_cpu>
· positive integer optional
· specify decomposition of the radial calculation domain in ‘specify’ way
· Default: No default value
This card specifies the parameters for CMFD solver and contains keywords: is_cmfd, relaxation, solver, k_criteria, phi_criteria , n_outer , is_cmfd_fg , n_outer_fg , k_criteria_fg and phi_criteria_fg.
is_cmfd keyword
<yes | no>
· With or withour cmfd
· Default: yes
relaxation keyword
<relaxation>
· Positive real
· Relaxation used in the CMFD acceleration
· Default: 1.0
solver keyword
<sweep>
· Choose CMFD solver.
· sweep : loosely coupled GMRES sweep inside NECP-X
k_criteria keyword
<k_criteria_mg>
· Positive real
· Specifies the criteria of the CMFD eigenvalue
· Default: 0.5*<iteration%k_criteria>
phi_criteria keyword
<phi_criteria_mg>
· Positive real
· Specifies the criteria of the CMFD scalar flux
· Default: 0.5*<iteration%fis_criteria>
n_outer keyword
<max_outer_mg>
· Positive integer
· Specifies the maximum number of the CMFD outer iteration
· Default: 500
is_cmfd_fg keyword
<yes | no>
· With or withour few group cmfd
· Default: no
n_outer_fg keyword
<max_outer_fg>
· Positive integer
· Specifies the maximum number of the FG-CMFD outer iteration
· Default: 500
k_criteria_fg keyword
<k_criteria_fg>
· Positive real
· Specifies the criteria of the FG-CMFD eigenvalue
· Default: 0.5*<cmfd%k_criteria>
phi_criteria_fg keyword
<phi_criteria_fg>
· Positive real
· Specifies the criteria of the FG-CMFD scalar flux
· Default: 0.5*<cmfd%phi_criteria>
2.4.4. iteration card (optional)
This card specifies the parameters for outer iteration for eigenvalue calculation and contains keywords: n_inner, n_inner_1d, n_outer, k_criteria and fis_criteria.
n_inner keyword
<max_2d_inner>
· Ppositive integer
· Specifies the maximum number of the 2D inner iteration
· Default: 1
n_inner_1d keyword
<max_1d_inner>
· Ppositive integer
· Specifies the maximum number of the 1D inner iteration
· Default: 1
n_outer keyword
<max_n_outer>
· Positive integer
· Specifies the maximum number of the outer iteration
· Default: 500
k_criteria keyword
<k_criteria>
· Positive real
· Specifies the criteria of the eigenvalue
· Default: 1.0e-5
fis_criteria keyword
<fis_criteria>
· Positive real
· Specifies the criteria of the fission source
· Default: 1.0e-4
n_sweep keyword
<max_2d_sweep>
· Positive integer
· Specifies the maximum number of the 2D bc iteration
· Default: 1
n_sweep_1d keyword
<max_1d_sweep>
· Positive integer
· Specifies the maximum number of the bc 1D iteration
· Default: 1
phi_criteria keyword
<phi_criteria>
· Positive real
· Specifies the criteria of the scalar flux
· Default: 0.0, it will not be used as the convergence criteria when it is 0.0
2.4.5. resonance card (optional)
This card specifies computational parameters for resonance self-shielding calculation module of NECP-X.
max_n_prim keyword
<max_n_prim>
· Positive integer
· Specifies the maximum number of primary nuclide.
· Default: 10
min_num_dens keyword
<min_density>
· Positive real
· Specifies minimum number density of the primary resonant nuclide.
· Default: 1e-5
supercell keyword
<0 | 1>
· Integer
· Whether use SuperCell method to treat the resonance of control rods. if ‘supercell = 0’, means do not use the method, else if ‘supercell = 1’ which means use the method.
· Default: 0
2.4.6. th_coupling card (optional)
This card contains 11 keywords: is_enable_th , th_solver, coupling_meth, eps_keff, epsp, eps_tfuel, eps_tclad, eps_tcoolant, maxiter, rlx_tfuel, rlx_power and 1 subcards: subsc
is_enable_th keyword
<yes | no>
· logical value
· enable th_coupling or not.
· The default is no
th_solver keyword
<single | subsc | ctf>
· string value
· specify the solve of the thermal hydraulic calculation.
· The default is single
coupling_meth keyword
<internal | external>
· string value
· specify the coupling method of the thermal hydraulic calculation.
· The default is internal
eps_keff keyword
<eps_keff>
· positive real
· specify the criteria of the eigenvalue.
· The default is 10 pcm
epsp keyword
<epsp>
· positive real
· specify the criteria of the power.
· The default is 1.0E-04
eps_tfuel keyword
<eps_tfuel>
· positive real
· specify the criteria of the fuel temperature.
· The default is 5 K
eps_tclad keyword
<eps_tclad>
· positive real
· specify the criteria of the clad temperature.
· The default is 1 K
eps_tcoolant keyword
<eps_tcoolant>
· positive real
· specify the criteria of the coolant temperature.
· The default is 1 K
maxiter keyword
<maxiter>
· positive integer
· specify the maximum of the th_coupling iteration.
· The default is 10
rlx_tfuel keyword
<rlx_tfuel>
· positive real
· specify the relaxation of the fuel temperature.
· The default is 0.7
rlx_power keyword
<rlx_power>
· positive real
· specify the relaxation of the power temperature.
· The default is 1.0
subsc subcard
contains 5 keywords: nfuel, nproperty, gridloss_end, gridloss_mid and dheat
nfuel keyword
<nfuel>
· positive integer
· specify the radial subring number of the fuel.
· The default is 10
nproperty keyword
<1|2>
· positive real integer
· 1: Internal property; 2: 97 water table
· The default is 1
gridloss_end keyword
<gridloss_end>
· positive real integer
· grid loss coefficient of top and end grids
gridloss_mid keyword
<gridloss_mid>
· positive real integer
· grid loss coefficient of middle grids
dheat keyword
<dheat>
· positive real integer
· percent directly to coolant
contains 5 keywords: power, t_inlet, pressure, flow and boron
power keyword
<power>
· positive real
· <power> rated thermal power
· The unit is KW
t_inlet keyword
<t_inlet>
· positive real
· specify the temperature of the inlet.
· The unit is K
pressure keyword
<pressure>
· positive real
· specify the pressure.
· The unit is bar
flow keyword
<flow>
· positive real integer
· <flow> flow of the inlet
· The unit is Kg/s
boron keyword
<boron>
· positive real integer
· <boron> initial soluble boron concentration
· The unit is ppm
2.4.8. multi_cycle card (optional)
The multi_cycle card defines the parameters in multiple-coupling calculations, including 4 keywords upd_th_frqcy, upd_xe_frqcy, upd_cb_frqcy, and save_init_value
upd_th_frqcy keyword
<upd_th_frqcy>
· Positive integer
· Specifies the frequency of updating th.
· Default: 1
upd_xe_frqcy keyword
<upd_xe_frqcy>
· Positive integer
· Specifies the frequency of updating xe_sm.
· Default: 1
upd_cb_frqcy keyword
<upd_cb_frqcy>
· Positive integer
· Specifies the frequency of updating cbc.
· Default: 1
save_init_value keyword
<yes | no>
· logical value
· Save old results of previous outer iteration or not
· Default: yes
· Warning: it must be turned on for all kinds of coupling calculations!
2.4.9. depletion card (optional)
The depletion card defines the depletion solver, power density, burnup steps, the tolerance of depletion calculation, the coupling method, the number of the sub-step and update energy dependent nfy with the mg reaction rates or not, including 11 keywords is_enable_dep , dep_solver, power_density, burn_step, tol_cram, coupling_method, decay_step, restart_burn_step, energy_obtain, sub_divide, power_history.
is_enable_dep keyword
<yes | no>
· logical value
· enable depletion or not.
· The default is no
dep_solver keyword
<TTA | CRAM | QRAM>
· String value
· Specifies which depletion method is used in the calculation.
· Default: CRAM
· TTA is transmutation trajectory analysis method
· CRAM is Chebyshev rational approximation method
· QRAM is the quadrature rational approximation method
power_density keyword
<power_density>
· Positive real, in MW/tU
· Specifies the power density.
power_history keyword
<power_history(:)>
· Positive real, no percent sign, size = number of burn_step + 1
· Specifies the power level.
burn_step keyword
burn_step:
dep = <integral burnup_depth>
unit = <dep_unit>
/burn_step:
<dep>
· Positive real, burnup or irradiation time, size = number of burnup step
<unit>
· Positive real, efpd or gwd/tu
tol_cram keyword
<tolerance>
· Positive real
· Specifies the tolerance of depletion calculation
decay_step keyword
decay_step:
time = <integral decay time>
unit = <dep_unit>
/decay_step
<time>
· Positive real, decay time, size = number of decay step
<unit>
· Positive real, seconds, days, years
energy_obtain keyword
<recoverable energy update method>
· String value
· Default: typical
· Specifies the method to calculate the recoverable energy
· typical is the typical method with raw ENDF/B-VII.0
· online is the online method
sub_divide keyword
<n_sub_step>
· Positive integer
· Default: 10
· Specifies the number of the sub-step.
output_sgnc keyword
<yes | no>
· logical value
· Output sg nuclide dependent reaction channel xs or not
· Default: no
output_numden keyword
<yes | no>
· logical value
· Output number density of isotopes for the each burn step
· Default: no
output_micro_xs keyword
<yes | no>
· logical value
· Output sg micro xs of each isotope
· Default: no
output_flux keyword
<yes | no>
· logical value
· Output sg flux and mg flux
· Default: no
restart_burn_step keyword
<restart_burn_step(:)>
· Positive real, in GWd/tU;
· Specifies burnup of restart calculation.
set_inventory keyword
<set_inventory(:)>
· Positive real
· Specifies the the zaid of isotopes those are appointed to be outputted.
2.4.10. source_term card (optional)
decay_heat keyword
<yes | no>
· logical value
· Calculate the decay heat or not
· Default: no
activity keyword
<yes | no>
· logical value
· Calculate the radioactivity or not
· Default: no
act_gammas keyword
<yes | no>
· logical value
· Calculate the activation gammas or not
· Default: no
decay_heat keyword
<yes | no>
· logical value
· Calculate the fuel gammas or not
· Default: no
neutron_src keyword
<total | sf | an | none>
· String value
· Specifies the origins of the neutron source term
· Default: fpc
· npc is the direct discretization method
photon_bound keyword
<photon_bound(:)>
· Positive real, in MeV, the energy bound of the gammas, which is in ascending order
· Specifies the energy bound of the gammas.
neutron_bound keyword
<neutron_bound(:)>
· Positive real, in MeV, the energy bound of the neutrons, which is in ascending order
· Specifies the energy bound of the neutrons.
brem_medium keyword
<none | uo2 | water>
· String value
· Specifies the bremsstrahlung medium
· Default: none
· ‘none’ means that only direct photon is considered
· ‘uo2’ means that bremsstrahlung in uo2 is considered
· ‘water’ means that bremsstrahlung in water is considered
The xe_sm includs 3 keywords update_xe , update_sm and relaxfactor.
update_xe keyword
<yes | no>
· logical value
· Update numdens of equilibrium xenon or not
· Default: no
update_sm keyword
<yes | no>
· logical value
· Update numdens of equilibrium samarium or not
· Default: no
relaxfactor keyword
<tolerance>
· Positive real
· Relaxation for equilibrium xenon calculation
2.4.12. cb_search card (optional)
The cb_search includs 7 keywords cb_search , cb_worth_guess, k_criteria, restrain_cb_worth, b10_at_curve, b10_at_ini and rho_inlet.
cb_search keyword
<yes | no>
· logical value
· Implement CBC search or not
· Default: no
cb_worth_guess keyword
<cb_worth_guess>
· Positive real
· guess cb worth for the npp
k_criteria keyword
<k_criteria>
· Positive real
· criteria of keff for cbc search
restrain_cb_worth keyword
<yes | no>
· logical value
· restrain cb worth or not
· Default: no
b10_at_curve keyword
<b10_at_curve(:)>
· Positive real, in ppm, size = number of burn_step + 1
· Specifies atomic abundance of B10 in the Boron acid.
b10_at_ini keyword
<initial b10_at>
· Positive real
· Default: 19.78%
rho_inlet keyword
<rho_inlet>
· positive real
· specify the density of the inlet.
· The unit is g/cc
2.4.13. transient card (optional)
method keyword
<fim | pcqs>
· String value
· Specifies which transient method is used.
· fim is fully implicit method.
· pcqs is predictor-corrector quasi-static method.
timestep keyword
<moc_timestep>
· Positive real
· Specifies the moc calculation timestep.
tfsp keyword
<macro | micro>
· String real
· Specifies the tfsp method.
· macro is the macro homogenization method
· micro is the nuclide-based transient fixed source method
2.4.14. output card (optional)
This card specifies some parameters of output files.In addtion, Vtk files ouput only supports serial calculataion.
is_hdf5 keyword
<no | yes>
· Logical value
· Without or with output of h5 file which describes pin power distribution
· Default: no
is_vtk_pin_power keyword
<no | yes>
· Logical value
· Without or with output of vtk file which describes pin power distribution
· Default: yes
dimensions keyword
<2 | 3>
· String value
· 2D or 3D type of vtk files output
· Default: 2