2.8.2.7. Block 13 — PMATCM — Fuel and Cladding Properties

Note: Suggested values refer to oxide fuel.

COEFDS (1)

1

kg/m^3

Solid fuel theoretical density at the reference temperature. Suggested value: 11.08E+3. Theoretical fuel density = COEFDS(1) / [1.0 + (COEFDS(2) + COEFDS(3) * (TK-273.15)) * (TK-273.15)].

COEFDS (2)

2

1/K

First-order solid fuel volumetric thermal expansion coefficient, ALPHA1. Suggested value: 2.04E-5.

COEFDS (3)

3

1/K^2

Second-order solid fuel volumetric thermal expansion coefficient, BETA1 Suggested value: 8.70E-9. Used only if IRHOK > 0.

COEFK (1-7)

4-10

Fuel thermal conductivity coefficients. Fuel thermal conductivity = ((COEFK(1) - FDEN) * FDEN - 1.0) * ((COEFK(2) + COEFK(3) * TK)-1 + COEFK(4) * TK3) if FDEN ≤ 0.95, and thermal conductivity = (3.0 * FDEN -1.0) * ((COEFK(5) + COEFK(6) * TK)-1 + COEFK(7) * TK3) if FDEN > 0.95, where FDEN is fractional fuel density. Suggested values: 2.1, 2.88E-3, 2.52E-5, 5.83E-10, 5.75E-2, 5.03E-4, 2.91E-11. Used only if IRHOK = 2.

EXKTB (L,ICLAD)

11-70

W/m-K

Table of clad thermal conductivity values for clad ICLAD, 1 ≤ L ≤ 20. See EXKTM for corresponding temperature values.

If only EXKTB(1) is entered, property is temperature-independent.

(1 ≤ ICLADICLAD1)

EXKTM (L)

71-90

K

Temperature values for EXKTB table, 1 ≤ L ≤ 20.

RHOTAB (L,IFUEL)

91-250

kg/m^3

Table of theoretical fuel density for fuel IFUEL, 1 ≤ L ≤ 20. See RHOTEM for corresponding temperature values.

Used for IMETAL = 0. See RHOZNfor IMETAL > 0.

RHOTEM (L,IFUEL)

251-410

K

Temperature values for RHOTAB table, 1 ≤ L ≤ 20, for fuel IFUEL.

Note: If fuel solidus and liquidus temperatures are defined for fuel melting (see TFSOL and TFLIQ), then two adjacent entries for these temperatures should be provided in this table.

TMF (IFUEL)

411-418

K

Not to be input. It is set to fuel solidus temperature in the code. See TFSOL.

TR

419

K

Reference design point temperature. Temperature at which pin dimensions are measured. Suggested value: 300.

XKTAB (L,IFUEL)

420-579

W/m-K

Table of fuel thermal conductivity values for fuel IFUEL, 1 ≤ L ≤ 20. See XKTEM for corresponding temperature values.

If only XKTAB(1) is entered, property is temperature-independent.

(1 ≤ IFUELIFUEL1)

XKTEM (L)

580-599

K

Temperature values for XKTAB table, 1 ≤ L ≤ 20.

FGMM

600

g/mol

Molecular weight of fission-gas atom. Suggested value: 131.

GATPF

601

Gas atoms generated per fission. Suggested value: 0.246.

ENPF

602

MeV

Energy per fission. Suggested value: 197.

RLEQ

603

Fraction of the as-fabricated porosity which defines the equiaxed / columnar fuel boundary. Suggested value: 0.6. PRSTY2 < RLEQ * PRSTY - columnar fuel PRSTY2 > RLEQ * PRSTY - equiaxed fuel

RUEQ

604

Grain size ratio at the equiaxed / as-fabricated boundary. Suggested value: 1.2. DGR2 < RUEQ * DGO - as-fabricated DGR2 ≥ RUEQ * DGO - equiaxed

PRSMIN

605

Minimum attainable porosity during restructuring. Suggested value: 0.02.

CPFTAB (L,IFUEL)

606-765

J/kg-K

Table of fuel specific heat values for fuel IFUEL, 1 ≤ L ≤ 20. See CPFTEM for corresponding temperature values.

If only CPFTAB(1) is entered, property is temperature-independent.

(1 ≤ IFUELIFUEL1)

CPFTEM (L)

766-785

K

Temperature values for CPFTAB table, 1 ≤ L ≤ 20.

TFSOL (IFUEL)

786-793

K

Fuel solidus temperature.

TFLIQ (IFUEL)

794-801

K

Fuel liquidus temperature.

UFMELT (IFUEL)

802-809

J/kg

Fuel heat of fusion.

TESOL (ICLAD)

810-812

K

Cladding solidus temperature.

TELIQ (ICLAD)

813-815

K

Cladding liquidus temperature.

UEMELT (ICLAD)

816-818

J/kg

Cladding heat of fusion.

CPCTAB (L,ICLAD)

819-878

J/kg-K

Table of clad specific heat values for clad ICLAD, 1 ≤ L ≤ 20. See CPCTEM for corresponding temperature values.

If only CPCTAB(1) is entered, property is temperature-independent.

(1 ≤ ICLADICLAD1)

CPCTEM (L)

879-898

K

Temperature values for CPCTAB table, 1 ≤ L ≤ 20.

TME (ICLAD)

899-901

K

Not to be input. Set to cladding solidus temperature in the code. See TESOL.

UMELT (IFUEL)

902-909

Not currently used.

YLDTAB (L,ICLAD)

910-969

Pa

Table of clad yield values for clad ICLAD, 1 ≤ L ≤ 20. See YLDTEM for corresponding temperature values.

If only YLDTAB(1) is entered, property is temperature-independent.

(1 ≤ ICLADICLAD1)

YLDTEM (L)

970-989

K

Temperatures values for YLDTAB table.

CROETB (L,ICLAD)

990-1049

J/m^3-K

Specific heat * density for cladding in table location L, 1 ≤ L ≤ 20. See CROETM for corresponding temperature values.

If only CROETB(1) is entered, property is temperature-independent.

CROETM (L)

1050-1069

K

Temperature values for CROETB table.

CE (ICLAD)

1070-1072

J/kg-K

Cladding specific heat at solidus temperature for CLAP cladding motion module. 1 ≤ ICLAD ≤ 3. Suggested value: 690.

PRSTY (IFUEL)

1073-1080

As-fabricated porosity for each fuel type. IFUEL ≤ 8.

AC

1081

Not currently used.

QSWL

1082

Not currently used.

APORE

1083

m^2-K^1.5/s

Pre-exponential factor in pore velocity.

VPORE = APORE * (dT/dr) * exp(-QPORE/(RGASSI * T)) / (T ** ABC)

Suggested value: 20.704.

QPORE

1084

J/gm-mole

Pore migration activation energy Suggested value: 4.5281E05.

ABC

1085

Exponent of temperature factor in pore velocity. Suggested value: 1.5.

RGASSI

1086

J/gm-mole-K

Ideal gas constant. Suggested value: 8.31434.

GAMMA

1087

J/m^2

Fuel surface tension. Suggested value: 0.45. See SUFU.

APG

1088

Pa

Pre-exponential factor in bubble radius parameterization. Suggested value: 5.0E04. | RB = (2 * GAMMA/APG) * exp (-QPG / (RGASSI * TEMP))

QPG

1089

J/mole

Temperature dependence of bubble radius. Suggested value: 5.65065E04.

GK

1090

m^3/s

Pre-exponential factor in unlimited grain growth rate. DG ** NGRAIN = DGO ** NGRAIN + GK * TIME * exp (- QV / (RGASSI * TEMP)) Suggested value: 1.717E10.

QV

1091

J/gm-mole

Activation energy of unlimited grain growth rate. Suggested value: 3.87E05.

GK1

1092

m^2/s

Pre-exponential factor in limited grain growth rate. (Ainscough et al. model). Suggested value: 1.45556E-08.

QV1

1093

J/mole-K

Temperature dependence in limited grain growth rate. Suggested value: 2.67E+5.

GRAINK

1094

m

Pre-exponential factor in maximum grain size. DMAX = GRAINK * exp(-GRAINQ / (RGASSI* TEMP))

GRAINQ

1095

J/gm-mole

Temperature dependence in maximum grain size. Suggested value: 6.3375E+04.

CVXE

1096

J/kg-K

Xenon specific heat at constant volume. Suggested value: 94.69.

CVHE

1097

J/kg-K

Helium specific heat at constant volume. Suggested value: 3.13E+03.

ROFF

1098

m

Surface roughness of fuel. Suggested value: 3.3E-06.

ROFC

1099

m

Surface roughness of inner cladding. Suggested value: 1.78E-06.

AZEROX

1100

Calibration factor in solid-solid conductance. Not currently used.

GAMGS

1101

Cp/Cv parameter in jump distance calculation. Suggested value: 1.66.

HARDNS

1102

Pa

Meyer’s hardness of the softer contacting surface in solid-solid gap conductance. This is set to 3 * yield stress within the code.

ET

1103

Exponent of the pressure dependence in solid-solid conductance. Suggested value: 1.

ACCHE

1104

Accommodation coefficient of helium. Suggested value: 0.15.

ACCXE

1105

Accommodation coefficient of xenon. Suggested value: 0.805.

CZERO

1106

Calibration constant for surface roughness in gap conductance calculation. Suggested value: 1.98.

STEBOL

1107

W/m^2-K^4

Stefan-Boltzmann constant. Suggested value: 5.67E-08.

EMSF

1108

Fuel emissivity. Suggested value: 0.9.

EMSC

1109

Cladding emissivity. Suggested value: 0.8.

QA1

1110

K

Parameter in Weisman fission-gas release model. Probability of escaping directly without being trapped, KPRIME = exp(-QA1/ TEMP - QA2 - QA3 * DEN) where DEN = percent of fuel theoretical density. Suggested value: 6.92E+3.

QA2

1111

Parameter in Weisman fission-gas release model. Suggested value: 33.95.

QA3

1112

Parameter in Weisman fission-gas release model. Suggested value: 0.338.

QA4

1113

K

Parameter in Weisman fission-gas release model. Probability of trapped fission-gas atom getting released from trap and then escaping per second, K = exp(-QA4/ TEMP - QA5). K is in units of 1/s. Suggested value: 1.48E+04.

QA5

1114

Parameter in Weisman fission-gas release model. Suggested value: 9.575.

ALFSS

1115

1/s

Pre-exponential factor in isotropic fission- gas release model. Fractional release rate= ALFSS * exp(-BETSS/TEMP). Suggested value: 2.0E-04.

BETSS

1116

K

Temperature dependence in isotropic fission-gas release model. Suggested value: 1.1E+04.

CNU

1117

Cladding Poisson ratio. Suggested value: 0.3.

FNU

1118

Fuel Poisson ratio. Suggested value: 0.3265.

AM

1119

Stress exponent in the fuel creep law for stress relaxation calculation. Strain rate = AONE * stress ** AM * exp(-QLAX/(RGASSI * Temp)). “AONE” is evaluated in the code depending on fractional fuel density and fuel grain size. Suggested value: 1.0.

QLAX

1120

J/mole

Activation energy for diffusion creep. Suggested value: 3.77E+05.

QLAX2

1121

Not currently used.

DDX

1122

Not currently used.

DDX2

1123

Not currently used.

RGAS

1124

Pa-m^3/kg-K

Gas constant per kilogram for fission-gas (as in PV = MRT). Suggested value: 65 for high burnups.

PLUTO2 AND LEVITATE Input (1125-1199, 1206-1217, 1229-1257)

CINAF0

1125

Fraction of the coolant flow area occupied by the liquid sodium film left behind by moving coolant slugs in PLUTO2. This is also the maximum value in the voided channel. CINAF0 must be < CIVOID. See WFS00 and WF0 to input consistent values. Suggested value: 0.15.

CIBBIN

1126

If the liquid fuel volume fraction in the channel is greater than CIBBIN, the fuel flow regime is treated as a bubbly flow regime. See VFNALQ and CIANIN.

CIREFU

1127

Reynolds number for annular or bubbly fuel flow above which the friction factor is assumed to be constant and equal to CIFRFU.

CIFRFU

1128

Moody friction factor for turbulent bubbly fuel flow (See CIREFU).

CIFUMO

1129

Fraction of the axial momentum of the fuel flow in the pin which is retained by the fuel which is ejected into the coolant channel.

CIVOID

1130

If the sodium void fraction in the coolant channel is less than CIVOID the heat-transfer and friction between sodium and cladding are based on single- phase correlations for the homogeneous mixture of the two phases of sodium. CIVOID must be > CINAF0 and < CIA4. For sodium void fractions greater than CIVOID see CIA4 and HCFFMI. See Table 14.4.1.

CIA1

1131

Constant in the fuel particle-to-sodium heat-transfer coefficient. H = CIA1*(conductivity of fuel)/(particle radius) * (1-Na void fraction) ** CIA2. (See Eqs. 14.4-94 and 14.4-98).

CIA2

1132

(See CIA1).

CIA3

1133

Constant in the molten fuel-to-cladding and molten fuel-to-solid fuel heat-transfer coefficient. Constant for oxide fuel but strongly dependent on Reynolds number for metal fuel. (See Eqs. 14.2-29, 14.4-118, and 14.4-125).

CIA4

1134

If the sodium void fraction is greater than CIA4, the heat-transfer coefficient between two-phase sodium and cladding, moving fuel and fuel crust is based on an interpolation. CIA4 must be > CIVOID. (See Eqs. 14.4-88, 14.4-103 and 14.4-107 in the documentation).

CIA5

1135

Constant in the fuel particle-to-sodium / fission-gas drag which controls the dependence on the void fraction. (See Eq. 14.4-163 in the documentation). Suggested value: -1.7.

CIA6

1136

Constant in the bubbly fuel flow drag calculation (See Eq. 14.4-170). Suggested value: 0.4272.

CIFN

1137

Not currently used.

FNFUAN

1138

Not currently used.

CPFU

1139

J/kg-K

Average specific heat of moving liquid or solid fuel.

CDFU

1140

J/m-s-K

Average thermal conductivity of moving liquid or solid fuel.

CMNL

1141

Pa^-1

Average compressibility of liquid sodium at roughly the sodium temperature at the time of pin failure in the vicinity of failure.

CDNL

1142

J/m-s-K

Average thermal conductivity of liquid sodium at roughly the sodium temperature at the time of pin failure in the vicinity of failure.

CIETFU

1143

Effectiveness of fuel particles to entrain or tear off a liquid sodium film. CIETFU = 1.0 means that the fuel acts as a gas with the gas density equal to the fuel smear density. For CIETFU = 0.1 only one tenth of the fuel density is used.

CDVG

1144

J/m-s-K

Average thermal conductivity of the sodium vapor / fission-gas mixture at temperatures roughly 200-300 K higher than the sodium temperature at the time of pin failure in the vicinity of failure. Used only in Dittus-Boetter correlation for Nusselt numbers. At present, use sodium vapor value.

VIFI

1145

kg/m-s

Average viscosity of fission-gas.

CFNACN

1146

J/m^2-s-K

Sodium condensation coefficient.

CFNAEV

1147

J/m^2-s-K

Sodium evaporation coefficient. Should be larger than the above condensation coefficient.

FIFNGB

1148

Fraction of the fission-gas entering the cavity with the melting-in fuel which is on grain boundaries. This fraction of the fission-gas becomes immediately available, whereas the remainder becomes available only after a coalescence time. Suggested value: 0.10. (See CIRTFS)

VINL

1149

kg/m-s

Average viscosity of liquid sodium at roughly the sodium temperature at the time of pin failure in the vicinity of failure.

VIVG

1150

kg/m-s

Average viscosity of the fission-gas/ sodium-vapor mixture. (For temperature range and other comments, see CDVG).

EGFUSO

1151

J/kg

Internal energy of fuel at the solidus point.

DZPLIN

1152

m

Minimum length of the edge cells in the interaction region of PLUTO-2 and LEVITATE. Values between 0.005 and 0.05 meter are allowed. DZPLIN has to be smaller than the shortest mesh cell in all channels. Recommended and default value: 0.02.

CFCOFV

1153

Condensation heat-transfer coefficient for fuel vapor. :units: J/m^2-s-K

CFFURH

1154

Not currently used.

C1VIPR

1155

A dimensionless constant in the artificial viscous pressure calculation inside the pin. (See Eq. 14.2-38a)

C2VIPR

1156

A dimensionless constant in the artificial viscous pressure calculation inside the pin. (See Eq. 14.2-38)

SUFU

1157

J/m^2

Molten fuel surface tension. (See GAMMA)

RAFPLA

1158

m

Radius of initial fuel particles.

RAFPSM

1159

m

Radius of fuel particles after fragmentation, after TIFP s from initial injection.

VFNALQ

1160

Liquid sodium volume fraction in the coolant channels below which a continuous (annular or bubbly) fuel flow regime can be initiated (See CIBBIN, CIANIN, and EGMN used in determining fuel flow regimes).

EGBBLY

1161

J/kg

If the fuel flow regime is annular or bubbly, fuel freezing may be initiated when the fuel internal energy drops below EGBBLY. Its value should be above the solidus energy.

VIFULQ

1162

kg/m-s

Viscosity of the fuel above the fuel liquidus.

VFNARE

1163

Liquid sodium volume fraction above which a continuous fuel flow becomes a particulate flow again. Suggested value: >0.5. (See Figure 14.4.4)

DTPLIN

1164

s

Initial and minimum PLUTO2 and LEVITATE time step. Suggested value: 2.E-5. Minimum value: 1.E-6. Maximum value: 2.E-4.

AXMX

1165

m^2

Reference area for PLUTO2 and LEVITATE. This area times 1 meter is the volume to which all volume fractions in PLUTO2 or LEVITATE are referenced. It makes the volume fractions more meaningful if this area is equal to the area encompassing everything inside the outer perimeter of the subassembly wall (not per fuel-pin but per fuel subassembly).

EPCH

1166

Not currently used.

TIPLMX

1167

s

Time after PLUTO2 initiation when full PLUTO2 calculations are switched off and only the PLUTO2 energy equations are solved for all components which are then assumed to remain stagnant. Necessary for transient overpower calculations in which the lead channel fails many seconds before any other channel.

DTPLP

1168

s

Full PLUTO2 or LEVITATE printout every DTPLP seconds.

FNMELT

1169

Molten fuel is added to the cavity when it has gone through a fraction FNMELT of the heat of fusion. Suggested value: 0.9 (for TREAT experiment analysis lower values may be necessary).

CIRTFS

1170

1/s

Determines how fast dissolved fission-gas in the pin cavity coalesces and becomes free gas: Mass of fission-gas coalescing per unit time = CIRTFS * current mass of dissolved fission-gas in this node. Suggested value: 16.667.

CISP

1171

Not currently used.

CIFUFZ

1172

Controls the mode of fuel freezing in PLUTO2.

= 0, Conduction type freezing.
= 1, Bulk type freezing.

Allowed range between 0.0 to 1.0. Suggested value: 1.

TIFP

1173

s

Time delay for fragmentation of larger particles into smaller ones (relative to initial fuel injection time, see IPSIZE).

CIANIN

1174

Channel fuel (moving fuel + frozen fuel) volume fraction above which the whole perimeter of the channel is wetted by molten fuel in annular flow.

TEFAIL

1175

K

Cladding temperature of a node above which the cladding failure propagates to this node if the pin pressure is greater than the channel pressure + PRFAIL and also the areal fuel melt fraction greater than FNARME. Both cladding nodes must exceed this temperature. Relevant only if axial pin failure propagation is determined by input, if KFAILP = 1. Suggested value: Steel solidus temperature TESOL.

FNARME

1176

Relevant for both axial pin failure propagation options (KFAILP = 0 or 1). FARME is the minimum areal fuel melt fraction of a node above which a cladding failure can propagate into this node if additional conditions depending upon the value of KFAILP are satisfied.

PRFAIL

1177

Pa

Relevant only if KFAILP = 1. (See TEFAIL).

EGMN

1178

J/kg

The continuous fuel flow regimes cannot be initiated below this fuel internal energy. Its value should be above the solidus energy.

HCFFMI

1179

J/m^2-s-K

Convective heat-transfer coefficient from the surface of a frozen fuel crust to two-phase sodium/fission-gas mixture (liquid sodium in the form of dispersed drops) with a void fraction > CIVOID.

HCFUBB

1180

J/m^2-s-K

Convective heat-transfer coefficient between the interior of the molten fuel and two-phase sodium/fission gas mixture bubble surfaces in the bubbly flow regime.

FNHTFU

1181

Fraction of the convective heat-transfer coefficient between liquid fuel and cladding which remains effective when the moving fuel consists of solid chunks.

XPL5

1182

For future use in PLUTO2.

XPL6

1183

For future use in PLUTO2.

TECLMN

1184

K

Maximum outer cladding node temperature above which freezing fuel cannot stick to the cladding (the same input value limits the freezing on the inner structure node). (this is used in PLUTO2 only).

TECLRL

1185

K

Temperature of the middle cladding node above which plated-out fuel is released. (this is used in PLUTO2 only).

CIHCFU

1186

Dimensionless coefficient in the Deissler heat-transfer correlation for inpin fuel motion. Nu = CIHCFU*Pr*Re0.8

HCCLMI

1187

J/m^2-s-K

Convective heat-transfer coefficient from hotter cladding to two-phase sodium/ fission-gas mixture (liquid sodium in the form of dispersed drops) with a void fraction > CIVOID.

CMFU

1188

Pa^-1

Average adiabatic compressibility of liquid fuel.

XPL7

1189

For future use in PLUTO2.

XLP8

1190

For future use in PLUTO2.

XLP9

1191

For future use in PLUTO2.

XPL10

1192

For future use in PLUTO2.

XPL11

1193

For future use in PLUTO2.

XPL12

1194

For future use in PLUTO2.

CDCL

1195

J/m-s-K

Average conductivity of the solid cladding.

CPCL

1196

J/kg-K

Average specific heat of the solid cladding.

CPCLRH

1197

J/m^3-K

Average specific heat times density of the solid cladding.

RHSLBT

1198

kg/m^3

Average physical density of the lower liquid sodium slug.

RHSLTP

1199

kg/m^3

Average physical density of the upper liquid sodium slug.

COEFDL (1)

1200

Not currently used.

COEFDL (2)

1201

1/K

Molten fuel volumetric thermal expansion coefficient, ALPHA2. (DEFORM uses with COEFDS(1)) Suggested value: 9.3E-5. Rho = COEFDS(1)/(1+COEFDL(2) *(T-273.15))

QSTAR

1202

Not currently used.

ABCPU

1203

Not currently used.

QPU

1204

Not currently used.

DPUO

1205

Not currently used.

RHSSLQ

1206

kg/m^3

Density of steel in the fuel crust. (See CPCL, CPCLRH, and RHSSSO). Suggested value: 6000.

CIBBDI

1207

Liquid fuel volume fraction above which the transition from annular to bubbly fuel flow regime occurs in disrupted regions (i.e., regions having no pin geometry). Suggested value: 0.2.

CIANDI

1208

Liquid fuel volume fraction above which the transition from partial perimeter annular to full perimeter fuel flow regime occurs in disrupted regions. Suggested value: 0.1.

CIVIMT

1209

The fuel viscosity at solidus is set equal to CIVIMT times the value at liquidus (See VIFULQ). The fuel viscosity between solidus and liquidus is evaluated by interpolation between these two values. Suggested value: 200.

EGSESO

1210

J/kg

Solidus energy of steel. Suggested value: 8.18E+5.

EGSELQ

1211

J/kg

Liquidus energy of steel. Suggested value: 1.076E+6.

CPSE

1212

J/kg-K

Specific heat of molten steel. (See CPCTAB, CE, CPCL, and CPCLRH). Suggested value: 768.

FRMRSE

1213

The fraction of latent heat of fusion to be satisfied for steel to be considered a moving fluid in LEVITATE. Suggested value: 0.5.

FNSROS

1214

Initial fraction of structure in the inner node (facing the channel). (See DSTIZ and DSTOZ for consistent input). Suggested value: 0.1 to 0.9.

RHSSSO

1215

kg/m^3

Density of solid steel. (See CPCL, CPCLRH and RHSSLQ). Suggested value: 6.95E+3.

RGFV

1216

J/kg-K

Gas constant for the fuel vapor. Suggested value: 31.

RGSV

1217

J/kg-K

Gas constant for the steel vapor. Suggested value: 145.

TMIDFG

1218

Not currently used.

FGSPRD

1219

Not currently used.

FGPORX

1220

Not currently used.

WST

1221

Not currently used.

HECOND

1222

Not currently used.

FGCOND

1223

Not currently used.

AKCOND

1224

Not currently used.

HEMM

1225

Molecular mass of helium atom. Suggested value: 4.

EPSSFP

1226

Per^a/o burn-up

Volume swelling fraction due to solid fission products. Suggested value: 3E-03.

HEMASX

1227

Not currently used.

ZSWFAC

1228

Not currently used.

FNDISR

1229

Ratio of molten cavity radius to fuel pellet radius needed for disrupting pins in LEVITATE. Pins can also disrupt if the outermost fuel node is above the solidus. (DTDISR must also be met).

DTDISR

1230

K

Fuel-pin disruption in LEVITATE is allowed if the cladding middle node temperature is greater than cladding solidus temperature minus DTDISR. (FNDISR must also be met). Not currently used.

SRFMLE

1231

If SRFMLE = 0.0, liquid sodium film on structure is thrown away in LEVITATE. If SRFMLE > 1.E-10, the sodium in the structure film is conserved. LEVITATE mixes the sodium film with the sodium vapor in the channel. This can lead to an excessive pressure event in the channel due to fuel/sodium interactions.

XLE4

1232

Not currently used.

XLE5

1233

Not currently used.

XLE6

1234

Not currently used.

XLE7

1235

Not currently used.

XLE8

1236

Not currently used.

XLE9

1237

Not currently used.

XLE10

1238

Not currently used.

XLEPT1

1239

Not currently used.

XLEPT2

1240

Not currently used.

XLEPT3

1241

Not currently used.

XLEPT4

1242

Not currently used.

XLEPT5

1243

Not currently used.

XLEPT6

1244

Not currently used.

XLEPT7

1245

Not currently used.

XLEPT8

1246

Not currently used.

XLEPT9

1247

Not currently used.

PLUT1

1248

Not currently used.

PLUT2

1249

Not currently used.

PLUT3

1250

Not currently used.

PLUT4

1251

Not currently used.

PLUT5

1252

Not currently used.

PLUT6

1253

Not currently used.

PLUT7

1254

Not currently used.

PLUT8

1255

Not currently used.

PLUT9

1256

Not currently used.

PLUT10

1257

Not currently used.

FAXIAL

1258

Fraction of calculated axial expansion to be actually used by DEFORM. Suggested value: 1. (See EXPCOF).

FCLDWK

1259

Initial cold-work strain of the cladding. (Required if IYLD = 1).

FMELTD

1260

Not currently used.

FSTRAN

1261

Not currently used.

FTMPCH

1262

Fraction of fuel or blanket melt temperature (TMF(IFUEL)) at which crack healing is assumed. (Required if IHEALC = 2).

EXPCOF

1263

Fraction of the axial expansion reactivity calculated by DEFORM to be used for feedback effects. (See FAXIAL). 0.0 ≤ EXPCOF ≤ 1.0. Suggested value: 1.0.

PRTSTR

1264

s

Time for the first transient printout if IPROPT = 1.

PRTDEL

1265

s

Time interval between printouts if IPROPT = 1.

FIRLIM

1266

Failure fraction at which the main time step is cut to DTFALL. For each fuel pin failure option a time-dependent fraction between 0.0 and 1.0 called failure fraction is defined for each fuel axial segment which indicates how close to pin failure the axial segment is at the current time. Failure fraction is 0.0 at the beginning of the transient, and equals 1.0 at the time of pin failure. (See MFAIL).

SECLIM

1267

Failure fraction at which the main time step is cut to DTFAL2.

THRLIM

1268

Failure fraction at which the main time step is cut to DTFAL3.

DTFAL1

1269

s

Main time step when FIRLIM ≤ failure fraction < SECLIM.

DTFAL2

1270

s

Main time step when SECLIM ≤ failure fraction < THRLIM.

DTFAL3

1271

s

Main step when THRLIM ≤ failure fraction < 1.0.

AKD

1272

Not currently used.

CKD

1273

Not currently used.

QKD

1274

Not currently used.

FGFI

1275

Mole fraction of fission gas in the initial fill-gas. (Assumed same molecular weight as FGMM).

CIPINJ

1276

Controls the ejection of molten fuel/ fission gas from the pin cavity when the mechanistic ejection model is not used. See INRAEJ. Suggested value: 2.5E4.

DTPNIN

1277

s

Initial and minimum PINACLE time step. Suggested value: 2.E-5.

TIPNMX

1278

s

PINACLE maximum time. Not currently used.

DTPNP

1279

s

Full PINACLE printout every DTPNP seconds.

ASRALU

1280

Aspect ratio of cylindrical chunks = 2R/L. Recommended value = 1.

UN1281

1281

Not currently used.

UN1282

1282

Not currently used.

UN1283

1283

Not currently used.

RALUDI

1284

Radius of chunks generated by pin disruption.

RALUFZ

1285

Radius of chunks generated by freezing and crust break-up. If set to zero the code provides default values based on local geometry. Recommended value: 0.

CINAPN

1286

= 0, All the sodium vapor pressure is added to the local pressure.
= 1, Only the excess of the sodium vapor pressure over the fission gas and fuel vapor pressure is added to the local pressure.

Note: This variable is relevant only if INAPN is equal to 1.

CPCM

1287

Chemical equilibrium coefficient of Pu at center-to-middle zone interface used in computing zone formation in U-Pu-Zr alloy fuel. Suggested value: 1.177.

CPMO

1288

Chemical equilibrium coefficient of Pu at center-to-outer zone interface used in computing zone formation in U-Pu-Zr alloy fuel. Suggested value: 1.0723.

CZCM

1289

Chemical equilibrium coefficient of Zr at center-to-middle zone interface. Suggested value: 9.79.

CZMO

1290

Chemical equilibrium coefficient of Zr at center-to-outer zone interface. Suggested value: 7.84.

CUCM

1291

Chemical equilibrium coefficient of U at center-to-middle zone interface. Suggested value: 0.448.

CUMO

1292

Chemical equilibrium coefficient of U at center-to-outer zone interface. Suggested value: 0.5866.

EPSMS

1293

kg

Criterion for zonal fuel mass convergence in computing zone formation in U-Pu-Zr alloy fuel. Suggested value: 1.0E-6

EPSCOM

1294

Criterion for the convergence of zonal weight fractions of Pu and Zr. Suggested value: 1.0E-3

CIPNTP

1295

Controls the calculation of the fuel pin top boundary temperature, which is important in triggering the axial in-pin fuel relocation.

= 0, Boundary temperature is equal to the temperature of the material in the node above the active fuel.
= 1, The boundary temperature is the same as the temperature of the central top node of the active fuel.
= 2, This option is available for metal fuel pins only. The in-pin fuel motion is triggered by a mechanistic model using 2-d temperature distributions for the top fuel node. (This option is not yet available.)

ROGSPI

1296

Mass of fission gas generated in the fuel pin per unit volume of the original pin and percent burnup. Used to set the fission gas arrays only if DEFORM is not used (ISSFUE = 0).

PRSFTN

1297

Partial pressure of dissolved gas, due to surface tension. This pressure is calculated as 2 x SIGMA/R. The recommended value for oxide fuel is 320 x 10**5 Pa. (SIGMA = 400 x 10-3 N/m, R = 250 x 10**-10 m).

COLFAC

1298

Multiplier on the sodium density in the coolant reactivity calculation. Suggested value: 1.0.

GAMGAS

1299

Cp/Cv for pin plenum gas, P*V**GAMGAS = constant for adiabatic changes. Typical values: 1.3 - 1.6.

METAL FUEL PROPERTIES DATA

PUZRTP (L,IFUEL)

1300-1315

Metal fuel plutonium and zirconium weight fractions by fuel type (IFUEL). Used for IMETAL > 1. L=1, Plutonium weight fraction. L=2, Zirconium weight fraction.

RHOZN (IFUEL)

1316-1323

Metal fuel theoretical density at the reference temperature (TR) by fuel type (IFUEL). Used for IMETAL > 1. If RHOZN = -1.0, then it is internally evaluated based on the input composition (PUZRTP). If RHOZN = 0.0, then the fuel type IFUEL does not use the IFR Handbook-interpolated U-Pu-Zr alloy fuel properties of input option IFUELM = 0.

XLOGNA (IFUEL)

1324-1331

Metal fuel porosity fraction logged by bond sodium by fuel type (IFUEL). Used for IMETAL > 1.

XSIGMC

1332

To account for uncertainties in IFR handbook data for U-Pu-Zr and U-Zr alloy fuel heat capacity, add |XSIGMC| standard deviations (subtract if XSIGMC is negative) to the best estimate.

XSIGMK

1333

To account for uncertainties in IFR handbook data for U-Pu-Zr and U-Zr alloy fuel thermal conductivity, add |XSIGMK| standard deviations (subtract if XSIGMK is negative) to the best estimate. The standard deviation depends on fuel burnup (See BURNFU).

XSIGMD

1334

To account for uncertainties in IFR handbook data for U-Pu-Zr and U-Zr fuel theoretical density, add |XSIGMD| standard deviations (subtract if XSIGMD is negative) to the best estimate.

APROPI (I)

1335-1394

Coefficients for user-defined coolant properties.

APROPI(1:59) corresponds to the \(A_i\) defined in the coolant property equations of Section 12.13. APROPI(60) normally corresponds to the coolant critical temperature, \(T_c\). See Eq. (12.13-7).

DUMPMC

1395-1725

Not currently used.