2.8.2.14. Block 63 — PMATCH — Channel-Dependent Properties Input¶

TIMCNS

1

s

Time constant for fuel pin heat transfer. Default = 0.1.

AHBPAR

2

W/m^2-K\ \ \ m^2-K/W-m

If all three parameters are not equal to 0.0, the bond correlation is of the form:

HB = AHBPAR + 1.0/(BHBPAR +(gap size + CHBPAR)/HBPAR)

BHBPAR

3

see AHBPAR

CHBPAR

4

see AHBPAR

HBMAX

5

W/m^2-K

Maximum value of bond conductance when a gap exists; minimum value when a gap does not exist.

Default when AHBPAR, BHBPAR, and CHBPAR > 0.0:

HBMAX = AHBPAR

+ 1.0/(BHBPAR+CHBPAR/HBPAR)

HBMIN

6

W/m^2-K

Minimum value of bond conductance.

HBPAR

7

W/m-K

If all three parameters in AHBPAR, BHBPAR, and CHBPAR are zero, then the bond conductance equation when a gap exists is of the form: Bond conductance = HBPAR/gap.

HSNK

8

Should be set to 0.0.

TSNK

9

Should be set to 0.0.

DPRSTY

10

Not currently used.

XKSTIZ (KZ)

11-17

W/m-K

Inner structure thermal conductivity in zone KZ.

XKSTOZ (KZ)

18-24

W/m-K

Outer structure thermal conductivity in zone KZ.

DEL

25

W/m^2-K^4

Stefan-Boltzmann’s constant*emissivity. (See STEBOL, EMSF, and EMSC).

DGO

26

m

Initial grain size. Suggested value: 1.0E-05.

P0GAS

27

Pa

Initial plenum gas pressure at reference temperature TR.

XKRF (KZ)

28-34

W/m-K

Thermal conductivity of reflector for values of KZ not equal to KZPIN. XKRF(KZPIN) = thermal conductivity of cladding in the gas plenum region.

DENSS

35

Density of solid cladding at the reference temperature TR.

COOLDN

36

Not currently used.

RHOCSI (KZ)

37-43

J/m^3-K

Density * heat capacity for the inner structure.

RHOCSO (KZ)

44-50

J/m^3-K

Density * heat capacity for the outer structure.

RHOCR (KZ)

51-57

J/m^3-K

Density * heat capacity for the reflector. For KZ = KZPIN (the pin zone), RHOCR is for the cladding in the gas plenum.

RHOCG

58

J/m^3-K

Density * heat capacity for the gas in the gas plenum..

RG

59

m^2-K/W

Thermal resistance of plenum gas, typical value = 0.06.

FGMIN

60

Fraction of retained fission gas that assists non-equilibrium fission gas bubble induced fuel swelling (burnup dependent).

RST

61

Not currently used.

WRF

62

Not currently used.

RREF

63

Not currently used.

EMF

64

Not currently used.

EMS

65

Not currently used.

EMNA

66

Not currently used.

HMELT

67

Not currently used.

FCLOP

68

Fraction of open porosity that must be removed before axial movement allowed with metal fuels 0 ≤ FCLOP ≤ 1.

=0, Open porosity volume remains constant.

=1, All open porosity volume used before axial movement allowed.

TSEP1

69

K

Fuel plasticity temperature = TSEP1 + TSEP2 * (fuel-cladding interface pressure - plenum gas pressure). The fuel pellet annulus at this temperature does not move radially inward or outward during calculations of fuel mesh boundaries.

Suggested value: 2700 for oxide fuel.

TSEP2

70

K/Pa

Pressure adjustment to plasticity temperature.

Recommended value: 10^-8.

BONDNA

71

kg

Mass of sodium added to fuel pin to produce the fuel-cladding bond.

REFDEN

72

kg/m^3

Theoretical density of metal fuel at the reference temperature. Used for IFUELM = 2.

FUELEX

73

1/K

Fuel axial expansion coefficient. Used only with simple axial expansion feedback calculation. (See IAXEXP). Typical value: 1.1E-5.

CLADEX

74

1/K

Cladding axial expansion coefficient. Used only with simple axial expansion feedback calculation. (See IAXEXP). Typical value: 2E-5.

YFUEL

75

Pa

Fuel young’s modulus.

Typical value: 1.5E11.

Used with simple axial expansion and EBR-II feedback calculations.

YCLAD

76

Pa

Cladding Young’s modulus.

Typical value: 1.4E11.

Used with simple axial expansion and EBR-II feedback calculations.

FULREX

77

1/K

Fuel linear expansion coefficient for bond gap conductance calculation.

CLDREX

78

1/K

Cladding linear expansion coefficient for bond gap conductance calculation.

Note: FULREX and CLDREX are used only if ISSFU2 = -1 and IHGAP = 0.

EXPCFF

79

Effective axial expansion multiplier, for simple axial expansion feedback model only.

TTRANM

80

K

Transition temperature for determining the outer boundary of the middle fuel zone in the SSCOMP model for IFUELO = 1.

TTRANC

81

K

Transition temperature for determining the outer boundary of the central fuel zone in the SSCOMP model for IFUELO = 1.

HACHCH

82-89

Channel-to-channel (duct wall-to-duct wall) heat transfer coefficient x area per unit height. Used only if NCHCH > 0.

Note: Use the total duct wall contact area for all subassemblies involved.

POROSS

90

Porosity of the outer zone of metal fuel at the end of steady-state irradiation. Used in the SSCOMP model for IFUELO = 1. See also PORMSS and PORCSS.

PORMSS

91

Porosity of the middle zone of metal fuel at the end of steady-state irradiation. Used in the SSCOMP model for IFUELO = 1. See also POROSS and PORCSS.

PORCSS

92

Porosity of the central zone of metal fuel at the end of steady-state irradiation. Used in the SSCOMP model for IFUELO = 1. See also POROSS and PORMSS.

FPORNA

93-103

Ratio of sodium filled porosity to total porosity in the metal fuel by radial mesh node at the end of the pre-transient irradiation. Used in SSCOMP for IFUELO = 1.

TAUINV

104

1/s

Inverse of heat transfer time constant. Degree of implicitness, THETA2, is:

THETA2 = ( 1 + X )/( 2 + X )

X = DT * TAUINV

DT = time step size

Currently only used with the multiple pin option (JJMLTP not equal to 0).

Suggested value: 5.0 for metal fuel, 1.0 for oxide fuel.

FPIN-2 INPUT

XEUTHR

105

K

Eutectic threshold temperature (K).

Default value = 988.

(See FSPEC for consistent input).

XGBFRA

106

Not currently used.

XCLDHR (J)

107-130

Pre-transient hardness parameter used in cladding flow stress calculation. Default value is 0.223, the value appropriate to 20% CW un-irradiated stainless steel.

XFPLC0

131

Fuel power law creep constant C0.

XFPLC1

132

Fuel power law creep constant C1.

XFDVC0

133

Fuel power law swelling constant C0.

XFDVC1

134

Fuel power law swelling constant C1.

XCIPL0

135

Cladding idealized flow stress constant C0.

XCIPL1

136

Cladding idealized flow stress constant C1.

XHTERR

137

Relative convergence criterion for heat transfer calculation. Default value = 0.0005.

XEPSCA

138

Relative convergence criterion for cavity pressure. Default value = 0.001.

XEPSFE

139

Relative convergence criterion for finite element analysis. Default value = 0.0005.

XEPTES

140

Relative convergence criterion for plastic creep strains. Default value = 0.0005.

XEVTES

141

Relative convergence criterion for swelling strains. Default value = 0.0005.

END FPIN-2 INPUT

XMCFMC

142

Reserved by FED.

HACIFM

143

Reserved by FED.

HACOFM

144

Reserved by FED.

HAFMOP

145

Reserved by FED.

HAGPFM

146

Reserved by FED.

TOPLSS

147

Reserved by FED.

StructEX

148

1/K

Structure axial expansion coefficient. Used only with simple axial expansion feedback calculation. (See IAXEXP).

CDOSECONV

149

Conversion factor from clad fast neutron flux (n/cm²/s/1.0E+22) to dose rate (dpa/s).

Only applicable if IDEFOPT > 0 and ICTYPE = 4 (15-15Ti cladding).

COCOR

150

m

Clad outer corrosion thickness prior to transient initiation.

Only applicable if IDEFOPT > 0 and ICTYPE = 4 (15-15Ti cladding).

CDFMEAN

151

Mean value of the normal distribution, describing the predicted fraction of the fuel pins failed due to creep rupture as a function of Common Logarithm of CDF.

Only applicable if IDEFOPT > 0 and ICTYPE = 4 (15-15Ti cladding).

CDFSIGMA

152

Standard deviation value of the normal distribution describing the predicted fraction of the fuel pins failed due to creep rupture as a function of common logarithm of CDF.

Only applicable if IDEFOPT > 0 and ICTYPE = 4 (15-15Ti cladding).

DUMPCH

153-200

Not currently used.