FRAPCON-3.5 Enhancements

  1. Gaseous swelling model added. Described briefly in 2014 WRFPM slides. No new variables needed to activate
  2. Better error messages are added to output,
  3. Default values were matched to documentation
  4. Ability to model chamfers was added
  5. New variable: chmfrh, chamfer height (in,m), default value=0.0, must be between zero and half the pellet height.
  6. New variable: chmfrw, chamfer width (in,m), default value=0.0, must be between zero and the dish shoulder width.
  7. Ability to input variable axial nodes
  8. New variable: ivardm, flag to specify input of equal length axial nodes or variable length axial nodes. ivardm=0 specifies equal length axial nodes. ivardm=1 specifies variable length axial nodes. Default value is ivardm=0.
  9. If ivardm=1, input a value for deltaz(n) where n is the number of axial nodes. deltaz is the axial node length in ft or m depending on unit selection and the sum of all the deltaz values should be equal to totl.
  10. Extra outputs for the ARM statistical package were added
  11. The option to pick a name for FRAPTRAN restart file was added. If a restart files is selected add the following to the top of the input file:

FILE22='filename.restart',

STATUS='UNKNOWN', CARRIAGE CONTROL='LIST'

  1. Ability to input axial zoning of UO2-Gd2O3.
  2. To use a constant value of gadolinia concentration for all axial nodes, use same method from previous version and input gadoln=xx.
  3. To specify a different value of gadolinia concentration for each axial node, input gadoln(1)=xx, yy, …, zz for each axial node.
  4. Ability to input axial zoning of U-235
  5. To use a constant value of U-235 enrichment for all axial nodes, use same method from previous version and input enrchn=xx.
  6. To specify a different value of U-235 enrichment for each axial node, input enrch(1)=xx, yy, …, zz for each axial node.
  7. Ability to specify different axial nodes with different central hole radii, or no central hole
  8. To use a constant value of central hole radius for all axial nodes, use same method from previous version and input rc=xx.
  9. To specify a different value of central hole radius for each axial node, input rc(1)=xx, yy, …, zz for each axial node. (some nodes may be 0.0 and others may have a larger value)
  10. Increased time steps and axial nodes added
  11. 1000 time steps and 100 time dependent inputs possible for all tiem dependent variables
  12. im can be equal to any positive integer up to 1000
  13. p2(it)has a max number of inputs equal to 1000
  14. tw(it)has a max number of inputs equal to 1000
  15. go(it)has a max number of inputs equal to 1000
  16. ProblemTime(it)has a max number of inputs equal to 1000
  17. qmpy(it)has a max number of inputs equal to 1000
  18. 150 axial nodes, and 150 maximum number of inputs for axial variables
  19. na can be equal to 150
  20. crudmult(j-1) has a max number of inputs equal to 150
  21. flux(j) has a max number of inputs equal to 150
  22. x(n) and qf(n) are now dimensioned to 3344=152*22, which allows for 20 power shapes and 150 input pairs per shape (needs to be changed to 150 where it says maximum number of qf,x pairs is 40)
  23. xt(n) and cladt(n) are now dimensioned to 3344=152*22, which allows for 20 temperature profiles and 150 input pairs per profile (needs to be changed to 150 where it says maximum number of cladt,xt pairs is 40)
  24. 50 radial nodes for fuel, and 50 maximum number of inputs for radial variables
  25. nr can be equal to 50
  26. 50 radial nodes for gas
  27. Improved modeling of primary creep. Described in 2013 TopFuel paper. No new variable needed to activate.
  28. Change pickup fraction for ZIRLO from 12.5% to 17.5% based on recommendation from 2011 TopFuel meeting paper.
  29. Add option to model Optimized ZIRLO
  30. New Variable Defintion: icm=7 for Optimized ZIRLO
  31. Corrosion is 70% of ZIRLO based on data shown at 2013 ASTM conference and 2013 TopFuel conference.
  32. Other properties are the same as for ZIRLO based on claims made my Westinghouse.
  33. Add default values for roughf and roughc
  34. Default: roughf = 7.87e-5/2.0e-6 (in/m)
  35. Default: roughc = 1.97e-5/5.0e-7 (in/m)
  36. Change some labels in output file to better describe parameter being printed.
  37. A new relocation model was added in FRAPCON. No new input variable needed to activate.
  38. Added refabrication ability. See table below for new variables

Input Variables for Modeling Refabrication

Variable Name
(type) / Description / Units
British/SI / Limitations/Default Value
irefab
(I) / Time step to start using refabricated values / Dimensionless / Default = 10,000 (no refabrication)
nrefab1
(I) / Lower axial node for refabrication / Dimensionless
nrefab2
(I) / Upper axial node for refabrication / Dimensionless
cplrefab
(R) / Refabricated upper plenum length / in/m
vsrefab
(R) / Number of spring turns in refabricated upper plenum / Dimensionless
dspgrefab
(R) / New plenum spring coil diameter / in/m
dspgwrefab
(R) / New plenum spring wire diameter / in/m
fgpavrefab
(R) / Fill gas pressure at time step of refabrication / psi/MPa
airrefab
(R) / Fraction of air in refabricated rod / Fraction / Default = 0.0
n2refab
(R) / Fraction of nitrogen in refabricated rod / Fraction / Default = 0.0
arrefab
(R) / Fraction of argon in refabricated rod / Fraction / Default = 0.0
fgrefab
(R) / Fraction of fission gas in refabricated rod / Fraction / Default = 0.0
herefab
(R) / Fraction of helium in refabricated rod / Fraction / Default = 1.0
krrefab
(R) / Fraction of krypton in refabricated rod / Fraction / Default = 0.0
xerefab
(R) / Fraction of xenon in refabricated rod / Fraction / Default = 0.0

(R) = real, (I) = integer