6.1.6.1. XSDRNPM Data File Formats

As part of the development of the sensitivity capabilities in SCALE, the XSDRNPM module was modified to allow the writing of a new interface file containing information needed for sensitivity calculations. This same data file is used by TSUNAMI-1D. This information is written on unit NTD in the XSDRNPM input, when NTD is positive. When TSUNAMI-1D creates the inputs for the forward and adjoint XSDRNPM criticality calculations, NTD is set to 31 for the forward case and 32 for the adjoint case. The files written are ft31f001 and ft32f001, respectively.

6.1.6.2. XSDRNPM forward output file

For a forward case, XSDRNPM writes the following unformatted records on unit NTD:

RECORD 1: IZM,IM,MXX,MS,ISCT,MM,JT,IGM: IZM - Number of zones

IM - Number of spatial intervals

MXX - Number of compositions (mixtures)

MS - Length of the XSDRNPM mixing table

ISCT - Order of the Legendre scattering expansion

MM - Number of angles in the angular quadrature

JT - Number of flux moments

IGM - Number of energy groups

RECORD 2: IGE,IBL,IBR,ISN,IFTG,MMT,NT1,T: IGE - Geometry: 1/2/3 = plane/cylinder/sphere

IBL - Left-boundary condition: 0/1/2/3 = vacuum/reflected/periodic/white

IBR - Right-boundary condition

ISN - S_n quadrature order

IFTG - First thermal group

MMT - Number of neutron groups

NT1 - Unit number of working cross-section library

T - Problem title containing 80 characters

RECORD 3: V,R: V(IM) - Volumes of the spatial mesh cells (single-precision)

R(IM+1) - Boundaries of the spatial mesh cells (single-precision)

RECORD 4: W,PNC: W(MM) - Weights in the angular quadrature (single-precision)

PNC(MM,JT) - Scattering constants used to obtain flux moments from angular fluxes (single-precision)

RECORD 5: MA,MZ: MA(IM) - Zone number by interval

MZ(IZM) - Mixture number by zone

RECORD 6: MB,MC,XMD: MB(MS) - Mixture number in the cross-section mixing table

MC(MS) - Component (nuclide) in the cross-section mixing table

XMD(MS) - Atom density in the cross-section mixing table (single-precision)

RECORD 7: CHI,FISNU: CHI(IGM,MXX) - \(\chi\) for each mixture (single-precision)

FISNU(IGM,MXX) - \(\bar{v}\) times the fission cross section for each mixture (single-precision)

RECORD 8: EIGEN: EIGEN k_eff (single-precision)

NEXT IGM RECORDS: XNDC: XNDC(IM,MM) - Mesh cell centered angular flux for one group (double-precision)

LAST RECORD: TLEAKAGE: TLEAKAGE(IGM) - Total leakage from the system (single-precision)

6.1.6.3. XSDRNPM adjoint output file

For an adjoint case, XSDRNPM writes the following unformatted records on unit NTD, containing the following information:

RECORD 1: EIGEN: EIGEN - k_eff value (single-precision)

NEXT IGM RECORDS: XNDC: XNDC(IM,MM) - Mesh cell centered angular flux for one group (double-precision)

The adjoint angular fluxes are reversed in direction such that each angular flux is the importance for that direction in the forward case. This reversal is done by using the reflected angle. Also, the records are written in forward order such that the first record corresponds to the highest-energy group.