Release Notes

Version 5.2.1 (2848) - January 24, 2018

Bug Fixes

• `RESTART` files are not generated if `NSTEP = 0`, consistent with documentation. (#48)
• Eliminated a potential divide-by-zero error when the Young's Modulus for cladding and fuel are not provided in input. (#88)
• Corrected the declaration of a local variable used in debug print statements. (#91,#98)
• Corrected an issue where input parameter `IPRION` was not treated consistently when PRIMAR-4 was not being used. (#95)
• Eliminated a potential floating-point exception on Windows when debug prints are enabled. (#99)
• Eliminated a potential divide-by-zero error when predicting the time-step cutback in PRIMAR-4 if core channel flow rates are not changing. (#100)
• Corrected an issue where a non-zero value for `IFLOW` would impact PRIMAR-4 calculations. (#102)
• Eliminated a rare divide-by-zero error on Windows caused by poor CPU timing resolution. (#104)

Code Changes

• Removed unneeded compilation of `fpoptimizer` from the FParser library. (#81)
• Added support for "developer" build to simplify regression testing. (#85,#97)
• Updated copyright. (#86)
• Replaced non-standard calls to `ETIME` with calls to standard `CPU_TIME`. (#92)
• Corrected typos in the README file. (#94)

Version 5.2 (2568) - March 2017

New Features

• Control System models now have access to an extensive set of core and core channel state variables such as fuel, cladding, coolant, and structure temperatures; coolant flow rates and pressures; and several other parameters.

Bug Fixes

• All fixes from release 5.1.1 have been incorporated into 5.2

Code Changes

• Nearly all obsolete code constructs have been removed to bring the code into compliance with Fortran 2003 standards. (#82)
• Compiler options for Windows have been significantly revised for better consistency with macOS and Linux builds. (#79)
• `make source` now works on Linux (#83)

Version 5.1.1 (2524) - January 2017

Bug Fixes

• Corrected an issue in the input processor where integer input in a floating-point field would be interpreted with an assumed decimal point with five decimal digits. [2304],[2307]
• When input parsing fails in fixed-formatted input, a warning is printed if one or more tab characters was found. [2305]
• The `COMC` data structure is now fully initialized. (#69)
• Corrected an issue in the decay heat model where the 5^th^ decay heat region would not be properly initialized during steady state (#73)
• Corrected an array bounds violations error in the BOP module that produced different results depending on compilation options (#74)

Code Changes

• Removed unused character array processing routines (#61,#63,#64,#65,#66)
• SAS now reports errors if undefined element types or compressible volume types are detected in the PRIMAR4 input. (#68)

Version 5.1 (2238) - October 2015

New Features

• Full support for compiling on Mac OS X, Linux (x86), and Windows platforms.
• Consistent licensing mechanism across all three supported platforms.
• Support for user-defined input tables of arbitrary size.
• Support for user-defined input functions based on table lookup, scripted function, external plug-in, and control-system signals. Table lookup functions support linear, log-linear, spline, log-spline, and several other cubic interpolation options.
• Added binary "CONTROL.dat" file for logging control system signals during a simulation.
• Added conversion utility for reading "CONTROL.dat" file and generating Excel-compatible XML file.
• Input model files can now contain blank lines.
• Input files now require an explicit `ENDJOB` statement. Previously, a lone `-1` would qualify as an end-of-job indicator.
• Input blocks may be terminated by an `END` statement rather than specifying a data location of `-1`.
• Simulations that use the DIF3D-K Coupling Interface may specify radial, axial, and control-rod expansion models in SAS that are passed as additional feedback effects to the quasi-static solvers.
• Simulations that use the DIF3D-K Coupling Interface may include a Control System feedback model that will be passed as an additional feedback effect to the quasi-static solvers.
• Explicit control-rod motion may be specified in DIF3D-K Coupling Interface. Movable rod compositions are defined by new TABLE blocks and rod motions are defined by FUNCTION blocks.
• Initial steady-state flows in liquid segments in PRIMAR-4 may now be negative.
• Basic control system models that do not access PRIMAR-4 variables can be defined when only PRIMAR-1 is in use.
• The code now allows more than six delayed neutron precursor families in a `DLAYXS` file when `NPK > 1`.
• Extended interpretation of IPOBOI input to optionally terminate simulation when boiling is encountered.

Bug Fixes

• Corrected an issue where the acceleration pressure drop was not correctly evaluated for non-isothermal pipes.
• Corrected an issue with a missing `USE` declaration that led to a regression failure in an FPIN model.
• A lone `-1` in input is no longer interpreted as an end-of-job marker.
• Channel-dependent input arrays are now properly initialized and do not depend on compiler settings or relying on users to zero a block on first use.
• Corrected an issue in the DIF3D-K coupling interface where a lower fission gas plenum (IPLUC ≠ 0) was not handled properly.
• Issues with reading a restart file with multiple restart frames have been resolved.
• Corrected an array bounds violation that could result in improper null transient initialization with table lookup steam generators.
• Upper reflector temperatures are now printed correctly by the boiling module.
• Resolved an issue where job titles were mangled by the DIF3D-K output routines.
• Corrected a memory issue that occurred when a file-wide chi vector is not present in an ISOTXS file.

Code Changes

• Added distribution target builds to include licensing pre-flight checks in executable.
• Renamed GEOMIN common block in fpin to "FPGEOMIN" to avoid naming conflicts with original GEOMIN input block.
• Eliminated some code structures that led to optimization failures with the Intel 2013 compiler.
• All source code is now declared with `IMPLICIT NONE`.
• The `COMC` common block has been completely rewritten as two new modules.
• The `COLC` common block has been completely rewritten and merged into one of the new modules for `COMC`.
• The `PLUC` common block has been completely rewritten as a new module.
• Internal data structures for DEFORM-4 and DEFORM-5 have been completely rewritten as new modules.
• The common blocks for `ANEUTR`, `INEUTR`, and `RNEUTR` have been rewritten as new modules.
• Implemented significant refactoring of the DIF3D-K Coupling Interface to extract the transient driver as a separate source file.
• Eliminated legacy timers and checks on remaining CPU time that weren't enforced anyway.
• Source code has been improved to be more compliant with pre-processor requirements.
• Added an internal `sleep` function where the argument is interpreted in milliseconds.
• Added `svn:keywords` property on files that were missing the setting.
• Corrected some minor issues where dummy arguments were not declared with the correct shape.
• Debug build target now implements more aggressive checking for uninitialized variables. Some previously uninitialized variables are now properly initialized.
• The Control System module has been significantly refactored and is no longer dependent on PRIMAR-4 to operate.
• All FPIN code has been converted to free-format source style.
• Full source can be optionally compiled to produce "Mini SAS", which excludes severe accident and balance-of-plant modules and limits models to five channels.