Recent News
SNAP Version 4.0.4 Released
July 7, 2022
AptPlot 8.0.1 Updated
April 29, 2022
PyPost 4.0.2 Released
July 7, 2022

TRACE Plug-in

The TRAC/RELAP Advanced Computational Engine (TRACE) code is the latest in a series of advanced, best-estimate reactor systems codes developed by the U.S. Nuclear Regulatory Commission for analyzing transient and steady-state neutronic-thermal-hydraulic behavior in light water reactors. It is the product of a long term effort to combine the capabilities of the NRC’s four main systems codes (TRAC-P, TRAC-B, RELAP5 and RAMONA) into one modernized computational tool.

The TRACE plug-in requires installation of the PARCS plug-in. Please note that the PARCS plug-in will automatically be selected for installation with the TRACE plug-in if you choose to install SNAP directly from the web site. If you download the installation packages to a folder for later installation, the TRACE plug-in will not be available for installation unless you include the PARCS plug-in in your download.

The TRACE Plug-in User's Manual provides instructions for working with TRACE models in SNAP. This Manual is also available as a searchable help set in SNAP.

Change Log

Version 4.5.1 - Released 7/5/2022:

  • The TRACE Plug-in has been updated to include model merge capabilities for the Radiation Enclosure and Power components.
  • An issue was resolved in which ASCII contexts for Radiation Enclosure Axial Level and Heat Levels were not editing the Radiation Enclosure component.
  • An issue was resolved in which edits for Radiation Enclosure Axial Level and Heat Levels were displaying the name 'null' when using the Edit->Undo/Redo menu items.
  • An issue has been resolved that would cause the TRACE retrieve initial conditions option has been to lose any modifications made to the ASCII restart file before reading from TPR under Windows. This includes modifications made by a parametric job stream, or pre-execution Python script. This issue did not occur when executing under Linux.
  • Material properties may now be defined using a SNAP table variable. Restart cases write placeholder data that will be resupplied at export or job submission time with the current table variable data.
  • An issue has been resolved which would prevent writing out the velocity scale factor values when graphically editing a restart case that resupplied a generalized state fill where the state table is provided by a table variable.
  • The TRACE Python Directed Job Stream samples were updated to use a CPython3 application instead of a Jython application.
  • The TRACE standpipe sample model was updated so that the y1, y2, and y3 numeric variables have initial values.
  • The vessel renodalization logic has been updated to ensure that leak path connections are modified to reflect the new renodalization.
  • The vessel renodalization logic has been updated to prevent an infinite loop when attempting to renodalize a vessel with unknown fluid state data.