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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 4.6.4 - Released 4/24/2024

  • Support was added for the Patch 9 version of TRACE
  • The Critical Heat Flux properties have been updated to support values 6 and 16.
  • MatLib Material library support was added to the Built-in Materials
  • Restart Cases in the TRACE plug-in have been updated to support negative Restart Number (DSTEP) values.
  • Added support for the WFSURF namelist variable for patch 9.
  • BWR Power components have been updated to support additional feedback tables.
  • Disabled USE_IAPWS_ST namelist option for Patch 9
  • Support was added for noncondensable gas number 8 - Non-ideal Helium
  • The symmetry column will be excluded from the Import PARCS Dialog if the TRACE code version is greater than or equal to V5.0 Patch 9.
  • An issue was resolved within the Multi Junction Edge Data dialog that caused the displayed junction index to be incorrect.
  • An issue was resolved within the Crossflow Connections dialog that did not support connecting to Fill and Break components.
  • An issue has been resolved that caused some properties within the diffmerge dialog to not appear within their attribute group.
  • An issue was resolved that resulted in the Single Junction calculated hydraulic diameter to be exported as 'Unknown' when the Single Junction is only connected to cross-flow connections.
  • An issue was resolved for exporting the Model Notebook Power Components that caused the exported value for the External Power property to say 'unsupported value'.< /li>
  • An issue was resolved when renodalizing a vessel component that caused the Tube Rows property to have 'Unknown' values even when the vessel had predefined Tube Rows values prior to renodalization. Issue 73
  • An issue was resolved that caused Heat Component Surface hydraulic cell references to be modified during vessel renodalization despite the original hydraulic cell not belonging to the vessel being renodalized.
  • An issue was resolved that caused the Gas Species and NC Mixture property within hydraulic components to be enabled when there are no values to modify.
  • As issue was resolved within the Power Component that caused the Powered Components diffmerge node to indicate there are differences when all of the powered components are the same.
  • An issue was resolved that caused Power Connections connected to Channels to have 'Unspecified' in the connection property view. This was updated to report the Channel or Heat Structure connected to the Power Component.