Transient Solver Advanced Parameters

The Transient Solver Advanced Parameters panel is located in the Miscellaneous group of Analysis Setup.

The options on this panel are intended for troubleshooting use and should only be changed with caution. In almost every model, the default values for these parameters is appropriate. There are rare circumstances where the user may wish to change them.

A description of some of the most commonly used advanced parameter options is provided here. For information and guidance on other options please contact AFT.

Create Transient Debug File - Disabled by default. When enabled, xStream will write relevant diagnostic information to a text file, including information on tolerance and convergence settings, records of when/if saturation conditions were reached, etc. The transient debug file will be created in the same location as the model file, and follows the naming structure "Model Name_#_GasTranDebug.txt", where Model Name is the user specified model name, and # represents a number assigned to differentiate between the transient debug files generated for different scenarios. It is recommended to send this file to AFT when requesting support on a model file.
Limit Properties to Saturation Conditions - Disabled by default. If enabled, xStream will attempt to limit the temperature and pressure to saturation conditions to allow the transient solution to continue. This will not produce accurate results as xStream cannot account for two-phase flow. However, this may be useful for troubleshooting purposes to be able to analyze the transient results up to the point that saturation conditions were reached.
Halt Solver When Saturation Conditions Encountered - Disabled by default. If enabled, xStream will halt the solver if the temperature and/or pressure conditions exceed the saturation line. This is useful to provide the user the chance to immediately stop the transient and troubleshoot the model, as any transient results calculated after the time that saturation conditions were reached will be invalid.