Version 3.33 is primarily a maintenance release addressing reported bugs and adding new features requested by our users. It is recommended that all users upgrade to this release.

We have added the ability to make buried pipe heat loss calculations. To support this calculation, different pipe coatings, soil, and backfill types have been added to the Insulation database. In addition, the thermal conductivity as a function of temperature relationship for all insulation materials and soils has been improved.

For gases flowing at or near the saturation point in pipes with heat loss on, we have added an option to include condensate traps. If this option is “on”, the flow will stay in the gas phase at the saturation point and the software will report the mass of condensate to be removed. By default, this option is “off”, and so some of the gas will condense and become two-phase as it flows down the pipe. This means the vapor quality decreases along the flowpath because the condensate is not removed.


  • Added the ability to make a buried pipe calculation. Added different pipe coating, soil, and backfill types to the insulation database.
  • Added phosphine gas to physical property database.
  • Improved insulation thermal conductivity as a function of temperature relationship and added more data for insulation materials.
  • Added the ability to assume steam traps are present for a condensing gas. This option (‘Options | Calculation…’ menu item; Gas page) prevents gasflow from developing into 2-phase flow when heat loss is included.
  • Bill of Materials now subdivides pipes into schedules.
  • Added ability to model expansion loops in one component, instead of drawing out each individual expansion loop.
  • Added more calculation examples to QA tests and updated help file.


  • For Open Pipes and Open Boundaries with a resistance, the exit static pressure is now assumed to be atmospheric pressure. In earlier releases, the exit stagnation pressure was assumed to be atmospheric.
  • Restricted tee junction K values to maximum and minimum values: Max = 90 and Min = -15. This aids convergence without limiting practical values.
  • Added the ability to include Joule Thomson Coefficient in “Do Heat Loss Calculation”, via the ‘Options | Calculation…’ menu item; Gas page.