Fluids & Co and PASS Team Announce Release of PASS/HYDROSYSTEM 4.5

Fluids & Co and PASS Team are pleased to announce release of a new PASS/HYDROSYSTEM version. The software combines sophisticated calculation capabilities to deliver fluid flow and heat transfer simulation and sizing of piping networks.

A lot of significant enhancements

PASS/HYDROSYSTEM 4.5 includes a lot of significant enhancements. Among the most important of them are the following ones:


1. Slug flow parameters (size, frequency, speed of slugs, etc.) for gas-liquid flow can now be calculated and reported using TUFFP Unified model. Forces in elbows and flow-turns caused by gas-liquid slug flow are now calculated and can be exported to PASS/START-PROF software for accounting them in piping stress analysis.

2. We made several improvements to the calculation of gas-liquid flow using the TUFFP methods:

  1. improvement of the two-phase flow pattern map output for this model;
  2. you may more accurately display severe slugging pattern on the flow pattern map;
  3. use of the latest (2021) version of the TUFFP Unified model libraries for gas-liquid flow calculation.

3. Selecting methods for two-phase flow calculation becomes easier – now along with loading the XML file with calculation settings, one can select a ′typical′ two-phase flow calculation profile from the list.

4. We made improvements to the calculation of ′settling slurry′ flow:

  1. addition of solid phase correction for the centrifugal pumps performance curves;
  2. improvement of the algorithm for determining the flow pattern of liquid-solid mixtures at very low flow rates .

Thermal calculation

5. Added the thermal calculation of underwater pipelines.

6. We also made some improvements to the thermal analysis of pipelines, including more accurate calculation of ′internal′ heat transfer coefficient; improved heat transfer analysis for fittings, bends and other elements of the pipeline; more accurate thermal analysis in the rare case of gas laminar flow.

7. We added the insulation materials database (with materials according to ASTM standards) to the program to allow a user both entering materials properties manually and to select insulation and cover materials from the database.

Graphical consideration

8. It is now enable to work with ′disconnected′ piping systems (consisting of two or more fragments physically not connected to each other). Possible import of disconnected pipelines from PCF or PASS/START-PROF files. We now have a new ′Connect nodes′ function that connects any two pipeline nodes with a branch, containing a pipe section (automatic calculation of the length and direction of the section). This function is very useful for connecting of disconnected fragments in a pipeline.

9. We added piping model export to PCF files (you may now use these files for import into other 3D modeling systems and/or for generation of isometric drawings). We also made several improvements to the PCF files import, including import of equipment and elements names.

10. Piping element selection on piping diagram now has a new feature: by right-clicking on a component/node/etc. one can select not only the element itself, but also the branch/fragment of the pipeline it belongs to.

Other improvements include updated versions of import modules from AVEVA PDMS, E3D and MARINE, and embedded Combit List & Label report generator; as well as some improvements of the calculation speed of GERG-2008 thermodynamic library.

Visit the Knowledge Base to learn more about PASS/HYDROSYSTEM 4.5 capabilities!

All users with active Maintenance Support are recommended to download the new software version.

For more details, contact us.