General Release info:

Control Valves: Improved consistency of calculated valve position and valve coefficient over the complete operating range.

Polyethylene pipes, new pipe sizes added.

Petroleum fraction properties, NBP050 to NPB450 range added to fluids database.


  • Added back a directional definition for all flow control valves. This requires the user to specify the flow direction through the valve and is necessary to reduce interaction between flow control valves in large networks
  • Removed Text Import and Export menu options because format is now out of date and is not supported in the future.


  • Multiple flow controllers in a network could occasionally cause convergence BEFORE the network has actually converged. See changes above.
  • Liquid line with heat transfer in buried pipes, sometimes calculated out phase state as two-phase when phase state should be liquid.
  • Pipe scaling was not read in properly from old files (pre V3.30).