Vapor Cycle Library v2.3 is part of Modelon’s 2019.1 release.

New versions of Modelon libraries are sold and distributed directly from Modelon, as well as approved resellers.

New Features

  • New implementation in the AirChannels to compute the pressure drop and HeatTransfer based on average fluid properties (i.e., non-isothermal) as an option. Refer to Correlation based on averaged properties user guide for more information.
  • New correlation used for transport properties of R1234yf. More information can be found in the documentation.
  • Media properties for R134a and R1234yf using spline-based table lookup (SBTL) are now available in the media package. For more details, see SBTL.


  • Improved robustness for two-phase mediums. This fixed previous issues where NaN could occur as output in two-phase medium property calculations.
  • Fixed incorrect direction of summary variable Q_flow for VaporCycle.HeatExchangers.TwoPhaseTwoPhase. Added Q_flow_sec for secondary side heat flow. Note: conversion scripts will modify models to maintain backward compatibility.

Conversion of user libraries

  • User libraries will automatically be converted from version 2.2. These conversions are made using the included conversion script: VaporCycle/Resources/Scripts/Convert_to_2.3.mos.


  • Vapor Cycle 2.3 is based on the Modelon Base Library 3.3 and Modelica Standard Library 3.2.2. It can be combined with Liquid Cooling Library 2.3 and Heat Exchanger Library 2.3.