User manual

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• New pre heater model, ThermalPower.TwoPhase.Condensers.Condenser_3_zones.
The 3-zones make it possible to simulate sub-cool and super-heat effects.
• New parameter in Benson separator that specifies the outlet vapor quality.
• Fixed mass conservation in ThermalPower.TwoPhase.FlowChannels.Pipe_lumpedP
(valid for positive flow), the conservation laws were not fulfilled during transients.
Note that there might be a minor difference in dynamics compared to result using
older versions.
• More efficient implementation of two-phase lumped pipe, better simulation
performance.
• More efficient implementation of gas lumped pipe, better simulation performance.
• Improved Modelica compliance.
Models using Thermal Power version 1.8 will automatically be converted to version 1.9
when loaded in Dymola.
3.6.16 Vapor Cycle Library
A new version 1.2 of the Vapor Cycle Library is available.
New features
• A static reversible valve, which can be used in architectures that change operation
mode.
• A turbine model parametrized with a mass flow lookup table and an efficiency look up
table.
• A compressor model with a parametrisation suitable for dynamic compressors. It is
parametrised with an isentropic efficiency table and a mass flow table.
• An ORC example experiment has been added to the library
• A bend component has been added to the library.
• A counterflow internal heat exchanger has been added to the library.
• Visualizers for all working fluids have been added to the library.
• The library contains a new User's Guide and two Tutorials.
Examples of improvements
• Turbine or the compressor face correct inlet density also for two-phase inlet now. The
default characteristics however do not take into account performance deterioration
because of liquid at the inlet.
• All heat transfer correlations and pressure drop correlations for pipes have been moved
in order to improve user friendliness when working with a combination of different
Modelon libraries. Their description and information is updated. Running the included
conversion script is necessary for this update.
• The default two phase medium model has been changed from R134a, reference
properties by Tillner-Roth to R134a, short form Helmholtz EOS by Span. Its accuracy
is slightly lower but still more than sufficient for most applications. The simulation
speed is increased significantly with the simpler model.