The Vapor Cycle Library, or the VCL, is intended for the steady-state and dynamic analysis of vapor compression cycles. Typical tasks are component selection, system performance optimization and verification and also control design and verification. The library can be used to analyze partial as well as complete cycles. Models are designed in a way that is similar to the structure of real thermodynamic cycle assemblies.
Modeling and simulation
Many simulation tools are essentially user-interfaces for setting the parameters of fixed simulation models. This means that the actual equations that describe the model are impossible, or difficult, to modify by users. This Modelon modelica library offers a different approach and provides much more flexibility. In combination with a simulation tool this Modelon library is a complete modeling and simulation tool. This is important to understand, since it implies that the working procedure is slightly different and contains some additional steps:
- Build models that describe the phenomena of interest,
- Tune the model parameters,
- Use the models to set up an experiment that exposes the phenomena of interest,
- Simulate the experiment,
- Analyze the results
This Modelon library contains a large set of pre-defined models and templates that makes most modeling tasks straightforward. For many standard tasks it is possible to use the library in the same way as a pure simulation tool, i.e. it is sufficient to choose the right model, define all parameters and start the simulation.
Flexibility with prudence
It is possible for users to modify and extend most of the models in the library, and also to complement the library with custom models. It is also possible to mix with model components from other libraries. This is one of the major benefits of describing models using a high-level modeling language like Modelica. Customization of models and components can be done either from the graphical user interface and diagram view, or, for advanced users, by typing Modelica source code. There is also great flexibility in setting up experiments and analyzing results. The flexibility implies great freedom for users to define models and experiments, but may also require more attention to details and understanding.
All Modelon libraries are compatible and can be combined to solve specific engineering design tasks. Two libraries of Modelon are of particular interest for the Vapor Cycle library: the Heat Exchanger library and the Liquid Cooling library. The Heat Exchanger library contains detailed models of heat exchangers and permits stacking. The Liquid Cooling library on the other hand is designed for modeling of coolant circuits. Please note that both these libraries can also be used as a stand alone solution.