REFERENCE: A.5 Humidifier: Webel: ValueTypes and Units

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The diagram shows all ValueTypes and Units used in the Webel IT version of the Humidifier example, as gleaned using dimensional analysis (and yes this diagram is much larger than usually recommended):
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First, a big fat DISCLAIMER:
Note also that the Unit symbols (mostly) use Modelica-friendly syntax:

There is one Aussie-friendly exception: And a unit symbol "%" is introduced for percent.
The following are the keys to un-ravelling the units for the equations across the system: And yes, it took a while to figure that one out, as it's not at all obvious from the naming of the value properties and parameters in the spec version. Also:

The "vapor" is in fact handled with 3 different units in different parts of the system, denoted here VaporRate_mL_per_h, VaporRate_mL_per_s, and VaporRate_L_per_s, and we'll see it actually corresponds to the volume rate of the liquid water required to create the vapor (it is not a measure of steam volume).

The use of Integer as the base for FanPowerRatio (which is used in the system essentially as a 0/1 switch) is as a workaround for this:

To make the use of symbols and names more consistent - and to help tracing during dimensional analysis - this trail model uses either SysPhS versions of ValueTypes and Units, or introduces custom ones, although one could easily re-use ones from the ISO-80000 ModelLibrary where appropriate.


Make sure your custom ValueTypes either directly or indirectly extend Real:

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