I am using the Modelica Buildings Library for a project and would like to know how to calculate the input parameter, 'nominal Heat Flow Rate,' that is required for several of the heat exchanger components i.e. the 'StratifiedEnhancedInternalHex' and the RadiatorEN442_2 models.
Is this 'rated value' something that is usually specified by the manufacture? I've searched several technical specifications and cannot find it listed. Or is this something you determine experimentally?
Or does this 'rated value' have to be modeled separately, using knowledge of the flow regime? As the model already requires input parameters such as pipe diameter, mass flow rate, pipe conductivity etc; why is this value not being calculated automatically in Modelica?
Sorry if I am missing something here, but if you could point me to a reference, I'd much appreciate it.