refactor pressureDrop coefficient to dp_nominal in PartialHeatGenerator

[DaJansenGit]

What is the problem?

Currently the PartialHeatGenerator model uses the following equation to calculate the dp_nominal variable:

dp_nominal=m_flow_nominal^2*a/(rho_default^2)

with a being the pressureDrop coefficient. As this coefficient is only a relict of the Modelica.Fluid.Fittings.GenericResistances.VolumeFlowRate model which is not used anymore, we want to get rid of it.

How do we want to solve it?

• Remove the default equation from PartialHeatGenerator
• Refactor all records as they provide the pressure coefficient currently (but only because it was needed for the former model approach and not because the data sheets provided it).
  • calculation to calculate dp_nominal from a: dp_nominal = m_flow_nominal^2*a/(rho_default^2)