Rename FourPort

[mwetter]

The model Annex60.Fluid.Interfaces.FourPort should be renamed to Annex60.Fluid.Interfaces.PartialFourPort and the following declarations should be removed

  parameter Modelica.SIunits.SpecificEnthalpy h_outflow_a1_start = Medium1.h_default 
    "Start value for enthalpy flowing out of port a1"
    annotation (Dialog(tab="Advanced", group="Initialization"));

  parameter Modelica.SIunits.SpecificEnthalpy h_outflow_b1_start = Medium1.h_default 
    "Start value for enthalpy flowing out of port b1"
    annotation (Dialog(tab="Advanced", group="Initialization"));

  parameter Modelica.SIunits.SpecificEnthalpy h_outflow_a2_start = Medium2.h_default 
    "Start value for enthalpy flowing out of port a2"
    annotation (Dialog(tab="Advanced", group="Initialization"));

  parameter Modelica.SIunits.SpecificEnthalpy h_outflow_b2_start = Medium2.h_default 
    "Start value for enthalpy flowing out of port b2"
    annotation (Dialog(tab="Advanced", group="Initialization"));

We should also check whether we want to add from PartialTwoPort the section

  // Model structure, e.g., used for visualization
protected 
  parameter Boolean port_a_exposesState = false 
    "= true if port_a exposes the state of a fluid volume";
  parameter Boolean port_b_exposesState = false 
    "= true if port_b.p exposes the state of a fluid volume";
  parameter Boolean showDesignFlowDirection = true 
    "= false to hide the arrow in the model icon";

These changes will make the models identical, except for the number of ports.

[bramvdh91]

I have made an implementation for this PartialFourPort based on the PartialTwoPort. I have duplicated the exposesState variables, but kept one showDesignFlowDirection (since I assume the flow in the two circuits will be equal but opposite). The component can be found in https://github.com/bramvdh91/modelica-annex60/tree/issue264_pipe (since I changed it working on issue 264) under Experimental.Pipe.BaseClasses.PartialFourPort.

[mwetter]

@bramvdh91 : Can you please move your model to Annex60.Fluid.Interfaces.PartialFourPort. This way, we can integrate it into the Annex 60 library and address this ticket separately from the pipe model. (It usually is easier to have smaller pull request as opposed to addressing multiple issues in one pull request.)

[bramvdh91]

I have added the component in a separate branch to limit the pull request.

[mwetter]

@bramvdh91 : Thanks for your pull request. I merged it to the development branch.

For now, I did not use exposesState as I don't think this is used by any model. I suggest to consider whether we should remove this parameter from all models, or else add it to the PartialFourPort and use it in models that extend from PartialFourPort. (Removing parameters is always harder as this can cause incompatibilities that require a major version update.)

I also revised your pull request to make the model identical to PartialTwoPort except for the changes that are needed because of having four ports.

I did not implement the showDesignFlowDirection flag as this is not used by other models. I made a new ticket to consider removing this in the two port models as well (#349).

Can you please check whether the version on the development branch issue299_partialfourport satisfies your need for the pipe model. You will however have to introduce the parameters

replaceable package Medium = Modelica.Media.Interfaces.PartialMedium
    "Medium in the component" annotation (choicesAllMatching=true);

  parameter Boolean allowFlowReversal=true
    "= true to allow flow reversal, false restricts to design direction (port_a -> port_b)"
    annotation (Dialog(tab="Assumptions"), Evaluate=true);

and assign them to allowFlowReversal1 and allowFlowReversal2, and also to Medium1 and Medium2.

[bramvdh91]

Okay, I think I misinterpreted the opening comment of this issue, which is why I didn't add the two media.