Heat ports in component Buildings.Fluid.FixedResistances.BaseClasses.Pipe

[JordiGC-UPC]

Dear all,
Concerning the component Buildings.Fluid.FixedResistances.BaseClasses.Pipe, in the Documentation Browser it is said that this model can be used for modeling the heat exchange between the pipe and the environment. However there is no heat port to do so in the uppermost layer of the model. For this reason I modify this particular model to inherite correctly the heat ports of each of the mixing volumes for each segment in which the pipe is discretized. I inserted the component Modelica.Fluid.Interfaces.HeatPorts_a and made a connection of each of the heat ports of the mixing volumes with this component, within the code. In the equation block, instead of using the current code:

  connect(port_a, preDro.port_a);
  connect(preDro.port_b, vol[1].ports[1]);
  if nSeg > 1 then
    for i in 1:(nSeg - 1) loop
      connect(vol[i].ports[2], vol[i + 1].ports[1]);
    end for;
  end if;
  connect(vol[nSeg].ports[2], port_b)

I use this:

connect(port_a, preDro.port_a) ;
 connect(preDro.port_b, vol[1].ports[1]);
 connect(vol[1].heatPort,heatPorts_a[1]);
  if nSeg > 1 then
    for i in 1:(nSeg - 1) loop
      connect(vol[i].ports[2], vol[i + 1].ports[1]);
    end for;
    for i in 2:nSeg loop
      connect(vol[i].heatPort,heatPorts_a[i]);
      end for;
  end if;
  connect(vol[nSeg].ports[2], port_b)

So now I can use the heat port of the pipe to connect it to the ground.
Is this ok? Thanks for checking. If correct, I hope this might be useful to modify this component in future versions of the library.

p.s.: Sorry if I do not use proper programming terms.

[JayHuLBL]

@JordiGC-UPC Did you look into the model Buildings.Fluid.FixedResistances.Pipe and see how it is used in Buildings.Fluid.FixedResistances.Examples.Pipe?

[JordiGC-UPC]

Dear Jianjun,
Yes, I saw that the component Buildings.Fluid.FixedResistances.Pipe is doing what I expose above, but offering the possibility of either collect all the mixing voume heatports in one or not.
However, now I remember that when I face it for the first time I preferred to actuate on the BaseClass component to get a more customized modelt for my needs. For example, I prefer to specify externally and separatelly the thermal resistance due to the pipe wall material and the (optional) insulating layer.
Anyway, all is more clear now ;-)
Thanks!