Fluid Connectors - Incompressible

The Modelica By Example target code is:

connector Incompressible
    Modelica.SIunits.Pressure p;
    flow Modelica.SIunits.VolumeFlowRate q;
end Incompressible;

model IncompressibleContext
  IncompressibleContext _IncompressibleContext;
  model IncompressibleContext
    IncompressibleA a;
    IncompressibleB b;
  equation
    connect(a.io,b.io);
  end IncompressibleContext;
  model IncompressibleA
    VolumeFlowElement io;
  end IncompressibleA;
  model IncompressibleB
    VolumeFlowElement io;
  end IncompressibleB;

  connector VolumeFlowElement
    flow VolumeFlowRate q;
    Pressure p;
  end VolumeFlowElement;

  type VolumeFlowRate=Real(unit="m³/s");
  type Pressure=Real(unit="Pa");
end IncompressibleContext;

Note that in order to be a valid ConservedQuantityKind the Volume from the SysPhS library must in fact be incompressible volume, although this is not otherwise documented.