Modelica.Fluid.Interfaces.FluidPort_a

[XiongbaXu]

I developed a Modelica model, I want to link this model to other models, so I used the port, but I encounter a question, when I want to get the value of port.C_outflow, I always meet problems:Cannot resolve type of expression 1 - port_in.C_outflow. The operands have types Integer, Real[0] in component <NO_COMPONENT>.

[mwetter]

The error message

1 - port_in.C_outflow. The operands have types Integer, Real[0] 

likely comes from the situation that port_in.C_outflow is a vector of Reals of dimension 0, and that is subtracted from an integer (1).
You may want to look at Buildings.Fluid.Sensors.TraceSubstances for how to properly access trace substances.

[XiongbaXu]

Thank you. It is reasonable to use sensors, but when I tried sensors, I encountered another question.