Select the inner channel (line P1-P3), right-click and select Properties. Click Yes to the Assign new property? prompt.
Click New and select Channel.
""""Enter 0 for the Channel heat transfer effectiveness (HTE). """"
In the Name box, enter an appropriate name for the channel property, then click OK twice.
Select the outer channel (P1-P2), right-click and select Properties. Click Yes to the Assign new property? prompt.
Click New and select Bubbler.
""""Enter 1 for the Channel heat transfer effectiveness (HTE). """""