This model outputs the entropy flow rate of the medium in the flow between fluid ports. The sensor is ideal, i.e., it does not influence the fluid.
If the parameter tau is non-zero, then the measured
specific entropy sout that is used to
compute the entropy flow rate
Ṡ = ṁ sout
is computed using a first order differential equation.
See
IBPSA.Fluid.Sensors.UsersGuide for an explanation.