Model for an ideal heater that controls its outlet temperature to a prescribed outlet temperature.
This model forces the outlet temperature at port_b
to be
no lower than the temperature of the input signal
TSet
, subject to optional limits on the
capacity.
By default, the model has unlimited heating capacity.
The output signal Q_flow
is the heat added
to the medium if the mass flow rate is from port_a
to port_b
.
If the flow is reversed, then Q_flow=0
.
The outlet conditions at port_a
are not affected by this model,
other than for a possible pressure difference due to flow friction.
If the parameter energyDynamics
is different from
Modelica.Fluid.Types.Dynamics.SteadyState
,
the component models the dynamic response using a first order differential equation.
The time constant of the component is equal to the parameter tau
.
This time constant is adjusted based on the mass flow rate using
τeff = τ |ṁ| ⁄ ṁnom
where τeff is the effective time constant for the given mass flow rate ṁ and τ is the time constant at the nominal mass flow rate ṁnom. This type of dynamics is equal to the dynamics that a completely mixed control volume would have.
Optionally, this model can have a flow resistance.
Set dp_nominal = 0
to disable the flow friction calculation.
For a similar model that is a sensible cooling device, use BuildingSystems.Fluid.HeatExchangers.SensibleCooler_T. For a model that uses a control signal u ∈ [0, 1] and multiplies this with the nominal heating or cooling power, use BuildingSystems.Fluid.HeatExchangers.HeaterCooler_u
If the flow is from port_b
to port_a
,
then the enthalpy of the medium is not affected by this model.
The model has been validated against the analytical solution in the examples BuildingSystems.Fluid.HeatExchangers.Validation.PrescribedOutlet and BuildingSystems.Fluid.HeatExchangers.Validation.PrescribedOutlet_dynamic.