Model for a spray air washer with a prescribed outlet water vapor mass fraction in kg/kg total air.
This model forces the outlet water mass fraction at
port_b to be no lower than the input signal
X_wSet, subject to optional limits on the maximum
water vapor mass flow rate that is added, as described by the
parameter mWatMax_flow. By default, the model has
unlimited capacity.
The output signal mWat_flow ≥ 0 is the moisture
added to the medium if the flow rate is from port_a to
port_b. If the flow is reversed, then mWat_flow
= 0. The outlet specific enthalpy at port_b is
increased by the enthalpy of liquid water at 10°C times the
mass of water that was added. Therefore, the temperature of the
leaving fluid is below the inlet temperature.
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 model that uses a control signal u ∈ [0, 1] and multiplies this with the nominal water mass flow rate, use Buildings.Fluid.Humidifiers.Humidifier_u
This model only adds water vapor for the flow from
port_a to port_b. The water vapor of the
reverse flow is not affected by this model.
This model does not affect the enthalpy of the air. Therefore, if water is added, the temperature will decrease, e.g., the humidification is adiabatic.
enthalpyOfLiquid.