modelMoistAirInterface

Fluid interface that can be coupled to BCVTB for medium that model the air humidity

Extends from Buildings.Utilities.IO.BCVTB.BaseClasses.FluidInterface.

Information

This model allows interfacing to the Building Controls Virtual Test Bed an air-conditioning system that uses a medium model with water vapor concentration.

The model takes as input signals the temperature and water vapor concentration and, optionally, a bulk mass flow rate into or out of the system boundary. The state of the fluid that flows out of this model will be at this temperature and water vapor concentration. The output of this model are the sensible and latent heat exchanged across the system boundary.

When used with the BCVTB, a building simulation program such as EnergyPlus may compute the room air temperatures and room air humidity rate, which is then used as an input to this model. The sensible and latent heat flow rates may be sent to EnergyPlus to couple the air-conditioning system to the energy balance of the building model.

Note: The EnergyPlus building simulation program outputs the absolute humidity ratio in units of [kg/kg dry air]. Since Modelica.Media uses [kg/kg total mass of air], this quantity needs to be converted. The conversion can be done with the model Buildings.Utilities.Psychrometrics.ToTotalAir.

Components

TypeNameDefaultDescription
Modelica.Blocks.Interfaces.RealOutputHLat_flowLatent enthalpy flow rate, positive if flow into the component
Buildings.Fluid.Sensors.SensibleEnthalpyFlowRate[nPorts]senEntFloRatSensible enthalpy flow rates
Modelica.Blocks.Math.SumsumHSen_flowSum of sensible enthalpy flow rates
Modelica.Blocks.Math.FeedbackdiffDifference between total and sensible enthalpy flow rate
Modelica.Blocks.Interfaces.RealInputphiMedium relative humidity
Buildings.Utilities.Psychrometrics.X_pTphimasFraMass fraction

Revisions

  • May 1, 2013, by Michael Wetter:
    Removed the medium declaration in the instance of the model Buildings.Utilities.Psychrometrics.X_pTphi as this model no longer allows to replace the medium.
  • April 5, 2011, by Michael Wetter:
    Added nominal values that are needed by the sensor.
  • September 10, 2009, by Michael Wetter:
    First implementation.