modelVAVBranch
Supply branch of a VAV system
Information
Model for a VAV supply branch. The terminal VAV box has a pressure independent damper and a water reheat coil. The pressure independent damper model includes an idealized flow rate controller and requires a discharge air flow rate set-point (normalized to the nominal value) as a control signal.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.PressureDifference | dpFixed_nominal | 0 | Pressure drop of duct and other resistances that are in series |
| Modelica.Units.SI.MassFlowRate | m_flow_nominal | Mass flow rate of this thermal zone | |
| Modelica.Units.SI.Volume | VRoo | Room volume |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Buildings.Controls.OBC.CDL.Interfaces.RealInput | TRooHeaSet | Setpoint temperature for room for heating | |
| Buildings.Controls.OBC.CDL.Interfaces.RealInput | TRooCooSet | Setpoint temperature for room for cooling | |
| Modelica.Blocks.Interfaces.RealInput | TRoo | Measured room temperature | |
| Modelica.Fluid.Interfaces.FluidPort_a | port_a | Fluid connector a1 (positive design flow direction is from port_a1 to port_b1) | |
| Modelica.Fluid.Interfaces.FluidPort_a | port_b | Fluid connector b (positive design flow direction is from port_a1 to port_b1) | |
| Modelica.Blocks.Interfaces.RealOutput | yDam | Actual VAV damper position |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Fluid.Actuators.Dampers.PressureIndependent | vav | VAV box for room | |
| Buildings.Fluid.HeatExchangers.DryCoilEffectivenessNTU | terHea | Heat exchanger of terminal box | |
| Buildings.Fluid.Sources.Boundary_pT | sinTer | Sink for terminal box | |
| Buildings.Examples.VAVReheat.BaseClasses.Controls.RoomVAV | con | Room temperature controller | |
| Buildings.Fluid.Sensors.MassFlowRate | senMasFlo | Sensor for mass flow rate | |
| Modelica.Blocks.Math.Gain | fraMasFlo | Fraction of mass flow rate, relative to nominal flow | |
| Buildings.Fluid.Sensors.TemperatureTwoPort | TSup | Supply air temperature | |
| Modelica.Blocks.Math.Gain | ACH | Air change per hour | |
| Buildings.Fluid.Actuators.Valves.TwoWayLinear | valHea | Valve at reaheat coil | |
| Buildings.Fluid.Sources.Boundary_pT | souTer | Source for terminal box |
Contents
| Name | Description |
|---|---|
 MediumA | Medium model for air |
| MediumW | Medium model for water |
Revisions
-
February 25, 2021 by Baptiste Ravache:
Inverse the sign of terHea.Q_flow_nominal to respect the heat flow convention. -
June 6, 2017 by Jianjun Hu:
First implementation, based on Buildings library.