modelGenericAHU
Generic air-handling unit with heat recovery system
Information
The GenericAHU is an air-handling unit model with detailed hydraulic system of the preheater, heater and cooler. The ahu includes a heat exchanger for heat recovery and a humidifier for the supply air. The humidifier can be insert steam or water that evaporates completely (adiabatic). Further, the ahu includes an adiabatic humidifier in the return air chanal in order to cool the return air and use the heat recovery heat excahnger to cool the supply air. The preheater, steam humdifier and adiabatic humidifier are conditional and can be deactivated.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.Temperature | T_amb | Ambient temperature | |
| Modelica.Units.SI.MassFlowRate | m1_flow_nominal | 1 | Nominal mass flow rate in air canal |
| Modelica.Units.SI.MassFlowRate | m2_flow_nominal | 0.5 | Nominal mass flow rate in hydraulics |
| Modelica.Units.SI.PressureDifference | dpDamper_nominal | 1 | Pressure drop of fully open dampers at nominal mass flow rate |
| Advanced | |||
| Modelica.Units.SI.Time | tau | 15 | Time Constant for PT1 behavior of temperature sensors |
| Dynamics › Equations | |||
| Modelica.Fluid.Types.Dynamics | energyDynamics | Modelica.Fluid.Types.Dynamics.DynamicFreeInitial | Type of energy balance: dynamic (3 initialization options) or steady state |
| Modelica.Fluid.Types.Dynamics | massDynamics | Modelica.Fluid.Types.Dynamics.DynamicFreeInitial | Type of mass balance: dynamic (3 initialization options) or steady state |
| Fans | |||
| Fluid.Movers.BaseClasses.Characteristics.efficiencyParameters | hydraulicEfficiency | Hydraulic efficiency of the fans | |
| Advanced › Initialization | |||
| Modelica.Units.SI.Temperature | T_start | 303.15 | Initialization temperature |
| Preheater | |||
| Boolean | usePreheater | true | If true, a preaheater is used |
| Humidifiers | |||
| Boolean | useHumidifierRet | true | If true, a humidifier in return canal is used |
| Boolean | useHumidifier | true | If true, a humidifier in supply canal is used |
| Assumptions | |||
| Boolean | allowFlowReversal1 | true | = false to simplify equations, assuming, but not enforcing, no flow reversal for medium in air canal |
| Boolean | allowFlowReversal2 | true | = false to simplify equations, assuming, but not enforcing, no flow reversal for medium in hydraulics |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Fluid.Interfaces.FluidPort_a | port_a1 | Fluid connector a1 (positive design flow direction is from port_a1 to port_b1) | |
| Modelica.Fluid.Interfaces.FluidPort_b | port_b1 | Fluid connector b1 (positive design flow direction is from port_a1 to port_b1) | |
| Modelica.Fluid.Interfaces.FluidPort_a | port_a2 | Fluid connector a2 (positive design flow direction is from port_a2 to port_b2) | |
| Modelica.Fluid.Interfaces.FluidPort_b | port_b2 | Fluid connector b2 (positive design flow direction is from port_a2 to port_b2) | |
| Modelica.Fluid.Interfaces.FluidPort_a | port_a3 | Fluid connector a3 (positive design flow direction is from port_a3 to port_b3) | |
| Modelica.Fluid.Interfaces.FluidPort_b | port_b3 | Fluid connector b3 (positive design flow direction is from port_a3 to port_b3) | |
| Modelica.Fluid.Interfaces.FluidPort_a | port_a4 | Fluid connector a2 (positive design flow direction is from port_a2 to port_b2) | |
| Modelica.Fluid.Interfaces.FluidPort_b | port_b4 | Fluid connector b2 (positive design flow direction is from port_a2 to port_b2) | |
| Modelica.Fluid.Interfaces.FluidPort_a | port_a5 | Fluid connector a2 (positive design flow direction is from port_a2 to port_b2) | |
| Modelica.Fluid.Interfaces.FluidPort_b | port_b5 | Fluid connector b2 (positive design flow direction is from port_a2 to port_b2) | |
| BaseClasses.GenericAHUBus | genericAHUBus | Bus connector for generic ahu |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| RegisterModule | preheater | Preheating coil subsystem | |
| RegisterModule | cooler | Cooling coil subsystem | |
| RegisterModule | heater | Heating coil subsystem | |
| Fluid.HeatExchangers.DynamicHX | dynamicHX | Heat recovery heat exchanger | |
| Fluid.Actuators.Dampers.Exponential | flapSup | Supply air flap | |
| Fluid.Actuators.Dampers.Exponential | flapRet | Return air flap | |
| Fluid.Actuators.Dampers.Exponential | dampHX | Flap to heat recovery system | |
| Fluid.Actuators.Dampers.Exponential | dampBypass | Bypass flap of heat recovery system | |
| Modelica.Blocks.Sources.Constant | const | ||
| Modelica.Blocks.Math.Add | add | ||
| Fluid.Movers.FlowControlled_dp | fanSup | Supply air fan | |
| Fluid.Movers.FlowControlled_dp | fanRet | Return air fan | |
| Fluid.Humidifiers.GenericHumidifier_u | humidifier | Steam or adiabatic humdifier in supply canal | |
| Fluid.Humidifiers.GenericHumidifier_u | humidifierRet | Adiabatic humidifier in retrun canal: cools inlet air of heat recovery system | |
| Fluid.Sensors.TemperatureTwoPort | senTRet | Return air temperature sensor | |
| Fluid.Sensors.TemperatureTwoPort | senTExh | Exhaust air temperature sensor | |
| Fluid.Sensors.TemperatureTwoPort | senTSup | Supply air temperature sensor | |
| Fluid.Sensors.TemperatureTwoPort | senTOda | Outside air temperature sensor | |
| Fluid.Sensors.VolumeFlowRate | senVolFlo | Exhaust volume flow sensor | |
| Fluid.Sensors.RelativeHumidityTwoPort | senRelHumSup | Supply air humidity sensor | |
| Fluid.Sensors.RelativeHumidityTwoPort | senRelHumSup1 | Return air humidity sensor | |
| Fluid.Interfaces.PassThroughMedium | passThroughPreheater | Passthrough if without preheater | |
| Fluid.Interfaces.PassThroughMedium | passThroughHumidifer | Passthrough if without humidifier | |
| Fluid.Interfaces.PassThroughMedium | passThroughHumidiferRet | Passthough if without adiabtic return air humidifier |
Contents
| Name | Description |
|---|---|
 Medium1 | Medium in air canal in the component |
| Medium2 | Medium in hydraulic circuits |
Revisions
- October 29, 2019, by Alexander Kümpel:
First implementation