modelPartialHeater
BaseClass for heat exchangers in air handling units
Extends from Components.BaseClasses.PartialComponent (BaseClass for components in air handling units with one air flow).
Information
This partial model provides a idealized heat exchanger. The model considers the convective heat transfer from the heat transfer surface in the air stream. Moreover the heat capacity of the heating surface and the housing of the heat exchanger is considered.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Boolean | use_T_set | false | if true, a set temperature is used to calculate the necessary heat flow rate |
| Modelica.Units.SI.HeatFlowRate | Q_flow_nominal | 45E3 | maximum heat output of heater at design point. Only used, if use_T_set = true |
| Advanced | |||
| Modelica.Units.SI.SpecificHeatCapacity | cpAir (from PartialComponent) | 1006 | specific heat capacity of dry air |
| Modelica.Units.SI.SpecificHeatCapacity | cpSteam (from PartialComponent) | 1860 | specific heat capacity of steam |
| Modelica.Units.SI.Density | rhoAir (from PartialComponent) | 1.2 | Density of air |
| Nominal conditions | |||
| Modelica.Units.SI.MassFlowRate | m_flow_nominal (from PartialComponent) | nominal mass flow rate | |
| Modelica.Units.SI.PressureDifference | dp_nominal (from PartialComponent) | pressure drop at nominal mass flow rate | |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Blocks.Interfaces.RealInput | mAirIn_flow (from PartialComponent) | mass flow rate of incoming air | |
| Modelica.Blocks.Interfaces.RealInput | TAirIn (from PartialComponent) | Temperature of incoming air | |
| Modelica.Blocks.Interfaces.RealInput | XAirIn (from PartialComponent) | absolute humidity of incoming air | |
| Modelica.Blocks.Interfaces.RealOutput | mAirOut_flow (from PartialComponent) | mass flow rate of outgoing air | |
| Modelica.Blocks.Interfaces.RealOutput | TAirOut (from PartialComponent) | temperature of outgoing air | |
| Modelica.Blocks.Interfaces.RealOutput | XAirOut (from PartialComponent) | absolute humidity of outgoing air | |
| Modelica.Blocks.Interfaces.RealOutput | dp (from PartialComponent) | pressure difference | |
| Modelica.Blocks.Interfaces.RealInput | T_set | ||
| Modelica.Blocks.Interfaces.RealOutput | Q_flow | heat flow rate | |
| Modelica.Blocks.Interfaces.RealInput | u | input connector scaling heat flow rate [0..1] |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.SpecificEnthalpy | hAirIn (from PartialComponent) | specific enthalpy of incoming air | |
| Modelica.Units.SI.SpecificEnthalpy | hAirOut (from PartialComponent) | specific enthalpy of outgoing air | |
| PartialPressureDrop | partialPressureDrop |
Contents
| Name | Description |
|---|---|
| PartialPressureDrop |
Revisions
- April, 2019, by Martin Kremer:
First implementation. - August, 2019, by Martin Kremer:
Added possibility to use set temperature. - December, 2019, by Martin Kremer:
Removed internal PID. Output temperature is now directly set to set temperature.