modelEvaporatorCondenserWithCapacity
Extends from AixLib.Fluid.Interfaces.TwoPortHeatMassExchanger.
Information
Model for an evaporator or condenser with the use of a capacity to simulate heat losses.
Used in AixLib.Fluid.HeatPumps.ModularReversible.Modular and AixLib.Fluid.Chillers.ModularReversible.Modular, the heat flow to or from the volume is calculated in a black-box. Thus the heat is directly added to the medium.
Transient heat losses are modelled by adding a capacity
and two convection components to
AixLib.Fluid.Interfaces.TwoPortHeatMassExchanger.
One of the convection component is between the capacity and the volume
(with thermal conductance GInn) and the other between
the capacity and the ambient heat port (with GOut).
Implementation
Both GInn and GOut are constants
but declared without a parameter keyword so that
the calculation can follow a temperature or flow-rate based approach.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Boolean | isCon | =true for condenser, false for evaporator | |
| Heat losses | |||
| Boolean | use_cap | true | False if capacity and heat losses are neglected |
| Modelica.Units.SI.HeatCapacity | C | Capacity of heat exchanger, set to zero to ignore its dry mass | |
| Initialization › Capacity | |||
| Modelica.Units.SI.Temperature | TCap_start | Medium.T_default | Initial temperature of heat capacity |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.ThermalConductance | GOut | Exterior heat transfer coefficient, set to zero to ignore external heat loss but keep the dry mass | |
| Modelica.Blocks.Interfaces.RealOutput | GInn | Interior heat transfer coefficient | |
| Modelica.Thermal.HeatTransfer.Components.Convection | conIns | Convection between the wall and the working fluid | |
| Modelica.Thermal.HeatTransfer.Components.Convection | conOut | Convection and conduction between the wall and ambient air | |
| Modelica.Thermal.HeatTransfer.Components.HeatCapacitor | heaCap | Heat Capacity | |
| Modelica.Blocks.Sources.RealExpression | heaLosInt | Nominal heat loss coefficient to the interior | |
| Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a | port_out | Temperature and heat flow to the ambient | |
| Modelica.Blocks.Sources.RealExpression | heaLosExt | Nominal heat loss coefficient to the exterior | |
| Modelica.Thermal.HeatTransfer.Sources.PrescribedHeatFlow | preHea | Heat flow rate of the condenser | |
| Modelica.Blocks.Interfaces.RealInput | Q_flow | Heat flow rate from the refrigerant to the medium | |
| Modelica.Thermal.HeatTransfer.Sensors.TemperatureSensor | senT | Temperature sensor for the condenser volume | |
| Modelica.Blocks.Interfaces.RealOutput | T | Temperature of the condenser volume |
Revisions
-
November 26, 2018, by Fabian Wuellhorst:
First implementation (see issue AixLib #577)