modelHeatflow_L2
Extends from TransiEnt.Components.Boundaries.Heat.Base.PartialHeatBoundary.
Information
Purpose of model
A model of a heat boundary with a L2 heat exchanger from the ClaRa Library and a generic valve from the ClaRa Library. Both component models are documented in the ClaRa Library. The heat flow can be set constant or can be set via an input. The valve is used to
Level of detail, physical effects considered, and physical insight
L2 (defined in the CodingConventions)
- consideration of a pressure loss according to a chosen pressure loss model
- dynamic mass and energy balance inside the heat exchanger model
- consideration of variable fluid properties
Interfaces
FluidPortIn
FluidPortOut
RealInput (for specification of boundary power)
Validation
The model was tested here:
TransiEnt.Components.Boundaries.Heat.Check.Test_Heatflow_L2
References
The heat exchanger model and the valve model are from the ClaRa Library.
Version History
Model created by Arne Koeppen / Lisa Andresen (andresen@tuhh.de), Jul 2013
Refactoring after new boundary / consumer concept by Pascal Dubucq (dubucq@tuhh.de) on Mon Aug 18 2014
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| TILMedia.VLEFluidTypes.BaseVLEFluid | Medium (from PartialHeatBoundary) | simCenter.fluid1 | Medium model |
| SI.Power | Q_flow_n | 100e3 | |Heat demand|Nominal heating power |
| Boolean | use_Q_flow_in | true | |Heat demand|Use external value for Q_flow |
| Boolean | change_sign | false | Change sign on input value (false: setpoint < 0 means producing heat) |
| SI.Power | Q_flow_const | 100e3 | |Heat demand|Constant heating power |
| SI.MassFlowRate | m_flow_nom | simCenter.m_flow_nom | |Heat exchanger|Nominal mass flow rate |
| ClaRa.Basics.Units.EnthalpyMassSpecific | h_nom | 1e5 | |Heat exchanger|Nominal specific enthalpy |
| SI.HeatCapacity | C | 1e9 | |Heat exchanger|Heat capacity (geometry is calculated by this value) |
| SI.Temperature | T_start | 323.15 | |Heat exchanger|Initial temperature |
| Integer | initOption | 0 | |Heat exchanger|Type of initialisation |
| Real | valveAuthority | 0.6 | |Valve|Valve authority |
| SI.Pressure | Delta_p_nom | simCenter.p_nom[2] - simCenter.p_nom[1] | |Valve|Nominal pressure drop |
| Heat exchanger | |||
| SI.Pressure | p_nom | simCenter.p_nom[1] | Nominal pressure |
| SI.Pressure | p_start | simCenter.p_nom[1] | Start value of system pressure |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| TransiEnt.Basics.Interfaces.Thermal.FluidPortOut | fluidPortOut (from PartialHeatBoundary) | ||
| TransiEnt.Basics.Interfaces.Thermal.FluidPortIn | fluidPortIn (from PartialHeatBoundary) | ||
| TransiEnt.Basics.Interfaces.Thermal.HeatFlowRateIn | Q_flow_prescribed | RealInput (for specification of boundary power) |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| TransiEnt.SimCenter | simCenter (from PartialHeatBoundary) | ||
| Modelica.Units.SI.HeatFlowRate | Q_flow_boundary (from PartialHeatBoundary) | fluidPortIn.m_flow*(actualStream(fluidPortIn.h_outflow) - actualStream(fluidPortOut.h_outflow)) | |
| ClaRa.Components.HeatExchangers.IdealShell_L2 | heatExchanger | ||
| Modelica.Thermal.HeatTransfer.Sources.PrescribedHeatFlow | heatDemand | ||
| ClaRa.Components.VolumesValvesFittings.Valves.GenericValveVLE_L1 | controlValve | ||
| Modelica.Blocks.Math.Gain | normalizer | ||
| Modelica.Blocks.Math.Gain | signChanger |
Contents
| Name | Description |
|---|---|
 PressureLoss |