modelSubstation_indirect_noStorage_L1

Simple model of a substation with indirect connection.

Information

1. Purpose of model

District heating Substation model without a storage based on mass flow calculation for constant dT.

2. Level of detail, physical effects considered, and physical insight

Ideal temperature difference assumed.

3. Limits of validity

(no remarks)

4. Interfaces

(no remarks)

5. Nomenclature

(no remarks)

6. Governing Equations

Based upon the calculation of necessary mass flow for a given temperature difference at heat demand.

7. Remarks for Usage

Due to the simple nature of the model, it is important to have a realistic supply temperature to avoid the return temperature to fall below possible values.

8. Validation

(no remarks)

9. References

(no remarks)

10. Version History

Model created by Philipp Huismann (huismann@gwi-essen.de), Oct 2018

Parameters

TypeNameDefaultDescription
SI.TemperatureT_startsimCenter.T_supplyTemperature at start of the simulation
SI.MassFlowRatem_flow_minsimCenter.m_flow_minMinimum mass flow rate to counteract possible zero massflow sitations, equals a simplified bypass

Connectors

TypeNameDefaultDescription
TransiEnt.Basics.Interfaces.Thermal.FluidPortOutwaterPortOut
TransiEnt.Basics.Interfaces.Thermal.FluidPortInwaterPortIn
Modelica.Blocks.Interfaces.RealInputQ_demand_RH
Modelica.Blocks.Interfaces.RealInputQ_demand_DHW

Components

TypeNameDefaultDescription
TransiEnt.SimCentersimCenter
TransiEnt.ModelStatisticsmodelStatistics
SI.TemperatureT_mixMixing temperature from room and domestic hot water
room_heating_hex_modelroom_heating_hex
dhw_heating_hex_modeldomestic_hot_water_hex
Modelica.Blocks.Math.GainsignChanger_2
ClaRa.Components.Sensors.SensorVLE_L1_TT_in_sub
Modelica.Blocks.Math.Addadd_supply
Modelica.Blocks.Math.Addadd_return
ClaRa.Components.BoundaryConditions.BoundaryVLE_Txim_flowm_flow_in
ClaRa.Components.BoundaryConditions.BoundaryVLE_Txim_flowm_flow_out
Modelica.Blocks.Math.GainsignChanger_1
ClaRa.Components.Sensors.SensorVLE_L1_TT_out_sub

Contents

NameDescription
room_heating_hex_model
dhw_heating_hex_model