modelDHWConsumption
DHW tank, HX, thermostatic mixing valve, and sink
Information
Model with fresh water station and domestic hot water load.
This model integrates a fresh water station, using Buildings.DHC.ETS.Combined.Subsystems.StorageTankWithExternalHeatExchanger with a domestic hot water load. The load is served at a specified temperature, using Buildings.DHC.Loads.HotWater.ThermostaticMixingValve to mix cold and hot water in order to meet the required hot water load.
The hot water load is specified through the input QReqHotWat_flow,
rather than the hot water mass flow rate, in order to take into account the actual
temperature of the hot water after the heat exchanger of the fresh water station.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Buildings.DHC.Loads.HotWater.Data.GenericDomesticHotWaterWithHeatExchanger | dat | Performance data | |
| Assumptions | |||
| Boolean | allowFlowReversal | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
| Nominal condition | |||
| Modelica.Units.SI.HeatFlowRate | QHotWat_flow_nominal | Nominal capacity of heat pump condenser for hot water production system (>=0) | |
| Modelica.Units.SI.TemperatureDifference | dT_nominal | Nominal temperature difference from the condenser | |
| Modelica.Units.SI.MassFlowRate | m_flow_nominal | QHotWat_flow_nominal/4200/dT_nominal | Nominal mass flow rate |
| Initialization | |||
| Medium.Temperature | T_start | Medium.T_default | Temperature start value of the tank |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Fluid.Interfaces.FluidPort_a | port_a | Fluid connector a (positive design flow direction is from port_a to port_b) | |
| Modelica.Fluid.Interfaces.FluidPort_b | port_b | Fluid connector b (positive design flow direction is from port_a to port_b) | |
| Buildings.Controls.OBC.CDL.Interfaces.RealInput | THotWatSupSet | Domestic hot water temperature set point for supply to fixtures | |
| Buildings.Controls.OBC.CDL.Interfaces.RealInput | TColWat | Cold water temperature | |
| Buildings.Controls.OBC.CDL.Interfaces.RealInput | QReqHotWat_flow | Service hot water load | |
| Modelica.Blocks.Interfaces.RealOutput | PEle | Electric power required for pumping equipment | |
| Buildings.Controls.OBC.CDL.Interfaces.BooleanOutput | charge | Output true if tank needs to be charged, false if it is sufficiently charged | |
| Buildings.Controls.OBC.CDL.Interfaces.RealOutput | TTanTop | Top temperature of tank | |
| Modelica.Blocks.Interfaces.RealOutput | dHFlo | Enthalpy flow rate |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Buildings.DHC.ETS.Combined.Subsystems.StorageTankWithExternalHeatExchanger | domHotWatTan | Storage tank with fresh water station | |
| Buildings.DHC.Loads.HotWater.ThermostaticMixingValve | theMixVal | Thermostatic mixing valve | |
| Buildings.Fluid.Sources.Boundary_pT | souDCW | Source for domestic cold water | |
| Buildings.DHC.ETS.BaseClasses.Junction | dcwSpl | Splitter for domestic cold water | |
| Buildings.Controls.OBC.CDL.Reals.MultiplyByParameter | gai | Gain to normalize hot water signal | |
| Modelica.Blocks.Sources.RealExpression | expTTanTop | Top temperature of tank | |
| Buildings.DHC.Networks.BaseClasses.DifferenceEnthalpyFlowRate | dHFlow | Enthalpy flow rate |
Contents
| Name | Description |
|---|---|
 Medium | Medium in the component |
Revisions
-
November 5, 2025, by Michael Wetter:
First implementation.