modelCoolingAndHeating
Active beam unit for heating and cooling
Extends from IBPSA.Fluid.HeatExchangers.ActiveBeams.Cooling (Active beam unit for cooling).
Information
This model is identical to IBPSA.Fluid.HeatExchangers.ActiveBeams.Cooling, except that an additional water stream and convector is added to allow for heating in addition to cooling.
For a description of the equations, see the User's Guide.
Performance data are available from IBPSA.Fluid.HeatExchangers.ActiveBeams.Data.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Integer | nBeams (from Cooling) | 1 | Number of beams in parallel |
| Nominal condition | |||
| Data.Generic | perCoo (from Cooling) | Performance data for cooling | |
| Data.Generic | perHea | Performance data for heating | |
| Assumptions | |||
| Boolean | allowFlowReversalWat (from Cooling) | true | = true to allow flow reversal in water circuit, false restricts to design direction (port_a -> port_b) |
| Boolean | allowFlowReversalAir (from Cooling) | true | = true to allow flow reversal in air circuit, false restricts to design direction (port_a -> port_b) |
| Dynamics › Nominal condition | |||
| Modelica.SIunits.Time | tau (from Cooling) | 30 | Time constant at nominal flow (if energyDynamics <> SteadyState) |
| Flow resistance | |||
| Boolean | from_dpWat (from Cooling) | false | = true, use m_flow = f(dp) else dp = f(m_flow) |
| Boolean | linearizeFlowResistanceWat (from Cooling) | false | = true, use linear relation between m_flow and dp for any flow rate |
| Real | deltaMWat (from Cooling) | 0.1 | Fraction of nominal flow rate where flow transitions to laminar |
| Advanced | |||
| Boolean | homotopyInitialization (from Cooling) | true | = true, use homotopy method |
| MediumWat.MassFlowRate | mWat_flow_small (from Cooling) | 1E-4*abs(perCoo.mWat_flow_nominal) | Small mass flow rate for regularization of zero flow |
| MediumAir.MassFlowRate | mAir_flow_small (from Cooling) | 1E-4*abs(perCoo.mAir_flow_nominal) | Small mass flow rate for regularization of zero flow |
| Dynamics › Equations | |||
| Modelica.Fluid.Types.Dynamics | energyDynamics (from Cooling) | Modelica.Fluid.Types.Dynamics.DynamicFreeInitial | Type of energy balance: dynamic (3 initialization options) or steady state |
| Modelica.Fluid.Types.Dynamics | massDynamics (from Cooling) | energyDynamics | Type of mass balance: dynamic (3 initialization options) or steady state |
| Initialization › Cooling | |||
| MediumWat.AbsolutePressure | pWatCoo_start (from Cooling) | MediumWat.p_default | Start value of pressure |
| MediumWat.Temperature | TWatCoo_start (from Cooling) | MediumWat.T_default | Start value of temperature |
| Advanced › Diagnostics | |||
| Boolean | show_T (from Cooling) | false | = true, if actual temperature at port is computed |
| Initialization › Heating | |||
| MediumWat.AbsolutePressure | pWatHea_start | pWatCoo_start | Start value of pressure |
| MediumWat.Temperature | TWatHea_start | TWatCoo_start | Start value of temperature |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Fluid.Interfaces.FluidPort_a | watCoo_a (from Cooling) | Fluid connector watCoo_a (positive design flow direction is from watCoo_a to watCoo_b) | |
| Modelica.Fluid.Interfaces.FluidPort_b | watCoo_b (from Cooling) | Fluid connector watCoo_b (positive design flow direction is from watCoo_a to watCoo_b) | |
| Modelica.Fluid.Interfaces.FluidPort_a | air_a (from Cooling) | Fluid connector air_a (positive design flow direction is from air_a to air_b) | |
| Modelica.Fluid.Interfaces.FluidPort_b | air_b (from Cooling) | Fluid connector air_b (positive design flow direction is from air_a to air_b) | |
| Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a | heaPor (from Cooling) | Heat port, to be connected to room air | |
| Modelica.Fluid.Interfaces.FluidPort_a | watHea_a | Fluid connector a (positive design flow direction is from watHea_a to watHea_b) | |
| Modelica.Fluid.Interfaces.FluidPort_b | watHea_b | Fluid connector b (positive design flow direction is from watHea_a to watHea_b) |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| MediumWat.ThermodynamicState | staWatCoo_a (from Cooling) | MediumWat.setState_phX(watCoo_a.p, noEvent(actualStream(watCoo_a.h_outflow)), noEvent(actualStream(watCoo_a.Xi_outflow))) | Medium properties in port watCoo_a |
| MediumWat.ThermodynamicState | staWatCoo_b (from Cooling) | MediumWat.setState_phX(watCoo_b.p, noEvent(actualStream(watCoo_b.h_outflow)), noEvent(actualStream(watCoo_b.Xi_outflow))) | Medium properties in port watCoo_b |
| MediumAir.ThermodynamicState | staAir_a (from Cooling) | MediumAir.setState_phX(air_a.p, noEvent(actualStream(air_a.h_outflow)), noEvent(actualStream(air_a.Xi_outflow))) | Medium properties in port air_a |
| MediumAir.ThermodynamicState | staAir_b (from Cooling) | MediumAir.setState_phX(air_b.p, noEvent(actualStream(air_b.h_outflow)), noEvent(actualStream(air_b.Xi_outflow))) | Medium properties in port air_b |
| Modelica.Thermal.HeatTransfer.Sources.PrescribedHeatFlow | heaToRoo (from Cooling) | Heat tranferred to the room (in addition to heat from supply air) | |
| Modelica.SIunits.PressureDifference | dpWatCoo (from Cooling) | watCoo_a.p - watCoo_b.p | Pressure difference watCoo_a minus watCoo_b |
| Modelica.SIunits.PressureDifference | dpAir (from Cooling) | air_a.p - air_b.p | Pressure difference air_a minus air_b |
| FixedResistances.PressureDrop | res (from Cooling) | ||
| MediumWat.ThermodynamicState | staHea_a | MediumWat.setState_phX(watHea_a.p, noEvent(actualStream(watHea_a.h_outflow)), noEvent(actualStream(watHea_a.Xi_outflow))) | Medium properties in port watHea_a |
| MediumWat.ThermodynamicState | staHea_b | MediumWat.setState_phX(watHea_b.p, noEvent(actualStream(watHea_b.h_outflow)), noEvent(actualStream(watHea_b.Xi_outflow))) | Medium properties in port watHea_b |
| Modelica.SIunits.PressureDifference | dpWatHea | watHea_a.p - watHea_b.p | Pressure difference between watHea_a and watHea_b |
Revisions
-
June 14, 2016, by Michael Wetter:
Revised implementation. -
May 20, 2016, by Alessandro Maccarini:
First implementation.