modelEvaporatorVariableSpeed
Evaporator coil with variable speed compressor
Extends from Buildings.Templates.Components.Interfaces.PartialCoil (Interface class for coil).
Information
This is a model for a direct expansion cooling coil with a
variable speed compressor.
The compressor speed is modulated with the fractional speed
signal y (real between 0 and 1).
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Buildings.Templates.Components.Data.Coil | dat (from PartialCoil) | Design and operating parameters | |
| Modelica.Units.SI.MassFlowRate | mAir_flow_nominal (from PartialCoil) | dat.mAir_flow_nominal | Air mass flow rate |
| Modelica.Units.SI.PressureDifference | dpAir_nominal (from PartialCoil) | dat.dpAir_nominal | Air pressure drop |
| Modelica.Units.SI.HeatFlowRate | Q_flow_nominal (from PartialCoil) | dat.Q_flow_nominal | Nominal heat flow rate |
| Boolean | have_dryCon | true | Set to true for air-cooled condenser, false for evaporative condenser |
| Assumptions | |||
| Boolean | allowFlowReversal (from PartialTwoPort) | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
| Boolean | allowFlowReversalAir (from PartialCoil) | true | = true to allow flow reversal, false restricts to design direction - Air side |
| Boolean | allowFlowReversalLiq (from PartialCoil) | true | = true to allow flow reversal, false restricts to design direction - CHW and HW side |
| Nominal condition | |||
| Modelica.Units.SI.MassFlowRate | m_flow_nominal (from PartialTwoPortInterface) | Nominal mass flow rate | |
| Advanced | |||
| Modelica.Units.SI.MassFlowRate | m_flow_small (from PartialTwoPortInterface) | 1E-4*abs(m_flow_nominal) | Small mass flow rate for regularization of zero flow |
| Advanced › Diagnostics | |||
| Boolean | show_T (from PartialTwoPortInterface) | false | = true, if actual temperature at port is computed |
| Configuration | |||
| Buildings.Templates.Components.Types.Coil | typ (from PartialCoil) | Equipment type | |
| Buildings.Templates.Components.Types.Valve | typVal (from PartialCoil) | Type of valve | |
| Boolean | have_sou (from PartialCoil) | typ == Buildings.Templates.Components.Types.Coil.WaterBasedHeating or typ == Buildings.Templates.Components.Types.Coil.WaterBasedCooling | Set to true for fluid ports on the source side |
| Boolean | have_weaBus (from PartialCoil) | typ == Buildings.Templates.Components.Types.Coil.EvaporatorMultiStage or typ == Buildings.Templates.Components.Types.Coil.EvaporatorVariableSpeed | Set to true to use a weather bus |
| Dynamics › Nominal condition | |||
| Modelica.Units.SI.Time | tau (from PartialCoil) | 20 | Time constant at nominal flow |
| Dynamics › Conservation equations | |||
| Modelica.Fluid.Types.Dynamics | energyDynamics (from PartialCoil) | Modelica.Fluid.Types.Dynamics.DynamicFreeInitial | Type of energy balance: dynamic (3 initialization options) or steady state |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Fluid.Interfaces.FluidPort_a | port_a (from PartialTwoPort) | Fluid connector a (positive design flow direction is from port_a to port_b) | |
| Modelica.Fluid.Interfaces.FluidPort_b | port_b (from PartialTwoPort) | Fluid connector b (positive design flow direction is from port_a to port_b) | |
| Modelica.Fluid.Interfaces.FluidPort_a | port_aSou (from PartialCoil) | Fluid connector a (positive design flow direction is from port_a to port_b) | |
| Modelica.Fluid.Interfaces.FluidPort_b | port_bSou (from PartialCoil) | Fluid connector b (positive design flow direction is from port_a to port_b) | |
| Buildings.BoundaryConditions.WeatherData.Bus | busWea (from PartialCoil) | Weather bus | |
| Buildings.Templates.Components.Interfaces.Bus | bus (from PartialCoil) | Control bus |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.MassFlowRate | m_flow (from PartialTwoPortInterface) | port_a.m_flow | Mass flow rate from port_a to port_b (m_flow > 0 is design flow direction) |
| Modelica.Units.SI.PressureDifference | dp (from PartialTwoPortInterface) | port_a.p - port_b.p | Pressure difference between port_a and port_b |
| Medium.ThermodynamicState | sta_a (from PartialTwoPortInterface) | if allowFlowReversal then Medium.setState_phX(port_a.p, noEvent(actualStream(port_a.h_outflow)), noEvent(actualStream(port_a.Xi_outflow))) else Medium.setState_phX(port_a.p, noEvent(inStream(port_a.h_outflow)), noEvent(inStream(port_a.Xi_outflow))) | Medium properties in port_a |
| Medium.ThermodynamicState | sta_b (from PartialTwoPortInterface) | if allowFlowReversal then Medium.setState_phX(port_b.p, noEvent(actualStream(port_b.h_outflow)), noEvent(actualStream(port_b.Xi_outflow))) else Medium.setState_phX(port_b.p, noEvent(port_b.h_outflow), noEvent(port_b.Xi_outflow)) | Medium properties in port_b |
| Buildings.Fluid.DXSystems.Cooling.AirSource.VariableSpeed | hex | Heat exchanger | |
| Modelica.Blocks.Routing.RealPassThrough | TWetBul | ||
| Modelica.Blocks.Routing.RealPassThrough | TDry |