modelChiller
Base subsystem with heat recovery chiller
Extends from Buildings.Obsolete.BaseClasses.ObsoleteModel.
Information
This is a model for a chiller system with constant speed evaporator and condenser pumps, and mixing valves modulated to maintain a minimum condenser inlet temperature (resp. maximum evaporator inlet temperature).
The system is controlled based on the logic described in Buildings.Obsolete.DHC.ETS.Combined.Controls.Chiller. The pump flow rate is considered proportional to the pump speed under the assumption of a constant flow resistance for both the condenser and the evaporator loops. This assumption is justified by the connection of the loops to the buffer tanks, and the additional assumption that the bypass branch of the mixing valves is balanced with the direct branch.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Buildings.Fluid.Chillers.Data.ElectricEIR.Generic | dat | Chiller performance data | |
| Assumptions | |||
| Boolean | allowFlowReversal | false | = true to allow flow reversal, false restricts to design direction (port_a -> port_b) |
| Nominal condition | |||
| Modelica.Units.SI.PressureDifference | dpCon_nominal | Nominal pressure drop accross condenser | |
| Modelica.Units.SI.PressureDifference | dpEva_nominal | Nominal pressure drop accross evaporator | |
| Modelica.Units.SI.Pressure | dpValCon_nominal | dpCon_nominal/2 | Nominal pressure drop accross control valve on condenser side |
| Modelica.Units.SI.Pressure | dpValEva_nominal | dpEva_nominal/2 | Nominal pressure drop accross control valve on evaporator side |
| Controls | |||
| Modelica.Units.SI.Temperature | TConWatEntMin | dat.TConEntMin | Minimum value of condenser water entering temperature |
| Modelica.Units.SI.Temperature | TEvaWatEntMax | dat.TEvaLvgMax - dat.QEva_flow_nominal/cp_default/dat.mEva_flow_nominal | Maximum value of evaporator water entering temperature |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Buildings.Controls.OBC.CDL.Interfaces.BooleanInput | uHea | Heating enable signal | |
| Buildings.Controls.OBC.CDL.Interfaces.BooleanInput | uCoo | Cooling enable signal | |
| Buildings.Controls.OBC.CDL.Interfaces.RealInput | TChiWatSupSet | Chilled water supply temperature set point (may be reset down) | |
| Modelica.Fluid.Interfaces.FluidPort_a | port_aChiWat | Fluid port for chilled water return | |
| Modelica.Fluid.Interfaces.FluidPort_b | port_bChiWat | Fluid port for chilled water supply | |
| Modelica.Fluid.Interfaces.FluidPort_a | port_aHeaWat | Fluid port for heating water return | |
| Modelica.Fluid.Interfaces.FluidPort_b | port_bHeaWat | Fluid port for heating water supply | |
| Buildings.Controls.OBC.CDL.Interfaces.RealOutput | PChi | Chiller power | |
| Buildings.Controls.OBC.CDL.Interfaces.RealOutput | PPum | Pump power | |
| Buildings.Fluid.Chillers.ElectricEIR | chi | Water cooled chiller (ports indexed 1 are on condenser side) | |
| Buildings.DHC.ETS.BaseClasses.Pump_m_flow | pumCon | Condenser pump | |
| Buildings.DHC.ETS.BaseClasses.Pump_m_flow | pumEva | Evaporator pump | |
| Buildings.Obsolete.DHC.ETS.Combined.Controls.Chiller | con | Controller | |
| Buildings.Fluid.Sensors.TemperatureTwoPort | senTConLvg | Condenser water leaving temperature | |
| Buildings.Fluid.Sensors.TemperatureTwoPort | senTConEnt | Condenser water entering temperature | |
| Buildings.Fluid.Sensors.TemperatureTwoPort | senTEvaEnt | Evaporator water entering temperature | |
| Buildings.Fluid.Sensors.TemperatureTwoPort | senTEvaLvg | Evaporator water leaving temperature | |
| Buildings.DHC.ETS.BaseClasses.Junction | splEva | Flow splitter for the evaporator water circuit | |
| Buildings.DHC.ETS.BaseClasses.Junction | splConMix | Flow splitter | |
| Buildings.Fluid.Actuators.Valves.ThreeWayEqualPercentageLinear | valEva | Control valve for maximum evaporator water entering temperature | |
| Buildings.Fluid.Actuators.Valves.ThreeWayEqualPercentageLinear | valCon | Control valve for minimum condenser water entering temperature | |
| Buildings.Controls.OBC.CDL.Conversions.BooleanToReal | booToRea | Constant speed primary pumps control signal | |
| Buildings.Controls.OBC.CDL.Reals.Add | add2 | ||
| Buildings.Controls.OBC.CDL.Reals.MultiplyByParameter | gai1 | Scale to nominal mass flow rate | |
| Buildings.Controls.OBC.CDL.Reals.MultiplyByParameter | gai2 | Scale to nominal mass flow rate |
Contents
| Name | Description |
|---|---|
| Medium | Medium model |
Revisions
-
November 3, 2025, by Michael Wetter:
Moved toBuildings.Obsolete.
This is for #4354. -
March 27, 2024, by David Blum:
Update icon and fix port orientation to align with convention.
This is for issue #3606. -
July 31, 2020, by Antoine Gautier:
First implementation.