recordGeneric_2MW
Generic data record for a 2 MW CDU
Extends from Buildings.Fluid.DataCenterEquipment.CDUs.LiquidToLiquid.Data.Generic_epsNTU (Generic data record for a CDU that uses the epsilon-NTU method to compute the thermal performance).
Information
Generic record for a 2 MW CDU.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.Temperature | TPlaIn_nominal (from Generic_epsNTU) | TRacOut_nominal - TApp_nominal | Inlet temperature from cooling plant loop |
| Modelica.Units.SI.Temperature | TPlaOut_nominal (from Generic_epsNTU) | TPlaIn_nominal - Q_flow_nominal/CPla_flow_nominal | Outlet temperature to cooling plant loop |
| Modelica.Units.SI.Temperature | TRacIn_nominal (from Generic_epsNTU) | TRacOut_nominal - Q_flow_nominal/CRac_flow_nominal | Inlet temperature from IT rack loop |
| Modelica.Units.SI.DynamicViscosity | etaPla_default (from Generic_epsNTU) | Buildings.Fluid.DataCenterEquipment.CDUs.LiquidToLiquid.Data.BaseClasses.dynamicViscosity_TX_a(medium = medPla, X_a = XGlyPla, T = TRacOut_nominal) | Dynamic viscosity for plant-side performance data |
| Modelica.Units.SI.SpecificHeatCapacity | cpPla_default (from Generic_epsNTU) | Buildings.Fluid.DataCenterEquipment.CDUs.LiquidToLiquid.Data.BaseClasses.specificHeatCapacityCp_TX_a(medium = medPla, X_a = XGlyPla, T = TRacOut_nominal) | Specific heat capacity at constant pressure for plant-side performance data |
| Modelica.Units.SI.ThermalConductivity | kPla_default (from Generic_epsNTU) | Buildings.Fluid.DataCenterEquipment.CDUs.LiquidToLiquid.Data.BaseClasses.thermalConductivity_TX_a(medium = medPla, X_a = XGlyPla, T = TRacOut_nominal) | Thermal conductivity for plant-side performance data |
| Modelica.Units.SI.PrandtlNumber | PrPla_default (from Generic_epsNTU) | Buildings.Fluid.DataCenterEquipment.CDUs.LiquidToLiquid.Data.BaseClasses.prandtlNumber_TX_a(medium = medPla, X_a = XGlyPla, T = TRacOut_nominal) | Prandtl number for plant-side performance data |
| Modelica.Units.SI.DynamicViscosity | etaRac_default (from Generic_epsNTU) | Buildings.Fluid.DataCenterEquipment.CDUs.LiquidToLiquid.Data.BaseClasses.dynamicViscosity_TX_a(medium = medRac, X_a = XGlyRac, T = TRacOut_nominal) | Dynamic viscosity for rack-side performance data |
| Modelica.Units.SI.SpecificHeatCapacity | cpRac_default (from Generic_epsNTU) | Buildings.Fluid.DataCenterEquipment.CDUs.LiquidToLiquid.Data.BaseClasses.specificHeatCapacityCp_TX_a(medium = medRac, X_a = XGlyRac, T = TRacOut_nominal) | Specific heat capacity at constant pressure for rack-side performance data |
| Modelica.Units.SI.ThermalConductivity | kRac_default (from Generic_epsNTU) | Buildings.Fluid.DataCenterEquipment.CDUs.LiquidToLiquid.Data.BaseClasses.thermalConductivity_TX_a(medium = medRac, X_a = XGlyRac, T = TRacOut_nominal) | Thermal conductivity for rack-side performance data |
| Modelica.Units.SI.PrandtlNumber | PrRac_default (from Generic_epsNTU) | Buildings.Fluid.DataCenterEquipment.CDUs.LiquidToLiquid.Data.BaseClasses.prandtlNumber_TX_a(medium = medRac, X_a = XGlyRac, T = TRacOut_nominal) | Prandtl number for rack-side performance data |
| Modelica.Units.SI.Density | rhoRac_default (from Generic_epsNTU) | Buildings.Fluid.DataCenterEquipment.CDUs.LiquidToLiquid.Data.BaseClasses.density_TX_a(medium = medRac, X_a = XGlyRac, T = TRacOut_nominal) | Mass density for rack-side performance data |
| Buildings.Fluid.Movers.BaseClasses.Characteristics.efficiencyParameters | pumpEfficiency (from Generic_epsNTU) | Total pump efficiency vs. volumetric flow rate | |
| Modelica.Units.SI.ThermalConductance | CPla_flow_nominal (from Generic_epsNTU) | mPla_flow_nominal*cpPla_default | Capacity flow rate at nominal conditions on cooling plant side |
| Modelica.Units.SI.ThermalConductance | CRac_flow_nominal (from Generic_epsNTU) | mRac_flow_nominal*cpRac_default | Capacity flow rate at nominal conditions on rack side |
| Modelica.Units.SI.TemperatureDifference | dTPla_nominal (from Generic_epsNTU) | -Q_flow_nominal/CPla_flow_nominal | Fluid temperature difference at nominal conditions on cooling plant side |
| Modelica.Units.SI.TemperatureDifference | dTRac_nominal (from Generic_epsNTU) | Q_flow_nominal/CRac_flow_nominal | Fluid temperature difference at nominal conditions on rack side |
| Nominal thermal performance | |||
| Modelica.Units.SI.HeatFlowRate | Q_flow_nominal (from Generic_epsNTU) | Nominal heat flow rate (negative as it is for cooling) | |
| Modelica.Units.SI.TemperatureDifference | TApp_nominal (from Generic_epsNTU) | Approach temperature on IT loop size (to cooling minus from rack) | |
| Modelica.Units.SI.Temperature | TRacOut_nominal (from Generic_epsNTU) | Outlet temperature to IT rack loop | |
| Nominal condition | |||
| Modelica.Units.SI.MassFlowRate | mPla_flow_nominal (from Generic_epsNTU) | Nominal mass flow rate on cooling plant side | |
| Modelica.Units.SI.MassFlowRate | mRac_flow_nominal (from Generic_epsNTU) | Nominal mass flow rate on rack side | |
| Modelica.Units.SI.PressureDifference | dpHexPla_nominal (from Generic_epsNTU) | Heat exchanger design pressure drop at plant side | |
| Modelica.Units.SI.PressureDifference | dpHexRac_nominal (from Generic_epsNTU) | dpHexPla_nominal | Heat exchanger design pressure drop at rack side |
| Modelica.Units.SI.PressureDifference | dpFilRac_nominal (from Generic_epsNTU) | 65000 | Clean filter design pressure drop at rack-side |
| Flow resistance › Medium 1 | |||
| Real | deltaMPla (from Generic_epsNTU) | 0.1 | Fraction of nominal flow rate where flow transitions to laminar on cooling plant side |
| Real | nPla (from Generic_epsNTU) | 2 | Flow exponent, n=1 for laminar, n=2 for turbulent |
| Flow resistance › Medium 2 | |||
| Real | nRac (from Generic_epsNTU) | 2 | Flow exponent, n=1 for laminar, n=2 for turbulent |
| Real | nFilRac (from Generic_epsNTU) | 1.76 | Flow exponent for filter on rack-side, n=1 for laminar, n=2 for turbulent |
| Real | deltaMRac (from Generic_epsNTU) | 0.1 | Fraction of nominal flow rate where flow transitions to laminar on rack side |
| Plant-side medium for performance data | |||
| Fluid.DataCenterEquipment.CDUs.Types.Media | medPla (from Generic_epsNTU) | Buildings.Fluid.DataCenterEquipment.CDUs.Types.Media.Water | Media for which performance data are specified |
| Real | phiGlyPla (from Generic_epsNTU) | 0 | Glycol volume fraction for which performance data are specified |
| Modelica.Units.SI.MassFraction | XGlyPla (from Generic_epsNTU) | if medPla == Buildings.Fluid.DataCenterEquipment.CDUs.Types.Media.Water then 0 elseif medPla == Buildings.Fluid.DataCenterEquipment.CDUs.Types.Media.EthyleneGlycol then Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.volumeToMassFraction(phi = phiGlyPla, T = TRacOut_nominal) else Buildings.Media.Antifreeze.Functions.PropyleneGlycolWater.volumeToMassFraction(phi = phiGlyPla, T = TRacOut_nominal) | Glycol mass fraction for which performance data are specified. Set to 0 if only water is used. |
| Rack-side medium for performance data | |||
| Fluid.DataCenterEquipment.CDUs.Types.Media | medRac (from Generic_epsNTU) | Media for which performance data are specified | |
| Real | phiGlyRac (from Generic_epsNTU) | Glycol volume fraction for which performance data are specified. Set to 0 if only water is used. | |
| Modelica.Units.SI.MassFraction | XGlyRac (from Generic_epsNTU) | if medRac == Buildings.Fluid.DataCenterEquipment.CDUs.Types.Media.Water then 0 elseif medRac == Buildings.Fluid.DataCenterEquipment.CDUs.Types.Media.EthyleneGlycol then Buildings.Media.Antifreeze.Functions.EthyleneGlycolWater.volumeToMassFraction(phi = phiGlyRac, T = TRacOut_nominal) else Buildings.Media.Antifreeze.Functions.PropyleneGlycolWater.volumeToMassFraction(phi = phiGlyRac, T = TRacOut_nominal) | Glycol mass fraction for which performance data are specified |
| Valve | |||
| Modelica.Units.SI.PressureDifference | dpValve_nominal (from Generic_epsNTU) | dpHexPla_nominal | Nominal pressure drop of fully open valve on chiller plant side |
| Dynamics › Valve | |||
| Modelica.Units.SI.Time | strokeTime (from Generic_epsNTU) | 120 | Time needed to fully open or close actuator |
| Dynamics › Pump | |||
| Modelica.Units.SI.Time | riseTime (from Generic_epsNTU) | 30 | Time needed to change motor speed between zero and full speed |
| Pump | |||
| Modelica.Units.SI.PressureDifference | dpPumpExt_nominal (from Generic_epsNTU) | Pump head available for flow network that is connected to the CDU on the rack-side at m_flow_nominal | |
| Buildings.Fluid.Movers.BaseClasses.Characteristics.flowParameters | pumpExtHead (from Generic_epsNTU) | Pump head available for flow network that is connected to the CDU on the rack-side | |
| Buildings.Fluid.Movers.BaseClasses.Characteristics.flowParameters | pumpHead (from Generic_epsNTU) | Actual head of the pump, composed of external pump head, and head used for heat exchanger and filter | |
| Advanced › Heat transfer coefficients | |||
| Real | r_nominal (from Generic_epsNTU) | (kPla_default*(mPla_flow_nominal/etaPla_default)^nConPla*PrPla_default^(1/3))/(kRac_default*(mRac_flow_nominal/etaRac_default)^nConRac*PrRac_default^(1/3)) | Ratio between convective heat transfer coefficients at nominal conditions, r_nominal = hAPla_nominal/hARac_nominal |
| Real | nConPla (from Generic_epsNTU) | 0.8 | Exponent for convective heat transfer coefficient, h~m_flow^nCon |
| Real | nConRac (from Generic_epsNTU) | nConPla | Exponent for convective heat transfer coefficient, h~m_flow^nCon |
| Advanced › Expansion vessel | |||
| Modelica.Units.SI.Volume | VExp (from Generic_epsNTU) | -0.056/2E6*Q_flow_nominal | Size of expansion vessel on IT loop side |
Revisions
-
April 13, 2026, by Michael Wetter:
First implementation.