partial model DataCenter "Primary only chiller plant system with water-side economizer" replaceable package MediumA = Buildings.Media.Air "Medium model"; replaceable package MediumW = Buildings.Media.Water "Medium model"; parameter Modelica.SIunits.MassFlowRate mAir_flow_nominal=roo.QRoo_flow/(1005 *15) "Nominal mass flow rate at fan"; parameter Modelica.SIunits.Power P_nominal=80E3 "Nominal compressor power (at y=1)"; parameter Modelica.SIunits.TemperatureDifference dTEva_nominal=10 "Temperature difference evaporator inlet-outlet"; parameter Modelica.SIunits.TemperatureDifference dTCon_nominal=10 "Temperature difference condenser outlet-inlet"; parameter Real COPc_nominal=3 "Chiller COP"; parameter Modelica.SIunits.MassFlowRate mCHW_flow_nominal=2*roo.QRoo_flow/( 4200*20) "Nominal mass flow rate at chilled water"; parameter Modelica.SIunits.MassFlowRate mCW_flow_nominal=2*roo.QRoo_flow/( 4200*6) "Nominal mass flow rate at condenser water"; parameter Modelica.SIunits.PressureDifference dp_nominal=500 "Nominal pressure difference"; Buildings.Fluid.Movers.FlowControlled_m_flow fan( redeclare package Medium = MediumA, m_flow_nominal=mAir_flow_nominal, dp(start=249), m_flow(start=mAir_flow_nominal), filteredSpeed=false, energyDynamics=Modelica.Fluid.Types.Dynamics.SteadyState, T_start=293.15) "Fan for air flow through the data center"; Buildings.Fluid.HeatExchangers.DryCoilCounterFlow cooCoi( redeclare package Medium1 = MediumW, redeclare package Medium2 = MediumA, m2_flow_nominal=mAir_flow_nominal, m1_flow_nominal=mCHW_flow_nominal, m1_flow(start=mCHW_flow_nominal), m2_flow(start=mAir_flow_nominal), dp1_nominal(displayUnit="Pa") = 1000, dp2_nominal=249*3, UA_nominal=mAir_flow_nominal*1006*5, energyDynamics=Modelica.Fluid.Types.Dynamics.SteadyStateInitial) "Cooling coil"; Modelica.Blocks.Sources.Constant mFanFlo(k=mAir_flow_nominal) "Mass flow rate of fan"; BaseClasses.SimplifiedRoom roo( redeclare package Medium = MediumA, nPorts=2, rooLen=50, rooWid=30, rooHei=3, m_flow_nominal=mAir_flow_nominal, QRoo_flow=500000) "Room model"; Fluid.Movers.FlowControlled_dp pumCHW( redeclare package Medium = MediumW, m_flow_nominal=mCHW_flow_nominal, m_flow(start=mCHW_flow_nominal), dp(start=325474), filteredSpeed=false, energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial) "Chilled water pump"; Buildings.Fluid.Storage.ExpansionVessel expVesCHW(redeclare package Medium = MediumW, V_start=1) "Expansion vessel"; Buildings.Fluid.HeatExchangers.CoolingTowers.YorkCalc cooTow( redeclare package Medium = MediumW, m_flow_nominal=mCW_flow_nominal, PFan_nominal=6000, TAirInWB_nominal(displayUnit="degC") = 283.15, TApp_nominal=6, dp_nominal=14930 + 14930 + 74650, energyDynamics=Modelica.Fluid.Types.Dynamics.SteadyStateInitial) "Cooling tower"; Buildings.Fluid.Movers.FlowControlled_m_flow pumCW( redeclare package Medium = MediumW, m_flow_nominal=mCW_flow_nominal, dp(start=214992), filteredSpeed=false, energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial) "Condenser water pump"; Buildings.Fluid.HeatExchangers.ConstantEffectiveness wse( redeclare package Medium1 = MediumW, redeclare package Medium2 = MediumW, m1_flow_nominal=mCW_flow_nominal, m2_flow_nominal=mCHW_flow_nominal, eps=0.8, dp2_nominal=0, dp1_nominal=0) "Water side economizer (Heat exchanger)"; Fluid.Actuators.Valves.TwoWayLinear val5( redeclare package Medium = MediumW, m_flow_nominal=mCW_flow_nominal, dpValve_nominal=20902, dpFixed_nominal=89580, y_start=1, filteredOpening=false) "Control valve for condenser water loop of chiller"; Fluid.Actuators.Valves.TwoWayLinear val1( redeclare package Medium = MediumW, m_flow_nominal=mCHW_flow_nominal, dpValve_nominal=20902, filteredOpening=false) "Bypass control valve for economizer. 1: disable economizer, 0: enable economoizer"; Buildings.Fluid.Storage.ExpansionVessel expVesChi(redeclare package Medium = MediumW, V_start=1); Buildings.Examples.ChillerPlant.BaseClasses.Controls.WSEControl wseCon; Modelica.Blocks.Sources.RealExpression expTowTApp(y=cooTow.TApp_nominal) "Cooling tower approach"; Fluid.Chillers.ElectricEIR chi( redeclare package Medium1 = MediumW, redeclare package Medium2 = MediumW, m1_flow_nominal=mCW_flow_nominal, m2_flow_nominal=mCHW_flow_nominal, dp2_nominal=0, dp1_nominal=0, per=Buildings.Fluid.Chillers.Data.ElectricEIR.ElectricEIRChiller_Carrier_19XR_742kW_5_42COP_VSD(), energyDynamics=Modelica.Fluid.Types.Dynamics.SteadyStateInitial); Fluid.Actuators.Valves.TwoWayLinear val6( redeclare package Medium = MediumW, m_flow_nominal=mCHW_flow_nominal, dpValve_nominal=20902, dpFixed_nominal=14930 + 89580, y_start=1, filteredOpening=false) "Control valve for chilled water leaving from chiller"; Buildings.Examples.ChillerPlant.BaseClasses.Controls.ChillerSwitch chiSwi( deaBan(displayUnit="K") = 2.2) "Control unit switching chiller on or off "; Buildings.Examples.ChillerPlant.BaseClasses.Controls.LinearPiecewiseTwo linPieTwo( x0=0, x2=1, x1=0.5, y11=1, y21=273.15 + 5.56, y10=0.2, y20=273.15 + 22) "Translate the control signal for chiller setpoint reset"; Modelica.Blocks.Sources.Constant TAirSet(k=273.15 + 27) "Set temperature for air supply to the room"; Modelica.Blocks.Math.BooleanToReal chiCon "Contorl signal for chiller"; Fluid.Actuators.Valves.TwoWayLinear val4( redeclare package Medium = MediumW, m_flow_nominal=mCW_flow_nominal, dpValve_nominal=20902, dpFixed_nominal=59720, y_start=0, filteredOpening=false) "Control valve for condenser water loop of economizer"; Buildings.Fluid.Sensors.TemperatureTwoPort TAirSup(redeclare package Medium = MediumA, m_flow_nominal=mAir_flow_nominal) "Supply air temperature to data center"; Buildings.Fluid.Sensors.TemperatureTwoPort TCHWEntChi(redeclare package Medium = MediumW, m_flow_nominal=mCHW_flow_nominal) "Temperature of chilled water entering chiller"; Buildings.Fluid.Sensors.TemperatureTwoPort TCWLeaTow(redeclare package Medium = MediumW, m_flow_nominal=mCW_flow_nominal) "Temperature of condenser water leaving the cooling tower"; Modelica.Blocks.Sources.Constant cooTowFanCon(k=1) "Control singal for cooling tower fan"; Fluid.Actuators.Valves.TwoWayEqualPercentage valByp( redeclare package Medium = MediumW, m_flow_nominal=mCHW_flow_nominal, dpValve_nominal=20902, dpFixed_nominal=14930, y_start=0, filteredOpening=false) "Bypass valve for chiller."; Buildings.Examples.ChillerPlant.BaseClasses.Controls.KMinusU KMinusU(k=1); Fluid.Actuators.Valves.TwoWayLinear val3( redeclare package Medium = MediumW, m_flow_nominal=mCHW_flow_nominal, dpValve_nominal=20902, dpFixed_nominal=59720 + 1000, filteredOpening=false) "Control valve for economizer. 0: disable economizer, 1: enable economoizer"; Buildings.Fluid.Sensors.TemperatureTwoPort TCHWLeaCoi(redeclare package Medium = MediumW, m_flow_nominal=mCHW_flow_nominal) "Temperature of chilled water leaving the cooling coil"; Buildings.BoundaryConditions.WeatherData.ReaderTMY3 weaData(filNam= "modelica://Buildings/Resources/weatherdata/USA_CA_San.Francisco.Intl.AP.724940_TMY3.mos"); BoundaryConditions.WeatherData.Bus weaBus; Fluid.FixedResistances.FixedResistanceDpM res( redeclare package Medium = MediumW, m_flow_nominal=mCHW_flow_nominal, dp_nominal=89580); Modelica.Blocks.Math.Gain gain(k=20*6485); Modelica.Blocks.Math.Feedback feedback; Modelica.Blocks.Logical.GreaterThreshold greaterThreshold; Modelica.Blocks.Logical.Or or1; Modelica.Blocks.Math.BooleanToReal mCWFlo(realTrue=mCW_flow_nominal) "Mass flow rate of condensor loop"; Modelica.Blocks.Sources.RealExpression PHVAC(y=fan.P + pumCHW.P + pumCW.P + cooTow.PFan + chi.P) "Power consumed by HVAC system"; Modelica.Blocks.Sources.RealExpression PIT(y=roo.QSou.Q_flow) "Power consumed by IT"; Modelica.Blocks.Continuous.Integrator EHVAC(initType=Modelica.Blocks.Types.Init.InitialState, y_start=0) "Energy consumed by HVAC"; Modelica.Blocks.Continuous.Integrator EIT(initType=Modelica.Blocks.Types.Init.InitialState, y_start=0) "Energy consumed by IT"; equation connect(expVesCHW.port_a, cooCoi.port_b1); connect(expTowTApp.y, wseCon.towTApp); connect(chiSwi.y, chiCon.u); connect(cooTow.port_b, pumCW.port_a); connect(val5.port_a, chi.port_b1); connect(expVesChi.port_a, chi.port_b1); connect(val4.port_a, wse.port_b1); connect(chiSwi.y, chi.on); connect(linPieTwo.y[2], chi.TSet); connect(chiCon.y, val5.y); connect(linPieTwo.y[2], chiSwi.TSet); connect(cooTowFanCon.y, cooTow.y); connect(cooCoi.port_b2, fan.port_a); connect(mFanFlo.y, fan.m_flow_in); connect(wse.port_a2, val3.port_b); connect(wseCon.y2, val1.y); connect(wseCon.y1, val3.y); connect(wseCon.y1, val4.y); connect(TAirSup.port_a, fan.port_b); connect(roo.airPorts[1],TAirSup. port_b); connect(roo.airPorts[2], cooCoi.port_a2); connect(TCHWLeaCoi.port_a, pumCHW.port_b); connect(TCHWEntChi.port_b, valByp.port_a); connect(TCHWEntChi.port_a, val1.port_b); connect(val1.port_a, TCHWLeaCoi.port_b); connect(val3.port_a, TCHWLeaCoi.port_b); connect(TCWLeaTow.port_b, chi.port_a1); connect(TCWLeaTow.port_b, wse.port_a1); connect(TCHWEntChi.T, chiSwi.chiCHWST); connect(wseCon.wseCWST, TCWLeaTow.T); connect(wseCon.wseCHWST, TCHWLeaCoi.T); connect(weaData.weaBus, weaBus); connect(wseCon.TWetBul, weaBus.TWetBul); connect(cooTow.TAir, weaBus.TWetBul); connect(TCHWEntChi.port_a, wse.port_b2); connect(valByp.port_b, val6.port_b); connect(TCHWEntChi.port_b, chi.port_a2); connect(val5.port_b, cooTow.port_a); connect(val4.port_b, cooTow.port_a); connect(pumCW.port_b, TCWLeaTow.port_a); connect(cooCoi.port_a1, res.port_a); connect(chiCon.y, KMinusU.u); connect(KMinusU.y, valByp.y); connect(chiCon.y, val6.y); connect(linPieTwo.y[1], gain.u); connect(gain.y, pumCHW.dp_in); connect(TAirSet.y, feedback.u2); connect(TAirSup.T, feedback.u1); connect(chi.port_b2, val6.port_a); connect(res.port_b, val6.port_b); connect(pumCHW.port_a, cooCoi.port_b1); connect(greaterThreshold.u, wseCon.y1); connect(or1.u1, greaterThreshold.y); connect(or1.u2, chiSwi.y); connect(or1.y, mCWFlo.u); connect(mCWFlo.y, pumCW.m_flow_in); connect(PHVAC.y, EHVAC.u); connect(PIT.y, EIT.u); end DataCenter;

model DataCenterContinuousTimeControl extends Buildings.Examples.ChillerPlant.DataCenterContinuousTimeControl; Modelica.Blocks.Interfaces.RealOutput PAC "Alternate current power required for IT"; Modelica.Blocks.Interfaces.RealOutput PDC "Direct current power required for IT"; equation connect(PHVAC.y, PAC); connect(PIT.y, PDC); end DataCenterContinuousTimeControl;

model SimplifiedRoom "Simplified data center room" extends Buildings.BaseClasses.BaseIconLow; replaceable package Medium = Modelica.Media.Interfaces.PartialMedium "Medium model"; parameter Integer nPorts=0 "Number of parts"; parameter Modelica.SIunits.Length rooLen "Length of the room"; parameter Modelica.SIunits.Length rooWid "Width of the room"; parameter Modelica.SIunits.Height rooHei "Height of the room"; parameter Modelica.SIunits.Power QRoo_flow "Heat generation of the computer room"; Buildings.Fluid.MixingVolumes.MixingVolume rooVol( redeclare each package Medium = Medium, nPorts=nPorts, V=rooLen*rooWid*rooHei, m_flow_nominal=m_flow_nominal, energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial, final T_start=293.15, final prescribedHeatFlowRate=true) "Volume of air in the room"; Modelica.Fluid.Vessels.BaseClasses.VesselFluidPorts_b airPorts[nPorts]( redeclare each package Medium = Medium) "Fluid inlets and outlets"; Modelica.Thermal.HeatTransfer.Sources.PrescribedHeatFlow QSou "Heat source of the room"; Modelica.Blocks.Sources.Ramp ramp( height=QRoo_flow, offset=0, duration=36000, startTime=0); parameter Modelica.SIunits.MassFlowRate m_flow_nominal "Nominal mass flow rate"; equation connect(rooVol.ports, airPorts); connect(QSou.port, rooVol.heatPort); connect(ramp.y, QSou.Q_flow); end SimplifiedRoom;