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Buildings.Fluid.DataCenters.Racks.RearDoorHeatExchangers.Data.Passive

Data records for passive rear door heat exchangers

Information

This package contains data records for passive rear door heat exchangers. In a passive rear door heat exchanger, the server fans inside the rack drive airflow through the heat exchanger.

Extends from Modelica.Icons.MaterialPropertiesPackage (Icon for package containing property classes).

Package Content

Name Description
Buildings.Fluid.DataCenters.Racks.RearDoorHeatExchangers.Data.Passive.Generic Generic Data record for passive rear door heat exchanger

Buildings.Fluid.DataCenters.Racks.RearDoorHeatExchangers.Data.Passive.Generic Buildings.Fluid.DataCenters.Racks.RearDoorHeatExchangers.Data.Passive.Generic

Data record for passive rear door heat exchanger

Information

Generic data record for a rear door heat exchanger used in hybrid IT racks.

The rear door heat exchanger is placed at the air outlet of the rack. It removes heat from the warm exhaust air using a liquid coolant. The heat exchanger effectiveness eps_nominal is computed from the design heat duty, the inlet temperatures, and the minimum capacity flow rate.

The parameter cpCoo_nominal is the specific heat capacity of the coolant at nominal conditions, which defaults to the value for water.

Extends from Modelica.Icons.Record (Icon for records).

Contents

TypeNameDefaultDescription
SpecificHeatCapacitycpCoo_nominalBuildings.Media.Water.cp_constSpecific heat capacity of rear door heat exchanger coolant fluid [J/(kg.K)]
SpecificHeatCapacitycpAir_nominalBuildings.Utilities.Psychrom...Specific heat capacity of air [J/(kg.K)]
Nominal condition
MassFlowRatemAir_flow_nominal Design air mass flow rate for heat exchanger [kg/s]
MassFlowRatemCoo_flow_nominal Design coolant flow rate for heat exchanger parameterization [kg/s]
HeatFlowRateQ_flow_nominal Cooling capacity at design condition (negative number) [W]
TemperatureTAirIn_nominal Air inlet nominal temperature (air entering rear door heat exchanger) [K]
TemperatureTCooIn_nominal Rear door coolant inlet nominal temperature [K]
PressureDifferencedpCoo_nominal10000Coolant-side pressure drop at nominal flow rate [Pa]
PressureDifferencedpAir_nominal200Air-side pressure drop at nominal flow rate [Pa]

Modelica definition

record Generic "Data record for passive rear door heat exchanger" extends Modelica.Icons.Record; parameter Modelica.Units.SI.MassFlowRate mAir_flow_nominal "Design air mass flow rate for heat exchanger"; parameter Modelica.Units.SI.MassFlowRate mCoo_flow_nominal "Design coolant flow rate for heat exchanger parameterization"; parameter Modelica.Units.SI.SpecificHeatCapacity cpCoo_nominal= Buildings.Media.Water.cp_const "Specific heat capacity of rear door heat exchanger coolant fluid"; parameter Modelica.Units.SI.SpecificHeatCapacity cpAir_nominal = Buildings.Utilities.Psychrometrics.Constants.cpAir "Specific heat capacity of air"; parameter Modelica.Units.SI.HeatFlowRate Q_flow_nominal(max=0) "Cooling capacity at design condition (negative number)"; parameter Modelica.Units.SI.Temperature TAirIn_nominal(displayUnit="degC") "Air inlet nominal temperature (air entering rear door heat exchanger)"; parameter Modelica.Units.SI.Temperature TCooIn_nominal(displayUnit="degC") "Rear door coolant inlet nominal temperature"; parameter Modelica.Units.SI.PressureDifference dpCoo_nominal( min=0, displayUnit="Pa") = 10000 "Coolant-side pressure drop at nominal flow rate"; parameter Modelica.Units.SI.PressureDifference dpAir_nominal( min=0, displayUnit="Pa") = 200 "Air-side pressure drop at nominal flow rate"; // final parameter Modelica.Units.SI.TemperatureDifference dTAir_nominal(min=1) = // -Q_flow_nominal/(mAir_flow_nominal*cpAir_nominal) // "Air temperature difference across rear door heat exchanger"; // final parameter Modelica.Units.SI.TemperatureDifference dTCoo_nominal= // Q_flow_nominal/(mCoo_flow_nominal*cpCoo_nominal) // "Rear door coolant temperature difference"; end Generic;