modelLiquidCooledSinglePhase
Hybrid rack model combining liquid-cooled and air-cooled components
Information
Model of a hybrid IT rack that combines liquid-cooled and air-cooled components.
This model integrates two separate cooling technologies in a single rack.
The liquid cooling component uses cold plates and is based on
Buildings.Fluid.DataCenterEquipment.Racks.LiquidCooledSinglePhase.ColdPlateR_P,
while the air cooling component with integrated fans is based on
Buildings.Fluid.DataCenterEquipment.Racks.AirCooled.Rack_u.
The model has separate fluid ports for each cooling loop.
For liquid cooling, portLiq_a and portLiq_b serve as the inlet and outlet ports.
For air cooling, portAir_a and portAir_b serve as the inlet and outlet ports.
Each cooling system has its own input for the electrical power consumption by the IT equipment.
The input PLiq specifies the power consumption for the liquid-cooled IT equipment,
and the input PAir specifies the power consumption for the air-cooled IT equipment.
Note that PAir does not include the power to operate the fan, as this is an output of the model.
The model provides three power consumption outputs on the right side.
The output PLiqTot is the electric power consumed by liquid-cooled IT.
The output PAirTot is the total electric power consumed by air-cooled IT, including fan energy.
The output PAirFan is the electric power consumed by the fan for air-cooled IT.
Parameters
| Type | Name | Default | Description |
|---|
| Buildings.Fluid.DataCenterEquipment.Racks.Hybrid.Data.LiquidCooledSinglePhase.Generic | dat | | Performance data |
| Dynamics › Liquid cooling |
| Modelica.Fluid.Types.Dynamics | energyDynamicsLiq | Modelica.Fluid.Types.Dynamics.DynamicFreeInitial | Type of energy balance for liquid-cooled component: dynamic (3 initialization options) or steady state |
| Modelica.Units.SI.Time | tauLiq | 2 | Time constant of liquid outlet temperature at nominal flow |
| Initialization › Liquid cooling |
| Modelica.Units.SI.Temperature | TLiq_start | 293.15 | Start value of liquid temperature |
| Liquid cooling |
| Modelica.Units.SI.VolumeFlowRate | VColPla_flow_nominal | sum(dat.liq.theRes.V_flow)/size(dat.liq.theRes.V_flow, 1) | Design flow rate of one cold plate for liquid cooling |
| Real | nColPla | dat.liq.PIT_nominal/(VColPla_flow_nominal*1000*4200*(dat.liq.PIT_nominal/(dat.liq.m_flow_nominal*4200))) | Number of cold plates for liquid cooling |
| Advanced › Liquid cooling |
| Boolean | linearizedLiq | false | = true, use linear relation between m_flow and dp for liquid cooling |
| Dynamics › Air cooling |
| Modelica.Fluid.Types.Dynamics | energyDynamicsAir | Modelica.Fluid.Types.Dynamics.DynamicFreeInitial | Type of energy balance for air-cooled component: dynamic (3 initialization options) or steady state |
| Modelica.Units.SI.Time | tauAir | 2 | Time constant of air outlet temperature at nominal flow |
| Initialization › Air cooling |
| Modelica.Units.SI.Temperature | TAir_start | 293.15 | Start value of air temperature |
Contents
| Name | Description |
|---|
 MediumLiq | Medium for liquid cooling loop |
| MediumAir | Medium for air cooling loop |
Revisions
-
July 14, 2026, by Michael Wetter:
First implementation.
